Natural History Museum Library
000163823
PHILOSOPHICAL
TRANSACTIONS
OP THE
ROYAL society
OR
LONDON.
FOR THE YEAR MDCCCLXV.
VOL. 155.
LONDON:
PRINTED BY TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET.
MDCCCLXV.
ADVERTISEMENT.
The Committee appointed by the Royal Society to direct the publication of the
Philosophical Transactions , take this opportunity to acquaint the Public, that it fully
appears, as well from the Council-books and Journals of the Society, as from repeated
declarations which have been made in several former Transactions , that the printing of
them was always, from time to time, the single act of the respective Secretaries till the
Forty-seventh Volume; the Society, as a Body, never interesting themselves any further
in their publication, than by occasionally recommending the revival of them to some of
their Secretaries, when, from the particular circumstances of their affairs, the Transactions
had happened for any length of time to be intermitted. And this seems principally to
have been done with a view to satisfy the Public, that their usual meetings were then
continued, for the improvement of knowledge, and benefit of mankind, the great ends
of their first institution by the Eoyal Charters, and which they have ever since steadily
pursued.
But the Society being of late years greatly enlarged, and their communications more
numerous, it was thought advisable that a Committee of their members should be
appointed, to reconsider the papers read before them, and select out of them such as
they should judge most proper for publication in the future Transactions; which was
accordingly done upon the 26th of March 1752. And the grounds of their choice are, and
will continue to be, the importance and singularity of the subjects, or the advantageous
manner of treating them ; without pretending to answer for the certainty of the facts,
or propriety of the reasonings, contained in the several papers so published, which must
still rest on the credit or judgement of their respective authors.
It is likewise necessary on this occasion to remark, that it is an established rule of
the Society, to which they will always adhere, never to give their opinion, as a Body,
upon any subject, either of Nature or Art, that comes before them. And therefore the
a 2
[ iv ]
thanks, which are frequently proposed from the Chair, to be given to the authors of
such papers as are read at their accustomed meetings, or to the persons through whose
hands they received them, are to be considered in no other light than as a matter of
civility, in return for the respect shown to the Society by those communications. The
like also is to be said with regard to the several projects, inventions, and curiosities of
various kinds, which are often exhibited to the Society ; the authors whereof, or those
who exhibit them, frequently take the liberty to report and even to certify in the public
newspapers, that they have met with the highest applause and approbation. And
therefore it is hoped that no regard will hereafter be paid to such reports and public
notices ; which in some instances have been too lightly credited, to the dishonour of the
Society.
The Meteorological Journal hitherto kept by the Assistant Secretary at the Apart-
ments of the Eoyal Society, by order of the President and Council, and published in
the Philosophical Transactions, has been discontinued. The Government, on the recom-
mendation of the President and Council, has established at the Eoyal -Observatory at
Greenwich, under the superintendence of the Astronomer Eoyal, a Magnetical and
Meteorological Observatory, where observations are made on an extended scale, which
are regularly published. These, which correspond with the grand scheme of observations
now carrying out in different parts of the globe, supersede the necessity of a continuance
of the observations made at the Apartments of the Eoyal Society, which could not be
rendered so perfect as was desirable, on account of the imperfections of the locality and
the multiplied duties of the observer.
A List of Public Institutions and Individuals, entitled to receive a Copy of the Philosophical
Transactions of each year, on making application for the same directly or through their
respective agents, within five years of the date of publication.
Observatories.
Armagh.
Cape of Good Hope.
Dublin.
Edinburgh.
Greenwich.
Kew.
Liverpool.
Madras.
Oxford (Radcliffe).
Institutions.
Barbadoes Library and Museum.
Calcutta Asiatic Society.
Geological Museum.
Cambridge Philosophical Society.
Cape Town South African Library.
Dublin Royal Dublin Society.
Royal Irish Academy.
Edinburgh Royal Society.
London Admiralty Library.
Chemical Society.
College of Surgeons.
Entomological Society.
Geological Society.
Geological Survey of Great Britain.
Horticultural Society.
Institute of British Architects.
Institution of Civil Engineers.
Linnean Society.
London Institution.
Royal Asiatic Society.
Royal Astronomical Society.
Royal College of Physicians.
Royal Geographical Society.
Royal Institution of Great Britain.
Royal Medical and Chirurgical Society.
Royal Society of Literature.
Society of Antiquaries.
Society of Arts.
The Queen’s Libraiy.
The Treasury Library.
United Service Museum.
Zoological Society.
Halt a Public Library.
Manchester Literary and Philosophical Society.
Melbourne University Library.
Montreal McGill College.
Oxford Ashmolean Society.
Radcliffe Library.
Swansea Royal Institution.
Sydney University Library.
Woolwich Royal Artillery Library.
Belgium.
Brussels Academie Royale de Medecine.
Royal Academy of Sciences.
DenmarTc.
Copenhagen Royal Society of Sciences.
France.
Montpellier Academy of Sciences.
Eaculte de Medecine.
Paris Academy of Sciences.
Depot de la Marine.
Ecole des Mines.
Geographical Society.
Geological Society.
Jardin des Plantes.
Societe d’Encouragement pour l’lndustrie
Rationale.
Toulouse Academy of Sciences.
Germany.
Altona Observatory.
Berlin Royal Academy of Sciences.
Society of Experimental Philosophy.
Briinn Haturforschender Yerein.
Dresden Caesarean Acad, of naturalists.
Erankfort natural History Society.
Giessen University.
Gottingen University.
Hamburg naturwissenschaftlicher-Yerein.
Konigsberg Koniglichen Physikalisch Okonomischen
Gesellschaft.
Leipzig Royal Saxon Society of Sciences.
Mannheim ...... Observatory.
Munich Royal Academy of Sciences.
Prague Bohemian Society of Sciences.
Vienna Imperial Academy of Sciences.
Geologische Reiehsanstalt.
Wurzburg Physico-Medical Society.
A List of Public Institutions and Individuals, entitled to receive a Copy of the Philosophical
Transactions of each year, on making application for the same directly or through their
respective agents, within five years of the date of publication ( continued ).
Hungary.
Pesth Hungarian Academy of Sciences.
Italy.
Bologna Academy of Sciences.
Catanea Accademia Gioenia di Scienze Naturali.
Florence Royal Observatory.
Milan Institute of Sciences, Letters, and Arts.
Modena Italian Society of Sciences.
Naples Institute of Sciences.
Palermo Academy of Sciences and Letters.
Rome Academy de’ Nuovi Lincei.
Collegio Romano.
Turin Royal Academy of Sciences.
Venice Institute of Sciences, Letters, and Arts.
Java.
Batavia .......... Batavian Society of Sciences.
Netherlands.
Amsterdam ...... Royal Institute.
Haarlem ........ Dutch Society of Sciences.
Rotterdam ...... Batavian Society of Experimental
Philosophy.
Portugal.
Lisbon Royal Academy of Sciences.
Russia .
Kazan Imperial University.
Moscow Imperial Society of Naturalists.
Public Museum.
Pulkowa Observatory.
St. Petersburg .... Imperial Academy of Sciences.
Spain.
Cadiz Observatory.
Madrid Royal Academy of Sciences.
Sweden and Norway.
. Christiania Royal University.
Drontheim Royal Society of Sciences.
Gottenburg Kongl. Vetenskaps oeh Vitterhets
Samhalle.
Stockholm Royal Academy of Sciences.
Switzerland.
Bern Allg. Schweizerischen Gesellschaft.
Geneva Societe de Phys. et d’Hist. Naturelle.
Transylvania.
Klausenburg Society of the Transylvanian Museum.
United States.
Albany New York State Library.
Boston American Academy of Sciences.
Newhaven (Conn.) .The Editors of the American Journal.
Cambridge Harvard University.
Philadelphia Academy of Natural Sciences.
American Philosophical Society.
Washington ...... Smithsonian Institution.
Observatory.
Th Q fifty Foreign Members of the Royal Society.
A List of Public Institutions and Individuals, entitled to receive a Copy of the Astro-
nomical Observations (including Magnetism and Meteorology) made at the Royal
Observatory at Greenwich, on making application for the same directly or through
their respective agents, within two years of the date of publication.
Observatories.
Institutions.
Altona.
Aberdeen
Armagh.
Berlin
Berlin.
Bologna
Breslau.
Boston
Brussels.
Brunswick, U.S. . .
Cadiz.
Cambridge
Cambridge.
Cambridge, U.S. . .
Cape of Good Hope.
Dublin
Coimbra.
Edinburgh
Copenhagen.
Royal Society.
Dorpat.
Glasgow
Dublin.
Gottingen
Edinburgh.
Leyden
Helsingfors.
London
Konigsberg.
Royal Institution.
Madras.
Royal Society.
Mannheim.
The Queen’s Library.
Marseille.
Oxford
Milan.
Paris
Munich.
Board of Longitude.
Oxford.
Depot de la Marine.
Palermo.
Pesth
Paris.
Philadelphia
Seeberg.
St. Andrews
Tubingen.
St. Petersburg ....
Turin.
Stockholm
Vienna.
Upsal
Wilna.
Waterville, Maine (U.S.) . . College.
Individuals.
Lowndes’ Professor of Astronomy Cambridge.
Plumian Professor of Astronomy Cambridge.
President of the Eoyal Society London.
South, Sir James .
The Earl of Rosse .
A List of Observatories, Institutions and Individuals, entitled to receive a Copy of the
Magnetical and Meteorological Observations made at the Koyal Observatory, Greenwich.
Observatories.
Bombay
Lieut. P. W. Mitcheson.
Cambridge, United States . .
Prof. J. Lovering.
Christiania
C. Hansteen.
Gotha
P. A. Hansen.
Heidelberg
M. Tiedemann.
Kew
B. Stewart.
Kremsmiinster
P. A. Beslhuber.
Leipzig
Professor Mobius.
Lisbon
Senhor da Silveira.
Marburg
Professor Gerling.
Prague
K. Jelinek.
Stockholm
Professor H. Selander.
St. Petersburg
(Twelve copies for distri-
bution to the Bussian
Mag. and Met. Obs.)
Toronto
Professor Kingston.
Upsal
Washington
Professor Svanberg.
Institutions.
Bombay Geographical Society.
Bonn University.
Boston, U.S The Public Library (late
Bowditch).
Cambridge Philosophical Society.
Cherkow University.
Falmouth Boyal Cornwall Poly-
technic Society.
London House of Lords, Library.
House of Commons, Li-
brary.
King’s College.
Boyal Society.
University College, Li-
brary.
Paris Meteorological Society.
St. Bernard Convent. .
"Washington Smithsonian Institution.
Woolwich Office of Mag. and Met.
Publication.
Individuals.
Bache, Dr. A. D
Washington.
Buys Ballot, Dr
Utrecht.
Dove, Prof. H. W
Berlin.
Erman, Dr. Adolph
Berlin.
Fox, B. W., Esq
Falmouth.
Harris, Sir W. Snow
Plymouth.
Hoskins, Dr. S. E
Guernsey.
Kaemtz, Prof. L. F
Dorpat.
Kreil, Prof. K
Vienna.
Lloyd, Bev. Dr
Dublin.
Loomis, Prof. E.
Yale College, New-
haven (Conn.).
Phillips, Prof. John
Oxford.
Quetelet, A
Brussels.
Sabine, Major-General, B.A. . .
London.
Senhor da Souza
Coimbra.
Vernon, G. V., Esq
Manchester.
Wartmann, Prof. Elie
Geneva.
Younghusband, Col., B.A
Woolwich.
Adjudication of the Medals of the Royal Society for the year 1865 by
the President and Council.
The Copley Medal to Mons. Michel Chasles, For. Memb. R.S., for his Historical
and Original researches in Pure Geometry.
A Royal Medal to Joseph Prestwich, Esq., F.R.S., for his numerous and valuable
Contributions to Geological Science, and more especially for his Papers published in
the Philosophical Transactions, on the general question of the Excavation of River-
valleys, and on the Superficial Deposits in France and England in which the Works of
Man are associated with the remains of Extinct Animals.
A Royal Medal to Archibald Smith, Esq., F.R.S., for his Papers in the Philosophical
Transactions, and elsewhere, on the Magnetism of Ships.
Professor H. E. Roscoe’s Paper, entitled “ On a Method of Meteorological Regis-
tration of the Chemical Action of Total Daylight,” was appointed as the Bakerian
Lecture.
The Croonian Lecture was delivered by Professor Lionel Smith Beale, F.R.S. : it
was entitled “ On the Ultimate Nerve-fibres distributed to Muscle and some other
tissues, with Observations upon the Structure and probable Mode of Action of a Nervous
Mechanism.”
CONTENTS
OF VOL. 155.
I. On the Spectra of Ignited Gases and Vapours , with especial regard to the different
Spectra of the same elementary gaseous substance. By Dr. J. Plucker, of Bonn ,
For. Mernb. B.S. , and Dr. J. W. Hittorf, of Munster page 1
II. On the Osteology of the genus Glyptodon. By Thomas H. Huxley, F.B.S. . . 31
III. Investigations of the Specific Heat of Solid Bodies. By Hermann Kopp. Com-
municated by T. Graham, Esq., F.B.S. 71
IV. On the Composition of Sea-water in the different parts of the Ocean. By Georg
Forchhammer, Professor at the University , and Director of the Polytechnic Insti-
tution at Copenhagen. Communicated by the President 203
V. On the Magnetic Character of the Armour-plated Ships of the Boyal Navy, and on
the Effect on the Compass of particular arrangements of Iron in a Ship. By
Frederick: John Evans, Esq., Staff Commander B.N., F.B.S., Superintendent of
the Compass Department of Her Majesty's Navy; and Archibald Smith, Esq.,
M.A., F.B.S., late Fellow of Trinity College, Cambridge, Corresponding Member
of the Scientific Committee of the Imperial Bussian Navy 263
VI. On some Foraminifera from the North Atlantic and Arctic Oceans, including Davis
Straits and Baffin's Bay. By W. Kitchen Parker, F.Z.S., and Professor T.
Rupert Jones, F.G.S. Communicated by Professor Huxley, F.B.S. . . 325
VII. New Observations upon the Minute Anatomy of the Papillae of the Frog's Tongue.
By Lionel S. Beale, M.B., F.B.S., Fellow of the Boyal College of Physicians,
Professor of Physiology and of General and Morbid Anatomy in King's College,
London ; Physician to King's College Hospital, &c 443
VIII. A Dynamical Theory of the Electromagnetic Field. By J. Clerk Maxwell,
F.B.S 459
[ Vi ]
IX. On the Embryogeny of Antedon rosaceus, Linck (Comatula rosacea of Lamarck).
By Professor Wyville Thomson, LL.D., F.B.S. E., M.B.I.A., F.G.S., &c. Com-
municated by Thomas Henry Huxley, F.B.S page 513
X. On the Sextactic Points of a Plane Curve. By A. Cayley, F.B.S 545
XI. A Description of some Fossil Plants , showing Structure , found in the Lower Coal-
seams of Lancashire and Yorkshire. By E. W. Binney, F.B.S. . . . . 579
XII. The Bakerian Lecture. — On a Method of Meteorological Registration of the
Chemical Action of Total Daylight. By Henry Enfield Roscoe, B.A., F.B.S.,
Professor of Chemistry in Owens College , Manchester 605
XIII. On the Commissures of the Cerebral Hemispheres of the Marsupialia and Mono-
tremata as compared with those of the Placental Mammals. By William Henry
Flower, F.B.S., F.B.C.S. , Conservator of the Museum of the Royal College of
Surgeons of England 633
XIV. On the Sextactic Points of a Plane Curve. By William Spottiswoode, M.A.,
F.B.S., &c 653
XV. On the Marsupial Pouches, Mammary Glands, and Mammary Foetus of the Echidna
Hystrix. By Professor Owen, F.B.S., &c 671
XVI. On the Influence of Physical and Chemical Agents upon Blood ; with special refer-
ence to the mutual action of the Blood and the Respiratory Gases. By George
Harley, M.D., Fellow of the Royal College of Physicians, Professor of Medical
Jurisprudence in University College, London. Communicated by Professor
Sharpey, M.D., Sec. B.S. 687
XVII. On a New Geometry of Space. By J. Plucker, of Bonn, For.Memb. B.S. 725
Index 793
Presents
Appendix.
[ i ]
LIST OF ILLUSTRATIONS.
Plates I. to III. — Drs. J. Plucker and J. W. Hittorf on the Spectra of Ignited Gases
and Vapours.
Plates IV. to IX. — Professor Huxley on the Osteology of the genus Glyptodon.
Plates X. & XI. — Staff-Commander Evans and Mr. A. Smith on the Magnetic Cha-
racter of the Armour-plated Ships of the Royal Navy.
Plates XII. to XIX. — Mr. W. K. Parker and Professor T. R. Jones on some Forami-
nifera from the North Atlantic and Arctic Oceans.
Plate XX. — Professor Kopp on the Specific Heat of Solid Bodies.
Plates XXI. and XXII. — Professor Beale’s New Observations upon the Minute Anatomy
of the Papillae of the Frog’s Tongue.
Plates XXIII. to XXVII. — Professor W. Thomson on the Embryogeny of Antedon
rosaceus , Linck ( Comatula rosacea of Lamarck).
Plates XXVIII. & XXIX. — Professor Roscoe on a Method of Meteorological Regis-
tration of the Chemical Action of Total Daylight.
Plates XXX. to XXXV. — Mr. E. W. Binney on some Lower-coal-seam Fossil Plants.
Plates XXXVI. to XXXVIII. — Mr. W. H. Flower on the Cerebral Commissures of
the Marsupialia and Monotremata.
Plates XXXIX. to XLI. — Professor Owen on the Marsupial Pouches, Mammary
Glands, and Mammary Foetus of the Echidna Eystrix.
PHILOSOPHICAL TRANSACTIONS.
I. On the Spectra of Ignited Gases and Vapours, with especial regard to the different
Spectra of the same elementary gaseous substance. By Dr. J. Plucker, of Bonn,
For. Memb. B.S., and Dr. J. W. Hittorf, of Munster.
Received February 23, — Read March 3, 1864.
1. In order to obtain the spectra of all the elementary bodies, you may make use either
of flame or the electric current. For this purpose flame is preferable on account of its
easy management, and therefore was immediately introduced into the laboratory of the
chemist. But its use is rather limited, the metals of alkalies being nearly the only sub-
stances which, if introduced into flame, give spectra exhibiting well-defined bright lines.
In the case of the greater number of elementary substances the temperature of flame,
even if alimented by oxygen instead of air, is too low. Either these substances are
not reduced into vapour by means of flame, or, if reduced, the vapour does not reach the
temperature necessary to render it luminous in such a degree that by prismatic analysis
we obtain its characteristic rays. The electric current, the heating-power of which may
be indefinitely increased by increasing its intensity, is alone fitted to produce the pecu-
liar spectra of all elementary bodies.
2. In applying the electric current we may proceed in two ways. In one mode of
proceeding the substance to be examined by its spectrum is at the same time, by means
of the current, transformed into vapour and rendered luminous. In the other mode
the substance is either in the gaseous state, or, if not, has been converted into it by
means of a lamp, and the electric current ignites the substance in passing through.
3. The first way of proceeding is the least perfect, but we are obliged to recur to it
in the case of all such elementary bodies as neither by themselves nor combined with
other substances can be vaporized without altering the least-fusible glass. If the sub-
stance to be examined be a metal, the extremities of the conducting- wires are made of
it and placed at a short distance from one another. When the strong spark of a large
Leyden jar, charged by Ruhmkorff’s powerful induction-coil, is sent through the space
between the two extremities of the conducting-wires, minute particles of the metal,
mdccclxv. b
2
DES. J. PLUCKEE AND J. W. HITTOEF ON THE
starting off from them, are volatilized: even in the gaseous state they conduct the
electric current from point to point, and exhibit, while heated by it, the characteristic
spectral lines of the metal. In all experiments made in this way, either air or another
permanent gas occupied the space between the two extremities of the wires. The con-
sequence of this is, the interposed gas partly conducting the electric current on its way
through it, two spectra are obtained at the same time — the spectrum of the metal and
the spectrum of the interposed gaseous medium. This inconvenience is the greater, as
in most cases the number of bright lines constituting gas-spectra is a considerable one ;
it is least in the case of hydrogen, the spectrum of which, if appearing under these con-
ditions, becomes nearly a continuous one (59). If the substance submitted to experi-
ment be not a metal or charcoal, the extremities of the metallic wires are to be covered
with it. Then we get with the spectrum of the non-conducting substance at the same
time the spectrum of the metal covered by it.
4. The spectra are obtained the most beautifully and are the most suitable for exami-
nation in their minute details, if the substance be in the gaseous state before the electric
discharge is sent through it. The spectral tubes for enclosing gas, first proposed and
employed by one of us, were in most cases, with some modifications, adopted for our more
recent researches. Our tubes, as represented by the diagram (fig. 1), gene- ^
rally consist of a capillary middle part 30-40 millims. long, and T5-2 millims.
in diameter, forming a narrow channel, by which two larger spheres, with
platinum electrodes traversing the -glass, communicate with one another.
The small tube starting from one of the spheres serves to establish the com-
munication with the exhauster, to which it is either attached by means of a
cement (sealing-wax for instance), or soldered by the blowpipe. The ex-
hauster, made solely of glass, without any metal, is connected with an addi-
tional system of glass tubes and glass cocks, by means of which the spectral
tube is most easily filled with the gas to be examined. If the gas be a per-
manent one, the apparatus by which it is developed, and its accessory parts,
by which it is purified and dried, may, as well as the spectral tube, simulta-
neously and separately be evacuated. The gas arrives directly from the appa-
ratus into the tube, which, ad libitum , may be alternately filled and ex-
hausted again. Finally, the tension of the gas is regulated and measured
by means of a manometer in connexion with the exhauster.
5. In order to compare with one another the spectra corresponding to different
densities of the gas, or even to a mixture of different gases, the tube may be examined
by the spectroscope while attached to the exhauster. But generally the spectral tube
was blown off and hermetically sealed at the extremity of the narrow tube starting
from one of the spheres. This tube equally serves to attach the spectral tube before
the slit of the spectroscope.
6. If the substance submitted to examination were at the ordinary temperature in
the liquid or solid condition, the tube destined to receive it was made of a glass diffi-
SPECTRA OF IGNITED GASES AND VAPOURS.
3
cultly fusible, and bent as shown by the diagram (fig. 2). After having introduced into it
a small quantity of the substance, the last traces of air were expelled from the tube, which
was finally blown off. Put before the slit of the spectroscope, the enclosed substance
was, by means of a lamp, reduced into vapour and, if necessary, kept in the gaseous
state (fig. 3), and the density of the vapour regulated. The glass of our spectral tubes
of this description is fused with such difficulty, that these highly evacuated tubes, when
becoming red-hot by the lamp, are not altered by the pressure of the surrounding air.
Fig. 2. Fig. 3.
7. Before giving a general account of the results we have obtained, it seems necessary
to enter into some preliminary discussions regarding the admirable working of Geissler’s
exhauster, and the phenomena shown by our tubes when highly evacuated by it. The
essential part of Geissler’s exhauster is a large glass ball, containing ten to twenty
kilogrammes of mercury, which in its upper part communicates, by means of a doubly
perforated stopcock of glass, either with the free air, or with the spectral tube to be
evacuated. From the lower part of the ball, which is invariably fixed, descends a longer
tube of glass communicating at its lower extremity with a moveable similar tube, the
free end of which enters into a large open bottle. When this bottle with the moveable
tube is lifted up, the mercury within the apparatus entirely fills the ball, if commu-
nicating with the air. This communication having been interrupted, a Torricellian
vacuum is formed when the bottle descends. By establishing the communication with
the spectral tube, the gas within it will be dilated. After the ascent and descent of mer-
cury has thus been alternately produced often enough, no perceptible trace of air will
remain within the spectral tube.
8. A tube evacuated in this way does not permit the induction current of Ruhmkorff’s
smaller apparatus (which in air gives a spark of about 15 millims.) to pass through.
The current of his large apparatus forces a passage ; but the spectrum we obtain in this
case is very faint ; it shows no traces of the bands of nitrogen, but solely the lines of
hydrogen and the large fields of vaporized carbon (51). The hydrogen-lines take their
origin from hygroscopic water covering the interior surface of the spectral tube, the
carbon-bands probably from the minute traces of fatty matter hitherto employed in
b 2
4
DES. J. PLUCKEE AND J. W. HITTOEF ON THE
greasing the stopcocks. (The oxygen simultaneously obtained by decomposition is not
indicated.) The hydrogen-lines given by spectral tubes made of common glass are
more brilliant than those of tubes made of less fusible glass, the hygroscopic state of the
glass not being the same in both cases. Though within the interior of the exhauster
the air is in contact with the surface of concentrated English sulphuric acid, or, what is
preferable, with anhydrous phosphoric acid, we never succeeded in expelling the last traces
of hygroscopic water, not even by strongly heating the spectral tube during evacuation.
If, in the usual way, a Leyden jar be intercalated into the current of Ruhmkorff’s
large induction coil, we must conclude, from the powerful charge of the jar, as proved
by flashes of light, that within the spectral tube the tension of electricity, before it
effects its passage, is very high. In this case the electric light is more bright, and of a
fine colour like that of blue steel. When analyzed by the prism, it shows the spectral
lines of hydrogen and oxygen, mixed with other spectral lines, among which those of
sodium and silicium are the brightest. At the same time the interior surface of the
capillary part of the tube tarnishes. Hence we conclude that the decomposed glass
partly conducts the current.
By means of our tubes, therefore, the theoretical conclusions of Dr. Faraday, that
electricity being merely a peculiar condition of ponderable matter cannot exist without
it, and cannot move without being carried by it, are confirmed and supported in a
striking way*.
9. As soon as the tube encloses perceptible traces of air, the spectral lines resulting
from the ingredients of the glass entirely disappear. Though the temperature of the
gas be raised by the passing current to an immense height, nevertheless, on account of
its great tenuity and the short duration of the discharge, the gas is not able to heat the
surface of the glass sufficiently to volatilize it. In this case also no spectral lines owing
to particles starting from the platinum electrodes appear in the capillary part of the
tube. Those lines are to be seen only near the electrodes, namely, in the aureola
surrounding the negative pole.
10. The temperature of the particles of air seized by the weakest electric spark by
far surpasses the temperature of the hottest obtainable flame. For no flame whatever
shows the spectral lines of air, which are constantly seen in the spark. In order to raise
the temperature of the discharge of Ruhmkorff’s induction coil, you may either increase
the power of the inducing current, or diminish the duration of the induced one. The last
plan may be found preferable in most cases. The heat excited in a given conductor by
a current sent through it increases in the ratio of the square of intensity, but decreases in
the ratio of the duration of the current. Admitting, therefore, that the conductibility
is not altered by elevation of temperature, and that the quantity of induced electricity
remains the same, we conclude that the heating-power of the induced current is in the
inverse ratio of its duration. But the resistance opposed by gases to the passage of
* Mr. Gassiot has already obtained vacua so nearly perfect as to present an obstacle to electric conduction.
See Philosophical Transactions for 1859, p. 148.
SPECTRA OE IGNITED GASES AND VAPOURS.
5
electricity depends essentially upon their temperature. At the ordinary temperature it
is rather too great to be measured, but, according to hitherto unknown laws, it rapidly
decreases when the temperature rises beyond that of red heat. The law above men-
tioned is therefore not strictly applicable in the case of gaseous conduction.
11. Electricity can only be discharged through a given stratum of air, from one point
to another, after a certain electric tension takes place in these points. This tension
depends upon the chemical constitution of the gas, and, the gas being the same, it is
nearly in the ratio of its density and the distance of the two points. The quantity of
electricity required to produce that degree of tension which must precede the electric
discharge through our spectral tubes, enclosing gas of a given density, may be inde-
finitely increased by interposing a Leyden jar. The less the distance between the coat-
ings of the jar, and the larger their surface, the greater quantities of electricity will be
accumulated on them, ready for discharge at the moment when the electric tension of
the electrodes entering our tube reaches that intensity which alone allows the discharge
to take place. Thus the Leyden jar is the most proper and most easy means for short-
ening the duration of the discharge, and consequently increasing the temperature of
the gas.
In several cases, especially if a vapour like that of mercury be examined, which
isolates less, it will be found more convenient, instead of replacing the Leyden jar by a
larger one, to increase the charge of the same jar by intercalating into the circuit a spark
micrometer, by means of which you may add to the resistance within the spectral tube
the resistance of any stratum of air.
12. The leading idea by which one of us was guided when he first (1857) directed
his attention to spectral analysis, was to concentrate the light in Geissler’s tubes by con-
fining the electric current within a capillary channel *. The construction of our tubes
immediately follows from it. Accordingly we gave, for different purposes, a different
diameter to their capillary part. The length of this part is of very little influence if
the tubes are very highly exhausted ; we had to shorten our recent tubes, intended to
enclose gases and vapours of a greater density, rendered luminous by a powerful induc-
tion coil.
13. We employed in our researches the large spectral apparatus constructed by
M. Steiniieil. The refracting angle of one of the four flint prisms belonging to the
apparatus is 60°, the angle of the three others 45°. Generally we made use of only two
prisms (of 60° and 45°), and of a magnifying power of only 18.
It is well known that the slit of the apparatus, if illuminated by sodium-light (by the
flame of alcohol containing common salt), is seen double. According to the width of
the slit and the dispersive power of the prisms, the two well-defined images, having both
* Plucker : “ Spectra der elektrischen Licbtstromungen,” 30 Marz 1858, Poggendorff’s ‘ Annalen,’ vol. civ.;
“ Ueber die Spectra der verschiedenen Gase, wenn durch dieselben bei starker Verdiinnung die elektriscbe Ent-
ladung bindurchgebt,” 25 Aug. 1858, Ibid. vol. cv.; “ Ueber die Constitution der elektriscben Spectra von ver-
scbiedenen Gasen und Dampfen,” 5 Mai 1859, Ibid. vol. cvii.
6
DRS. J. PLUCKER AND J. W. HITTORF ON THE
the breadth of the slit as observed without the interposed prisms, are either superposed,
or touch one another, or are separated by a black space. In making use of the two
prisms, we generally regulated the aperture of the slit so that the two small sodium-
bands appeared separated by a black space having nearly the breadth of these bands.
In this case the angle at which the aperture of the slit is seen is equal to half the angu-
lar distance of the two middle lines of the bands, and therefore equal to half the angu-
lar distance of the two sodium-bands themselves after being reduced by narrowing the
slit to mathematical lines.
If the images touch each other, the aperture of the slit and the two sodium-lines are
seen at the same angle.
14. The first fact which we discovered in operating with our tubes, guided by the
above explained principles, was the following one : —
There is a certain number of elementary substances , which , when differently heated , fur-
nish two kinds of spectra of quite a different character , not having any line or any band
in common.
The fact is important, as well with regard to theoretical conceptions as to practical
applications — the more so as the passage from one kind of spectra to the other is by no
means a continuous one, but takes place abruptly. By regulating the temperature you
may repeat the two spectra in any succession ad libitum.
We will now treat more explicitly the case of Nitrogen , which first unfolded to us its
different spectra. These spectra, obtained in the easiest and most striking way, have
been examined by us in every point of view. The other cases of double spectra may
hereafter be spoken of in a more summary manner.
15. We examined nitrogen prepared in different ways, even in the state of greatest
purity ; but we found that, in order to get pure spectra of it, it was not necessary to
free the gas from all traces of air *. Therefore we may select the following prepara-
tion, imperfect as it is, in order to give an instance of constructing nitrogen-tubes.
Three absorbing apparatus were connected with one another and, by means of a stop-
cock, with the exhauster, the first two being filled with a solution of pyrogallic acid
in hydrate of potash, and the third with concentrated sulphuric acid. After having
evacuated the interior of the exhauster and the spectral tube connected with it, by care-
fully turning the stopcock air was very slowly admitted, leaving its oxygen and carbonic
acid to the first two, and its aqueous vapour to the third absorbing apparatus. Thus by
and by the exhauster, with the tube, was filled with nitrogen, the manometer always
indicating the tension of the gas. These operations being repeated several times by
alternately evacuating and introducing new nitrogen, finally, the tension of the gas
* Whatever may he, under certain conditions, the practical importance of prismatic analysis in detecting
certain substances converted into vapour, whatever may be its use in indicating traces of a single gas imper-
ceptible by other means, mixtures of permanent gases are not fitted to be examined by the prism. A gas, if
mixed in rather small proportion with another one, entirely escapes observation. The proportion necessary to
render it visible depends upon the nature of the gas as well as upon the temperature of ignition.
SPECTEA OE IGNITED GASES AND VAPOUES.
i
(measured by means of the manometer) being from 40 millims. to 80 millims., the spec-
tral tube was melted off and hermetically sealed.
16. When we send through our nitrogen-tube the direct discharge of Ruhmkorff’s
large induction coil, without making use of the Leyden jar, we observe a beautiful
richly coloured spectrum. This spectrum is not a continuous one, but divided into
bands, the character of which differs essentially at its two extremities ; its middle part
is in most cases less distinctly traced. Towards the more refracted part of the spectrum,
the bands, illuminated by the purest blue or violet light, present a channeled appear-
ance *. This effect is produced by a shading, the intensity of which decreases from the
more to the less refracted part of each band. On applying four prisms instead of two,
we perceive a small bright line, forming an interstice between two neighbouring chan-
nels, and the shading is, by the telescope of the spectral apparatus, resolved into dark
lines. The number of such dark lines of one of the brightest bands (of the eighth band,
we always count from the red to the violet) was found to be thirty-four, or nearly so.
Their mutual distance is nearly the same, but their darkness decreases towards the least-
refracted limit of each channeled band. Hence we concluded, the breadth of the band
having been measured, that the angular distance of two contiguous shading-lines was
nearly equal to the distance of the two sodium-lines. The breadth of the channeled
bands varies, but the character of all is absolutely the same ; only if foreign bright
lines like those of hydrogen are simultaneously seen, it becomes slightly disturbed.
We may distinguish seventeen bands of this description ; the first three are smaller
ones, the fourth is traversed by H/3, the eleventh by Hyf. At the violet extremity the
light is very faint.
17. The bands of the less refracted part of the spectrum are all of nearly the same
breadth, but smaller than those just described, and of quite a different appearance.
Making use of only a single prism, and of a small magnifying power, we count eighteen
such bands, starting from the extreme red and extending to the greenish yellow,
where they are bounded by a dark space. H a falls within the fourth, and the double
sodium-line (Na) within the fourteenth of these bands. Under favourable circum-
stances, both extremities of the spectrum being equally developed, these bands extend
to the channeled part, their number rising to thirty-five. All have the same general
character, but not the same brightness. From the extreme red the intensity of light
* Under favourable conditions such a band appears furrowed semicircularly ; but psychological effects of this
description may be quite different : partly by our own will, partly by exterior circumstances, the bands may be
seen convex as well as concave. Even the engraving of the bands (Plate I.) shows it. Let it be illuminated by
daylight through a window, you will see the bands concave if their more refracted and shaded part be directed
towards the window ; if in the opposite direction, the bands will appear convex. The shade passes from one
side to the other if really concave and convex bands are replaced by one another ; so it does if the illuminating
light pass to the opposite side. Accordingly, the stereoscopic appearance depending upon the direction from
which the light comes, the mind passes judgment on it unconsciously.
t "We denote by Ha, H/3, and Hy the three bright lines of the spectrum of hydrogen (the red, the bluish
green, and the violet one). See 57.
8
DRS. J. PLUCKEE AND J. W. HITTORF ON THE
increases to the eighth band ; over the ninth, tenth, and eleventh, especially over the
two last, a shadow is spread, which gives to the red a rather brownish tint. The next
seven bands are of a fine orange and yellow colour. The nineteenth and twentieth bands
are very dark, the twenty-first is less dark. The following bands have a green colour,
varying in brightness. The darkest are the twenty-eighth and twenty-ninth, succeeding
the lightest ones.
The cause producing these bands and their shading by dark transverse lines is
evidently not the same as that which produces the shadow overspreading some of
them. This may be concluded, for instance, from the fact that the shadow which
darkens the nineteenth and twentieth bands, without entirely destroying their limits,
spreads at the same time over the neighbouring third part of the preceding eighteenth
band.
18. When the light sent out from the incandescent nitrogen within the capillary
tube is dispersed by means of four prisms, the shading of the less refracted bands also
is resolved into dark narrow lines ; but these lines are smaller than the similar lines of
the more refracted bands, and their distribution quite different. If the dispersion
increase, in each band we at first perceive a new dark limit ; but the design becoming
gradually more defined, we observe in each band extremely delicate bright lines
bounded by a shadow or by dark lines.
By closer examination of a band we distinguish first a least-refracted small part,
occupying about the seventh part of the whole, formed by two bright lines including
a somewhat larger dark space. The first of these two bright lines touches the dark
extremity of the preceding band ; the second is bounded by a subtle dark line, to
which succeeds a third bright line, smaller than the two first. A fourth bright line
divides the whole band into two parts, one less refracted, comprising the small one just
described, the other more refracted and larger — the breadth of the two parts being about
in the ratio of 4 : 5. Starting from the bright middle line, a feeble shading is produced
by a number of most subtle dark lines, the darkness of which decreases towards the
least-refracted part. Similar but darker lines produce the stronger shading of the
larger more refracted part, decreasing in the same direction from the extremity of the
whole band towards its bright middle line. The stereoscopic effect produced by the
shading of the bands is represented by the diagram (Plate I.).
The configuration of all the bright orange and yellow bands is exactly the same ; it
is rather obscured in the case of the preceding bands by the shadow spreading over
them, but becomes the same again in the bright red ones. Even in the dark bands 19
to 21, traces of the design are to be seen. The appearance of the green bands, though
the general character be the same, slightly differs ; the shading in the middle part of
them being increased, they rather seem to be divided into two.
The accordance of these bands, even to the minute detail of their configuration, is a
fact worthy of attention.
19. The character of the two systems of bands on the extremities of the spectrum is
SPECTEA OE IGNITED GASES AND YAPOUES.
9
entirely stereotype ; all apparent changes result from the different intensity of light.
The middle part of the spectrum, on the contrary, may much differ from that which we
have described ; you may even say that this part varies more or less essentially on
replacing one spectral tube enclosing nitrogen by any other. Sometimes the traces of
the less refracted bands are seen far beyond H/3, spreading over the channeled part of
the spectrum ; in other cases the channeled appearance goes in the opposite direction
as far as the sodium-line, disturbing the character of the bands.
20. Now, instead of the direct discharge of Ruiimkorff’s large induction coil, let us
send through the very same spectral tubes the discharge of the interposed Leyden jar.
The spectrum then obtained (Plate II.) has not the least resemblance to the former one.
The variously shaded bands which we have hitherto described are replaced by brilliant
lines on a more or less dark ground. Neither the distribution of these new lines nor
their relative brightness gives any indication whatever of a law. Nevertheless the place
occupied by each of them remains under all circumstances invariably the same. If
exactly determined, not only does each line undoubtedly announce the gas within the
tube, but the gas may even, without measuring, be recognized at first sight by charac-
teristic groups into which the lines are collected.
21. The new spectrum of nitrogen extends towards the red slightly beyond the
hydrogen-line Ha, which if the gas be not dried with care will be seen simultaneously,
enclosed by two red nitrogen-lines, the less refracted of which is twice as distant as the
more refracted. There are in the spectrum five groups of brilliant lines especially
remarkable. The orange group, slightly less refracted than Na, is formed by four lines,
the second of which is the brightest ; the third, not quite so bright, is closely followed
by the fourth, which is very faint. The second (yellow) group contains seven lines,
among which the fifth is brightest. The third (light-green) and the fourth (dark-green)
group contain each nine lines. The third and sixth lines of the light-green group and
the sixth and seventh (both near to each other) of the dark-green group are brightest.
The fifth (light-blue) group (the distance of its middle part from H/3 and Hy is about
in the ratio of 3 : 4) is formed by six lines, the second of which is the brightest, the first
slightly less bright ; the last four lines, nearly equally distant from each other, are
slightly less bright again. Two groups, of three fainter lines each, fall between the two
green groups and between the dark-green and the blue. We may mention also two
bright single lines, placed out of the groups — a green line preceded by an expanded
one, and a light-violet line followed at a short distance by a bright band. Besides,
there are in the spectrum more or less faint bands or expanded lines extending beyond
Hy nearly as far as the distance between this line and H/3, i. e. about to Fraunhofer’s
line H.
22. We may denote the orange, yellow, light-green, dark-green, and blue groups by
I, ii, hi, iv, and v, and the single lines of them by the arabic numbers, the place
they occupy in each group being reckoned from the less to the more refracted. Thus
by adding the chemical symbol of the gas we get a general method of denomination,
mdccclxv. c
10
DBS. J. PLUCKER AND J. W. HITTORP ON THE
according to which N n 5, N iv 6, N iv 7, and N v 2, for instance, indicate the brightest
lines of the groups of the nitrogen-spectrum.
23. Not only is the general character of the two kinds of spectra we obtained when
nitrogen was heated in our tubes, either by the direct discharge or by the discharge of
the interposed Leyden jar, quite different, but the difference is even so great that the
bright lines of one of the spectra do not in the least fall within the brighter part of the
bands constituting the other. Thus, for instance, the bright yellow line (N ii 5) falls
within the nineteenth band, the darkest of all the bands constituting the less refracted
part of the spectrum ; the bright blue line (N v 2) falls into the darker part of one of
the channeled spaces. Accordingly it appears by no means probable that by increasing
the temperature the shaded bands of one spectrum may be transformed gradually into
the bright lines of the other ; nevertheless it would be desirable to prove by experiment
that the passage from one spectrum to another is a discontinuous and abrupt one.
24. For a given nitrogen-tube which without the Leyden jar gives the spectrum of
bands, and by means of the commonly used jar the spectrum of bright lines, you may
easily select a jar of smaller covering, which, if intercalated, exhibits the curious phe-
nomenon of two rival spectra disputing existence with each other. Sometimes one of
the spectra, sometimes the other appears ; and for moments both are seen simultaneously.
Especially the brighter lines of the second spectrum abruptly appear in the blue and
violet channeled spaces of the first, and, according to the fluctuation of the induced
current, either suddenly disappear again or subsist for some time, and constitute with
the added fainter lines the second spectrum.
We obtain in an easier and a continuous way both spectra simultaneously by making
use of a small Leyden jar, and increasing its charge by an intercalated stratum of air
the thickness of which increases till the bright lines appear within the bands of the
primitive spectrum.
25. By these and other experiments it is evidently proved that ignited nitrogen shows
two quite distinct spectra. Each bright line of one of these spectra, each of the most
subtle lines into which, by means of the telescope, the bands of the other are resolved,
finally depends upon the molecular condition of the ignited gas, and the corresponding
modification of the vibrating ether within it. Certainly, in the present state of science,
we have not the least indication of the connexion of the molecular constitution of the
gas with the kind of light emitted by it ; but we may assert with confidence that, if one
spectrum of a given gas be replaced by quite a different one, there must be an analogous
change of the constitution of the ether, indicating a new arrangement of the gaseous
molecules. Consequently we must admit either a chemical decomposition or an allo-
tropic state of the gas. Conclusions derived from the whole series of our researches
led us finally to reject the first alternative and to adopt the other.
26. The same spectral tube exhibits, in any succession whatever, as often as you like,
each of the two spectra. You may show it in the most striking way by effecting the
intercalation of the Leyden jar by means of a copper wire immersed in mercury. As
SPECTEA OE IGNITED GASES AND VAPOURS.
11
often as the wire is taken out of the mercury we shall have the spectrum of bands ; as
soon as the communication is restored, the spectrum of bright lines. Hence we con-
clude that the change of the molecular condition of nitrogen which takes place if the
gas be heated beyond a certain temperature by a stronger current, does not permanently
alter its chemical and physical properties, but that the gas, if cooled below the same
limit of temperature, returns again to its former condition.
27. The essentially different character of the two extremities of the first spectrum of
nitrogen, as described (16-19), and the indistinctness of its middle part, suggested to us
the idea that, in reality, the observed spectrum might originate from the superposition
of two single spectra. Accordingly one of these single spectra, the more refracted part
of which is best developed, must be formed by channeled spaces ; the other one, the less
refracted part of which is best developed, must be a spectrum of shaded bands. In
different cases, either the one or the other of the spectra may be predominant.
In order to confirm our conjecture it was necessary to get the two spectra separated.
28. The discharge of Ruhmkorff’s coil through a spectral tube is changed the less
by introducing the Leyden jar, the weaker is the resistance opposed to it by the tube.
Accordingly the two different degrees of temperature to which the gas rises by the
discharge when, the coil remaining the same, we either make use of the jar or not,
may be regulated in such a way as to approach one another more and more. Let the
tension of the gas of about 10 millims. remain the same, the temperature produced by
the discharge will be diminished by increasing the interior diameter of the capillary
part of the spectral tube. Thus we succeeded in constructing a tube which, when the
direct discharge was sent through it, became incandescent with the most brilliant gold-
coloured light, which might easily be confounded with the light of highly ignited vapours
of sodium ; but with the intercalated jar, the light of the incandescent gas within the
same tube had a fine bluish-violet colour. The yellow light, when analyzed by the
prism, gave a beautiful spectrum of shaded bands, extending with decreasing intensity
to the blue, the channeled spaces being scarcely perceptible. The bluish light, when
examined, was resolved by the prism into channeled spaces extending towards the red,
while the former bands almost entirely disappeared. We may transform each colour
and its corresponding spectrum into the other ad libitum.
Hence it follows that there is another allotropy of nitrogen, which, like the former, is
not a stable and permanent one, but depends only upon temperature. The modification
in which nitrogen becomes yellow corresponds to the lower, the modification in which it
becomes blue to the higher temperature.
29. When we send the direct discharge of Ruhmkorff’s coil through one of Geissler’s
wider tubes enclosing very rarefied nitrogen or air (the oxygen of air becomes not visible
here), we see the negative pole surrounded by blue light, the light at the positive pole
being reddish yellow. In such of Geissler’s tubes as are especially calculated to show
how the light starting in all directions from the different points of the negative elec-
trode is by the action of an electro-magnet concentrated along the magnetic curves
c 2
12
DBS. J. PLUCKER AND J. W. HITTORF ON THE
passing through these points, the blue light is most beautiful. It belongs generally to
the nitrogen alone, which, on account of the greater resistance at the negative electrode
opposed to the discharge, reaches a higher intensity of heat there than at the positive pole.
When analyzed by the prism, the blue light gives the spectrum of channeled spaces, with
traces only of the less refracted bands. The reddish-yellow light of the positive pole is
more faint, and therefore not so easy to be submitted to spectral analysis.
30. When Ruhmkorff’s large induction coil is discharged in common air between
two points the distance of which does not exceed a few centimetres, we obtain, as is well
knoAvn, a brilliant spark surrounded by an aureola, the colour of which is partly bluish
violet, partly reddish yellow. In order to separate these colours more distinctly from
each other, the aureola, moved by the slightest breath, may be extended into a large
surface by blowing it sideways. But the separation may be best made when the dis-
charge takes place between the two poles of an electro-magnet in the equatorial direc-
tion. While the straight spark is not acted upon by the electro-magnet to any sensible
degree, the aureola is expanded into a fine surface, bounded by the spark starting from
one to the other extremity of the electrodes, and by a semicircle passing through these
extremities. At a certain rarefaction of air this surface appeared most beautifully
bounded by a semicircular golden-coloured band, and divided by a similar band into two
parts*. We may explain now in a satisfactory way the appearance, hitherto mysterious,
of the golden light. Both the yellow and the blue light are owing to the nitrogen of the
air, reduced by the heat of the current into the two allotropic states which exhibit the
spectra of channeled spaces and of bands. The brilliant white light of the spark partly
belongs to the oxygen, partly to the nitrogen of the air, both highly ignited, the nitrogen
being in that allotropic state in which it exhibits the spectrum of bright lines.
31. In order to complete the history of the spectrum of nitrogen we add two remarks.
First, by intercalating a Leyden jar and, in order to weaken the current, at the same
time a stratum of water or a wet thread, we may also reduce the spectrum of bright
lines to the spectrum of bands. Secondly, by increasing the density of the gas, or, if the
gas be less dense, by intercalating at the same time a large jar and a stratum of air, the
bright lines of the spectrum, at the highest obtainable temperature, will expand. Out
of a great number of observations made in this direction we shall describe only one.
32. A short spectral tube enclosing nitrogen of a tension of about 250 millims.
refused passage to the discharge of Ruhmkorff’s large induction coil, when three of
Grove’s elements were made use of and the jar intercalated. Without the jar the
discharge passed through and produced a bright but rather undefined spectrum of
bands. When the current continued to pass, the indistinctness of the spectrum in-
creased, and after short intervals brilliant coloured lines appeared and disappeared
again, like lightning-flashes. These lines, occupying always the same place, belonged
to the second spectrum of nitrogen, the brightest yellow and green lines of which
* Pll'cker, “TTeber die Einwirkung desMagnetes auf die elektrische Entladung,” Poggendohff's ‘Annalen,’
vol. cxiii. p. 267.
SPECTRA OF IGNITED GASES AND VAPOTJRS.
13
(N ii 5, N iv 6, N jv 7) were specially observed. When we made use of twelve of Grove’s
elements ranged into three sets of four combined ones, the current even passed after
we interposed the Jar, and we got a most dazzling second spectrum of the gas. The
bright lines of this spectrum, rising from a ground itself brighter than it usually is,
ceased at an increased brilliancy to be well defined. The two brilliant green lines both
expanded, and were united into a single broad line ; the double yellow lines, though
expanded, yet remained double. The spectrum was progressing towards a continuous one .
33. In recapitulating, we get the following results: —
Nitrogen in the state of greatest rarefaction, such as may be obtained by Geissler’s
exhauster, like other gases does not allow the induction current to pass through. But
when its tension is only a small fraction of a millimetre, the current begins to pass and
renders the gas luminous. Below a certain limit of temperature ignited nitrogen sends
out a golden-coloured light, giving the spectrum of bands. Above this limit the colour
of the light is replaced by a bluish violet, the spectrum of channeled spaces replacing
simultaneously the spectrum of bands. When, by means of the intercalated jar for
instance, the temperature rises to a second higher limit, the light of the gas, becoming
white and most brilliant, gives, if analyzed by the prism, a spectrum of quite a different
description : bright lines of different intensity, with the colour indicated by the place
they occupy, rise from a dark ground. By increasing the power of the discharge these
lines become more brilliant, but the brilliancy does not increase in the same ratio for
them all. New bright lines appear, which formerly, on account of their extreme faint-
ness, were not visible ; but the number of such lines is not unlimited. By increasing
the heat of the ignited nitrogen to the last extremity, the lines, especially the brighter
ones, gradually expand, approaching thus to a continuous spectrum.
34. Those spectra which are composed of larger bands showing various appearances
according to their being differently shaded by subtle dark lines , we generally call spectra
of the first order. In the same spectrum the character of the bands is to a certain extent
the same, the breadth of the bands varies in a more or less regular way. On the con-
trary, those spectra in which brilliant coloured lines rise from a more or less dark ground,
we call spectra of the second order.
Ignited nitrogen therefore exhibits, if its temperature increase, successively two
spectra of the first and one of the second order.
35. In the case of sulphur, which we may select as another instance, there are two
different spectra, one of the first and one of the second order.
In common air the flame of sulphur gives a continuous spectrum ; if fed with oxygen
we get a spectrum of the first order, but it is faint and its bands are not well defined.
In order to get the sulphur-spectrum most perfect, we must recur to our spectral tubes.
A doubly bent short tube (6), into which we introduced a small quantity of sulphur, was
evacuated by means of Geissler’s exhauster, and while attached to it heated by a lamp,
in order to expel as much as possible the moisture it contained. Finally, the mano-
meter showing no more tension of the remaining gas, the tube was hermetically sealed
14
DES. J. PLtJCKEE ANT) J. W. HITTOEF ON THE
by a blowpipe. The direct charge of Ruhmkorff’s large induction coil sent through it,
generally indicates by their spectra traces of remaining foreign substances (8). But
when the tube was heated by a small alcohol-lamp, at a certain moment a fine sulphur-
spectrum of the first order appeared, undisturbed by any former spectrum. The beauty
of the spectrum increased when we continued to heat moderately.
36. We counted thirty-seven well-defined bands, extending nearly from Ha to Hy.
Seven of these bands, the first of which was of a dark-red colour and visible only under
favourable circumstances, preceded the sodium-line, eighteen fell between this line and
H/3, and eleven between H/3 and Hy, the last of which being broader, appears some-
times divided into two. After a last band, traversed by Hy, a larger and strongly
shaded space extended towards the extreme violet. The breadth of the bands
increased from the less to the more refracted part of the spectrum. In each band,
contrary to what takes place in the case of nitrogen, namely, with regard to its chan-
neled spectrum, the shading produced by fine dark lines decreases from the less to the
more refracted extremity. The darkest part of the shadow is bounded by a small sepa-
rate band of a varied appearance, generally formed by two small bright lines including
a somewhat larger dark one. By these small bands the purely channeled character of
the spectrum is disturbed.
37. If, while the discharge is passing, we continue to heat the tube by a lamp, the
brightness of the spectrum always increases ; but if we approached to a certain degree of
temperature, in different parts of the spectrum we have described, bright-coloured lines
belonging to the sulphur-spectrum of the second order appeared and disappeared again
according to the fluctuating heat, till at last the second of the two rival spectra remained
undisturbed. The colour of the light was changed. In cooling again after the lamp
was taken off, the light within the tube changed its colour again, while the spectrum of
the second order was replaced by the spectrum of the first order.
There is a certain elevation of temperature at which the increased density of the
vapour does not permit the discharge to pass ; the light within the tube is extinguished,
but abruptly reappears after cooling.
38. Well-defined bright lines, constituting a fine sulphur-spectrum of the second
order, are obtained if moderate discharges of Rhumkoeff’s large induction coil are sent
through the tube, the tube being slightly heated by means of an alcohol-lamp, and a
small Leyden jar being intercalated. At first the spectrum extends only from about the
sodium-line to H/3. One observes chiefly a characteristic group of sixteen lines, followed
at some distance by two separate lines. The spectrum once developed persists even after
taking off the lamp. When we continue to heat, the brightness of the group increases
and its lines begin to expand, while at the same time the hitherto black ground is
coloured. The brilliancy may be increased to such an extent as to be unbearable to
the eye. Beyond the sodium-line, towards the red extremity, new distinct lines appear,
among which we particularly distinguish a triple line, remarkable as well for its fine
red colour as for its distinctness, and nearer to Ha a second such triple line, at first well
SPECTEA OF IGNITED GASES AND VAPOUES.
15
defined but soon merging into a single one. Like the less refracted part of the spec-
trum, the most refracted part is developed only at a higher ignition of the vapour of
the sulphur. At its violet extremity (we do not give here a full description of the
middle part) we observe at the same distance from one another five well-defined fainter
bright lines. Then follows, after an expanded violet band, a group of four bright lines,
the second of which is accompanied by a more refracted, the fourth by a less refracted
faint line. The fourth line especially is distinct to a degree seldom observed at so high
a refraction and so great a power of the discharge. After two bands of faint light,
there is seen at the end of the spectrum a group of four slightly expanded bright lines,
preceded by an expanded violet band.
39. Like sulphur, selenium has two spectra — one of the first, another of the second
order.
40. Ignited carbon, even in a state of greatest division, gives a continuous spectrum.
41. We select, among the various compound gases which, if decomposed in flame, give
the spectrum of carbon, in the first place cyanogen. The gas was procured by heating
cyanide of mercury introduced into a retort of glass by means of a lamp. The flame of
it may be fed either with oxygen or with air.
When a jet of cyanogen mixed with oxygen is kindled, in the interior part of the flame
a most brilliant cone of a whitish-violet light is seen, the limit between the ignited and
the cold part of the jet. This cone exhibiting the spectrum of vapour of carbon
best developed, we conclude that the cyanogen must be decomposed into carbon and
nitrogen, the carbon being in the gaseous condition a moment before its combination
with oxygen takes place*.
42. In order to prevent explosion of the mixture of cyanogen and oxygen, it is pre-
ferable that the jets of the two gases meet from opposite sides before the slit of the spec-
tral apparatus, forming there, if kindled, a brilliant, flat, vertical surface. The jet of
cyanogen might be obtained directly from the retort, by the heating of tvhich it may be
regulated. Thus we get, all being properly arranged, a splendid and richly coloured
spectrum. Especially we distinguish eight groups of bright lines , which, being all of
the same general character, indicate at first sight the existence of vapour of carbon. We
shall denote these groups, starting from the less refracted and proceeding to the more
refracted ones, by a, b, c, d, e, f, g , h. The group a is formed by five, b by six, c by
four, d by five, e by seven, f by three, g by seven, and h by three bright lines. But these
lines, of a measurable breadth and a quite different appearance, are not to be confounded
with the bright lines which, in the case of nitrogen and sulphur, for instance, constitute
spectra of the second order. In each group the first line is the brightest ; the following,
which are nearer to one another, decrease in intensity, and under less favourable circum-
stances the last ones are not seen. Hence the groups, according to an expression of
Mr. Attfield, have the appearance of a portico. The red group (a) is not always seen
distinctly (less distinctly in the present case than in the case of other gaseous com-
* Mr. Attfield has the merit of haying first stated that spectra hitherto attributed to compound gaseous
substances, are to he referred to the vapour of carbon itself (Philosophical Transactions for 1862, p. 221).
16
DES. J. PLtJCKEE AND J. W. HITTOEF ON THE
pounds of carbon) ; the group f is very faint, the group g beautifully violet, h rather
ultra-violet.
43. The whole spectrum, except its red extremity, is divided into large shaded fields.
The shadow increases from the less to the more refracted part of each field ; from its
Drighter less refracted part arise the bright lines of one group, the first of these lines
towards the darkest extremity of the preceding field. As well as in the former cases of
nitrogen and sulphur, the shadow is produced by dark transversal lines on a coloured
ground. But here the distance of the shading-lines from each other varies even in the
same field. Towards the bright, i. e. the less refracted extremity of each field, the
distance decreases, while at the same time the darkness and the breadth of the lines
is diminished. The space between two consecutive lines appeared to be greatest in the
field containing the group c, at a distance from d about twice as great as that from c.
There we counted, on making use of two prisms and applying a magnifying-power of
eighteen, the aperture of the slit being regulated in the ordinary way (13), nine shading-
lines, including eight nearly equal small bands, the total breadth of which corresponded
to five divisions of our arbitrary scale. Hence we computed the angular distance of
two consecutive dark lines which we observed to be about five-fourths of the distance of
the sodium-lines.
The dark shading-lines also appear within the bands bounded by the lines of the
brighter characteristic groups. The band between the second and the third bright line
of the yellow group b, the total breadth of which corresponds to four divisions of our
arbitrary scale, was divided by dark lines into twelve smaller bands of about equal
breadth. Accordingly the angular distance of two such consecutive lines is about two-
thirds the distance of the two sodium-lines. The dark lines within the neighbouring
band, bounded by the first and second bright line of the same group, were much nearer
to one another, and their number too great to be counted with certainty.
44. Between the groups f and g there is indicated a particular distribution of light
and shadow, which, being a faint copy of what takes place if olefiant gas be burned
instead of cyanogen, will be better understood after we have described the spectrum of
the new gas.
45. The least-refracted part of the spectrum, preceding the first line of the group a ,
essentially differs from the more refracted part already described. There are three fine
red bands contiguous to the first bright line of the group, extending nearly to Ha, and
beyond this hydrogen-line, after a dark space, two similar but not so well-defined bands.
The breadth of these bands is nearly the same, and all are shaded in a similar way.
Contrary to the distribution of shadow in the larger field, the shadow is strongest in the
less refracted part of each band ; in the most refracted part we observed two bright lines.
46. When the combustion of cyanogen took place in air, the bands we have just
described were best developed, and new similar ones added. They extended from beyond
Ha nearly to H/3. The breadth of these bands slightly increases towards the violet end
of the spectrum, their general description remaining the same. We especially counted
seven such bands, the first of which is traversed by the double sodium-line, and the last
SPECTEA OF IGNITED GASES AM) VAPOURS.
17
is bounded at the place formerly occupied by the second bright line of the character-
istic group c.
When the flame of cyanogen is fed by air, we observe under favourable circumstances
no traces of the groups a and b, the least-refracted bright line of the group c faintly
appears, d is scarcely indicated, but the groups e , f, g are fully developed, especially the
last one, of a fine violet colour.
46. In supplying the flame of cyanogen by air increasingly mixed with oxygen, we
distinctly see two spectra overlying one another. One of these spectra (the spectrum of
bands) giving way step by step to the other, the appearance is continually changed.
The red bands only remained undisturbed, they became even more distinct by the
increased intensity of the combustion. The adjacent group a is scarcely developed,
evidently on account of an imperfect extinction of the overlying bands.
The superposition of the two spectra introduces new details into the general configu-
ration of the resulting spectrum. Thus, for instance, at a certain intensity of combus-
tion the interval between the first and second bright line of the group b is divided by
four fine bright lines into five spaces, the breadth of which decreases towards the violet
part of the spectrum. Thus also in the large field containing the group c, the influ-
ence of the spectrum of bands is rendered sensible by a particular distribution of shadow.
47. Secondly, we submitted to a closer examination olefiant gas, H4 C4, when burned
either with oxygen or with air. We operated as we did in the former case of cyanogen ;
only the gas, prepared by heating a mixture of alcohol and sulphuric acid, was previ-
ously introduced into a gasometer.
The luminous cone which exhibits the spectrum of vapour of carbon is of a fine blue
colour, especially if the flame is fed by oxygen.
48. In the spectrum thus obtained the characteristic groups a, b, c, and d appeared
on a shaded ground. All these groups, especially the red one a, scarcely seen in the
spectrum obtained by the combustion of cyanogen, are finely developed. The last line
of b and d is slightly expanded ; but there is no trace whatever either of the bands of
the spectrum of cyanogen, if burned in common air, or even of the groups e and g.
Instead of these groups there is quite a new configuration. Equally distant from the
place which the groups occupied in the former spectrum, a small well-defined black
band was seen, bounded on the more refracted side by a violet space, which, being of
great brilliancy where it touches the band, was shaded gradually till the spectrum, not
extending beyond the place of the group g , was extinguished. This violet space is tra-
versed by well-defined dark lines, equally distant from each other, but more apart than
the shading lines we described in former cases. The black band is bounded on its less
refracted side by a bright line, having the breadth of the lines of the characteristic
groups, which at a certain distance was preceded by a more diffused violet light, tra-
versed, like the brilliant one on the opposite side, by dark but less distinct lines. Here
also the faint group f appeared.
The distribution of light and shade producing the configuration just described i&
MDCCCLXV. d
18
DRS. J. PLtJCKER AND J. W. HITTORF ON THE
seen also, distinctly but faintly, in the spectrum we obtained by the combustion of
cyanogen with oxygen, where at the same time the groups e and g are beautifully
expressed (44).
49. Among the gases exhibiting the spectrum of vapour of carbon, when enclosed in
our spectral tubes and decomposed by the heat of the discharge of Ruhmkorff’s coil,
we first select oxide of carbon. In operating with this gas as we did with nitrogen,
we got, if the Leyden jar was intercalated, simultaneously the spectrum of vapour of
carbon and the spectrum of oxygen ; without the jar, the pure spectrum of vapour of
carbon. In the last case the heat of the discharge is high enough to ignite vapour of
carbon, but not sufficient to give the spectrum of oxygen. The single spectrum, as well
as the combined one, is obtained accordingly ad libitum ; whence we conclude that as
the successive discharges pass through the spectral tube, the gas is alternately decom-
posed and recomposed again.
50. We shall in a few words describe the spectrum obtained without the jar, at a ten-
sion of the gas, when observed by means of the manometer before the spectral tube was
sealed, of 32 millims.
Four characteristic groups only were seen, a, b , c, and d. When the current
first passed, the band a appeared completely ; after some time its two first lines only
remained, rising as isolated bright lines from a dark ground ; finally all the group dis-
appeared. The groups b, c, and d remained nearly unchanged ; there appeared only
two bright lines of c , the place corresponding to the two following ones being very
brilliant.
The whole spectrum was divided into large fields, similar to the fields we described
in the case of the flame of cyanogen fed with oxygen. But in this case each field is
bounded at its more refracted and shaded extremity by the first bright line of a charac-
teristic group ; the following lines, bordered by shading, rise from the lightest part of
the adjacent field. In the new instance the fields are not bounded in the same way.
After the group a has disappeared, there is a differently shaded dark space, extending to
the place of the third bright line of that group. In the remaining part of the spec-
trum we may distinguish seven shaded fields. The first goes a little beyond the first
bright line of the group 5, where it is bounded by a transversal line, dividing the band
formed by the first two lines of the group into a dark less refracted and a light more
refracted part. Accordingly the first bright line rises from the dark end of the first
field, the remaining lines from the light end of the second field. The second field does
not reach the first bright line of the following group c , this line being nearly equally
distant from the extremity of the field and the next line of the same group. The third
field goes slightly beyond Hp ; the fourth to the first line of the group d ; the fifth
nearly to the place occupied by the fifth line of the group e ; the sixth approaches the
place of the group/; and the seventh extends to the fourth line of the group g. The
fourth and sixth fields presented the appearance of pure channeled spaces, as described
in the case of nitrogen.
SPECTRA OF IGNITED GASES AND VAPOIJES.
19
51. If the heating-power of the discharge be too strong, spectral tubes enclosing
oxide of carbon at a higher tension showed only three large shaded fields, without
any traces of the characteristic groups. The first two of these fields are coincident with
the second and third of the former fields ; the third occupies the place of the fourth
and fifth former fields united into one. Here the shading of the three large fields
not being disturbed by any additional appearance, the transversal shading lines were
observed most distinctly even in making use of four prisms and employing a magni-
fying power of 36. In observing especially the light and less refracted part of the first
field close to its extremity, these lines, on account of their extreme subtleness, are
scarcely to be perceived ; when they begin to become well defined they are very near to
each other; but towards the more refracted part of the field their distance increases
simultaneously with their breadth, till, at some distance from the bright extremity, the
dark expanded lines are resolved into small shaded bands*.
52. Spectral tubes containing carbonic acid instead of oxide of carbon gave essen-
tially the same spectra. The increased quantity of oxygen of the decomposed gas may
be observed by means of the interposed jar. In such tubes there was no carbon depo-
sited, not even after a long passage of the discharge.
53. All compound gases enclosed in our spectral tubes are decomposed by the heat
produced by the discharge of Ruhmkorff’s large induction coil ; but instantly after the
discharge passes, the recomposition takes place. The recomposition is prevented only
by a sudden cooling of the elementary gases obtained by the decomposition. Thus, for
instance, spectral tubes enclosing cyanogen are scarcely fitted for observation, the inte-
rior surface of their capillary part being instantaneously blackened by the deposited
carbon. No carburetted hydrogen resists final decomposition by the passing current.
We add only a few observations, made by means of spectral tubes.
54. The spectrum of the light hydrocarbon gas, C2 H4, obtained without the Leyden
jar, at once showed the expanded bright lines of hydrogen and an imperfect spectrum
of vapour of carbon, especially the brightest lines of the characteristic groups b , c,
and d. By intercalating the jar, the hydrogen-spectrum, approaching to a continuous
one, became quite predominant.
Olefiant gas , C4 H4, of a primitive tension of about 70 millims., gave, without the jar,
a scarcely visible spectrum ; by intercalating the jar, the three hydrogen-lines Ha, H/3,
Hy appeared well defined, and the spectrum of vapour of carbon, with its groups a, b,
c , d , and its shaded large fields, well developed.
Methyl , C2H3, showed, without the jar, at once Ha, H/3, Hy, and the characteristic
groups e and g ; with the interposed jar these two groups disappeared, and were replaced
by the groups a, b, c, and d.
Acetylene, C4 H2, though according to Berthelot and Morren formed from its
* The same spectrum, but fainter, is obtained under quite different conditions. We have already noticed,
in the introductory remarks, that in a spectral tube evacuated to the last degree by Geissler’s exhauster,
vaporized carbon is indicated by its spectrum. The spectrum obtained is that described above (8).
D 2
20
DES. J. PLUCKEE AND J. W. HITTOEF ON THE
elements when Davy’s charcoal light is produced within an atmosphere of hydrogen,
when introduced into our tubes is nevertheless rapidly decomposed by the discharge,
and most incompletely recomposed after the discharge has passed. The inside of the
tubes is instantly blackened, and in the first moment only, along with the spectrum of
hydrogen, we perceive the groups of carbon-lines seen in the case of olefiant gas.
55. Finally, Ruhmkorff’s large induction coil was discharged between two electrodes
of carbon, surrounded by an atmosphere of hydrogen. The four groups a , b, c, and d
were obtained, constituting the spectrum of vaporized carbon.
56. In resuming, we are struck by the variety of appearances presented by ignited
vapour of carbon when submitted to spectral analysis under different conditions. But,
whatever may be this variety, it is impossible not to admit that all or nearly all of the
various types of spectra we described are derived from the same source. We may
distinguish four such types : 1st, the bands, especially seen when the flame of cyanogen
is fed by air ; 2ndly, the particular distribution of light and shadow near H|3 when the
flame of olefiant gas is fed by oxygen ; 3rdly, the large fields shaded by transversal dark
lines ; 4thly, the characteristic groups of bright lines, a, b, c, d, e, f, g, h , which are to
be ranged into two different sets, a, b , c, d, and e, f, g, h. It is a curious fact that all
these different types, either fully developed or indicated only, are represented in the
flame of cyanogen, if fed with oxygen, while in all the other cases we examined there
are represented either a single type or two types, or even three, — namely, 1, the third
type alone ; 2, the first type, with the second set of groups ; 3, the third type, with one
set of groups (a, b , c, d) ; 4, the same type, with the other set ( e , g) ; 5, the second and
third types, with the first set of groups. There is no doubt that the different types
correspond to different degrees of temperature, — the temperature being lowest when the
bands are principally developed, lower in the case of the second set of groups than in
the case of the first, lower in the case of the shaded large fields than in the case where
the characteristic groups appear simultaneously.
In the present state of the question we are not able fully to explain the various
types of spectra of carbon. It is only proved that all spectra which we referred to
carbonic vapour do not contain any bright line belonging to another elementary gas.
Either the well-known spectra of foreign admixed gases, of nitrogen, oxygen, hydrogen,
for instance, do not appear at all ; or if they do, they may be subtracted from the whole
apparent spectrum.
It appears doubtful that the different types depend solely upon temperature. If so,
the temperature varying in the different parts of the ignited vapour of carbon, different
types may be seen simultaneously. We shall not now discuss the influence which the
coexistence of foreign gases might have on the spectra of vapour of carbon, nor may we
here decide whether or not, in the lower temperature of the flame, a gaseous compound
of carbon, not being entirely decomposed, exhibits, with the spectrum of the vapour of
carbon, simultaneously the spectrum of the undecomposed gas.
In the spectrum of cyanogen, for instance, we got no visible traces of the spectrum
SPECTEA OF IGNITED GASES AND VAPOUES.
21
of nitrogen (originating from the decomposed gas), whether we supplied the flame by a
jet of oxygen, or operated in open air; but in both cases there is no reason not to
admit that the bands, which are not seen in the case of any other compound of carbon,
were owing to the undecomposed cyanogen (see no. 61).
57. With regard to the spectrum of hydrogen , we first refer to former observations.
The spectrum one of us obtained by sending the discharge of Ruhmkorff’s small
induction coil through one of his highly evacuated spectral tubes, constructed by
M. Geissler, shows only three bright lines, which he denoted by Ha, H/3, and Hy.
The beautiful red light of the ignited rarefied gas, divided into these three bright lines,
even after having passed through the four prisms of Steinheil’s spectral apparatus,
remains highly concentrated. At a magnifying power of 72, the three bright lines or
small bands thus obtained are well defined. Their apparent breadth is equal to the
breadth of the slit ; consequently, on further narrowing the slit, they approach gra-
dually to mathematical lines. Hence we conclude that, under the above-mentioned
conditions, the length of wave of the light constituting each of the three hydrogen-lines
is constant, and remains so if by widening the slit the lines are expanded into bands.
In referring the middle lines of such bands to the middle line of the direct image of
the slit, we obtain its angle of refraction. It was proposed to employ these middle
lines instead of Fraunhofer’s dark lines of the solar spectrum in determining the indices
of refraction*. This proceeding has since been proved to be very expedient f.
58. Hydrogen permits the electric discharge to pass at a lower tension than other
gases do. When Ruhmkorff’s small induction coil was discharged through a spectral
tube enclosing hydrogen, which was gradually rarefied to the highest tenuity to be
reached by means of Geissler’s exhauster, finally the beautiful red colour of the
ignited gas became fainter, and passed gradually into an undetermined violet. When
analyzed by the prism, Ha disappeared, while H/3, though fainter, remained well defined.
Accordingly light of a greater length of wave was the first extinguished $.
59. Hydrogen shows in the most striking way the expansion of its spectral lines, and
their gradual transformation into a continuous spectrum. When the direct discharge
of Ruhmkorff’s large induction coil is sent even through the old spectrum tubes
enclosing hydrogen, the formerly obtained spectrum is essentially altered. By increas-
ing the power of the coil, the violet line Hy first expands ; while it continues to
expand, the expansion of the bluish-green line H/3 becomes visible. Let the aperture
of the slit be regulated so that the double sodium-line will separate into two single
lines nearly touching one another. Then, the angular breadth of H/3 becoming two or
three minutes, the breadth of Hy is about double. The expansion takes place as well
* Poggendorff’s * Annalen,’ vol. cvii. p. 497.
t Landolt: “Ueber die Breehungsexponenten flUssiger homologer Verbindungen,” Poggendorff’s ‘Annalen/
vol. cxvii. p. 353.
t Plucker : “ Ueber recurrente Strome und ihre Anwendung zur Darstellung von Gasspectren,” Poggen-
dorff’s * Annalen/ vol. cxvi. p. 51.
22
DES. J. PLtJCKEE AND J. W. HITTOEE ON THE
towards the less as towards the more refracted part of the spectrum. Ha remains
almost unchanged after H y has passed into an undetermined large violet band, and H/3
extended its decreasing light on its two sides. On employing the Leyden jar, and
giving to the gas in our new tubes a tension of about 60 millims., the spectrum is
already transformed into a continuous one, with a red line at one of its extremities.
At a tension of 360 millims. the continuous spectrum is highly increased in intensity,
while the red line Ha, expanded into a band, scarcely rises from it. If the electric
spark passes through hydrogen at the ordinary tension, the ignited gas on its way
always gives the spectrum of the three expanded lines*.
60. Even in the old spectral tubes enclosing highly rarefied hydrogen, the ground,
from which the three characteristic lines rise, did not appear always of the same dark-
ness ; in some instances new bright lines appeared, especially in the neighbourhood of
the sodium-line. In resuming the subject, we pointed out the existence of a new
hydrogen-spectrum , corresponding to a lower temperature, but having no resemblance
at all to the spectra of the first order of nitrogen, sulphur, &c. In this spectrum, of a
peculiar character, if fully developed, we observe a great number of well-defined bright
lines, almost too numerous to count and represent by an engraving, but brilliant enough to
be examined at a magnifying power of 72, after the light has passed through four prisms.
* After Fraunhofer, and especially Dr. Wheatstone, directed the attention of philosophers to the electric
spectrum, Masson indicated the red hydrogen-line, hut without referring in an explicit way to its origin.
Angstrom first separated the spectrum of gas from the spectra of metal. In the diagram he gave of the
hydrogen-spectrum, he represented, by means of curves, the intensity of light along the whole length of the
spectrum, especially the maxima of intensity within the red, the green, and the violet. These maxima corre-
spond to Ha, H/3, H y, here expanded into bands, the breadth of which, as well as their decreasing intensity
towards both ends, are indicated by the extension and steepness of the curves. After one of us published
his first researches on the spectra of ignited gases, M. van der Willigen, in operating with strong induced
currents, determined in a similar way the maxima of intensity of the hydrogen-spectrum.
The spectra thus obtained are not calculated to prove the connexion existing between the bright lines of
ignited gases or vapours and Fraunhofer's dark lines of the solar spectrum. Starting, in his first communica-
tion made to the Eoyal Swedish Academy, 1853, from the theoretical conception “ that the dark lines of the
solar spectrum are to be regarded as an inversion of the bright lines of the electric spectrum,” M. Angstrom
concluded the coincidence of Ha with Eraunhoeer’s line C ; but the diagram shows that this conclusion was
not based on exact measurement. One of us, in his publication of 1859, not being guided by any theoretical
view on this point, first announced the coincidence of H/3 with Fraunhofer's E, and fixed the position of Hy
near G, of Ha at a distance of two minutes from C. When at a later period he made use of Steinheil’s large
spectral apparatus, he pointed out at first sight the exact coincidence of Ha with C, Hy with a marked black
line at some distance from G, towards E. In operating with spectral tubes, M. Angstrom confirmed these
results. (The spectroscope employed in 1859 being a small and imperfect one, there was given to the slit an
aperture of more than three minutes. The adjustment was made with regard to H/3. Hence the error finally
made in determining the position of Ha may be fully explained, by the circumstance that the illuminated
border of the slit was observed instead of the illuminated aperture itself.) — Angstrom : “ Optische Hnter-
, suchungen,” Poggendorfe’s c Annalen,’ vol. xciv. ; “ Ueber die ERAUNHOEER’schen Linien im Sonnenspectrum,”
Ibid. vol. cxvii. Yan der Willigen : “ Over het electrische Spectrum, Yerhandelingen der K. Hollandsehe
Academie (Natuurkunde vii. & viii.). Plucxer, Poggendorfe’s ‘ Annalen,’ vol. evii. p. 544.
SPECTRA OF IGNITED GASES AND VAPOURS.
23
61. On sending the direct discharge of Ruhmkorff’s coil through a tube of glass from
one-fourth to one-eighth of an inch in diameter, provided with electrodes of platinum
or of aluminium, enclosing hydrogen at a tension of 5 to 10 millims., a luminous thread
of light of a bluish-white colour was seen passing along the axis of the tube, without
touching the glass. When analyzed by the prism, it gave a faint spectrum of the
above-mentioned numerous bright lines, especially within the red and the yellow.
Among these lines neither Ha nor Hy were seen ; H/3 only appeared, but less bright
than many of the other lines. By interposing the Leyden jar and gradually increasing
its charge (12), all lines became brighter, H/3 surpassing all other lines in brilliancy ;
Ha appeared beautifully, Hy fainter. Hence we conclude that the numerous bright
lines belong neither to the vaporized metal of the electrodes, nor to the decomposed
interior surface of the glass, but solely to the hydrogen, constituting a new spectrum of
it. This spectrum may be seen simultaneously with the three characteristic lines Ha,
H/3, Hy ; but at an increased temperature, when these lines begin to expand, it entirely
disappears.
62. We got only one spectrum of oxygen in operating exactly in the same way as we
did in the case of nitrogen, with merely this difference, that under the same con-
ditions a spectrum of equal brightness was obtained only by means of a stronger
discharge. Accordingly if oxygen, enclosed in the spectral tube, be replaced by com-
mon air, the spectrum of the oxygen it contains does not appear until after interposing
the Leyden jar.
We do not enter here into the detail of the oxygen-spectrum, but conclude with a
general remark. Nearly all luminous lines of the spectra of the second order expand
when the temperature of the ignited gas increases beyond a certain limit ; but neither
do all lines reach the same brightness before expanding, nor do the lines in the different
parts of the spectrum expand at the same temperature. That is seen best in the spec-
trum of the second order of oxygen. The bright lines constituting the characteristic
groups of its middle part oppose the greatest resistance to expansion. If they are best
defined, the luminous lines towards the red extremity, most distinct at a lower tem-
perature, are already expanded, while towards the violet extremity the luminous lines
are scarcely developed ; they will be brightly developed, become well defined, and
extend very far, after the ignited oxygen reaches a temperature at which the groups of
the middle part are expanded. Hence arises the difficulty of representing the oxygen-
spectrum. A drawing exhibiting the well-defined lines successively developed in its
different parts is rather an ideal image than a true representation of nature.
63. Water introduced into a small spectral tube was kept boiling till the last traces of
air were expelled, and then, before all the water was evaporated, the tube was hermetically
sealed. The direct discharge, if passing, scarcely rendered the tube luminous, but with
the intercalated jar the peculiar red light of hydrogen appeared, exhibiting the charac-
istic lines Ha, H/3, Hy well defined. When these lines became gradually expanded,
the lines of the oxygen-spectrum successively appeared with an increasing intensity,
24
DES. J. PLUCKEE AND J. W. IIITTOEF ON THE
finally rising from the hydrogen-spectrum transformed into a continuous one. Here
the heat of the discharge is increased by the increased density of the vapour of
water, and reciprocally the evaporation is accelerated by the rising temperature of the
discharge. The vapour of water is decomposed by the discharge ; the ignited hydrogen
resulting from the decomposition exhibits a spectrum at a lower temperature than the
resulting oxygen does. After the discharge ceases, oxygen and hydrogen are recomposed
again to water.
64. Phosphorus , when treated like sulphur (35), exhibits a beautiful spectrum of the
second order. Whatever may be the gradual change of the intensity of light produced
by regulating as well the discharge as (by means of a lamp) the heat of the spectral
tube, we get only one spectrum of bright lines successively developed. Among them
there is one announcing at first sight the presence of vapour of phosphorus, a triple
orange line, formed by two single lines of first intensity, and a third less bright one
bisecting the interval between them. The other brightest lines are seen within the
green.
We get no difference at all by introducing into the spectral tube either common or
red phosphorus. After the current had passed for some time, common phosphorus was
seen, within the tube, transformed into a subtle powder of the red kind.
65. Chlorine , Bromine , and Iodine were among the substances first submitted to spec-
tral analysis by one of us. On resuming the subject we fully confirmed the formerly
obtained results, that not any two of the numerous spectral lines, characterizing the
three substances, were coincident.
By means of the electric current we got in all instances only spectra of the second
order. We were especially desirous of ascertaining whether there existed a spectrum
of iodine, corresponding to a lower temperature, the inverse or negative image of which
agreed with the spectrum produced by absorption on sending sunlight (which, in order
to prevent the influence of Fraunhofer’s dark lines, may be replaced by the light of
phosphorus in combustion) through a stratum of heated vapour of iodine. Thus,
indeed, we obtain more than fifty shaded bands, the breadth of which decreases from
the violet to the red, constituting a spectrum of the first order. The flame of hydrogen
in open air was not fitted to ignite vapour of iodine introduced into it sufficiently. But
by feeding the flame by oxygen we got a new spectrum. Large fields, shaded by dark
transversal lines, differently bounded, but quite similar to the third type of the spectra
of vapour of carbon, constituted a spectrum of the first order. But the spectrum we
might have expected according to theory was not seen.
66. Arsenic , when treated like sulphur and phosphorus, gives a well-defined spectrum
of the second order.
67. So does mercury when introduced into a spectral tube from which air is expelled,
either by means of Geissler’s exhauster, or by boiling the mercury within it. After a
slight heating of the tube by means of an alcohol-lamp the discharge passes; and
having once passed, it continues to do so, even without the lamp. Vapour of mercury
SPECTRA OF IGNITED OASES AND VAPOURS.
25
opposing a comparatively small resistance to the passing current, we found it useful to
intercalate at the same time a Leyden jar and a stratum of air. Thus, indeed, by regu-
lating as well the density of the vapour as the thickness of the stratum, we obtained
the best-developed spectrum.
The least quantity of mercury, if vaporized, becomes visible by the passing current.
Especially when mixed with other metals like arsenic, antimony, &c., we may detect
even the least traces of it, which would entirely elude chemical analysis. Thus, for
instance, we observed that arsenic, whatever may be its origin, is not free from mercury.
After introducing a small quantity of it, which we heated by an alcohol-lamp when we
placed it before the slit of the spectral apparatus, in a few moments four lines of great
brightness, among which was a double yellow one, rose from a dark ground, but before
the spectrum was fully developed it was abruptly replaced by another quite as brilliant.
The first spectrum obtained belongs to vapour of mercury, first developed by evapora-
tion, the second to arsenic, which increasingly vaporized at a higher temperature dis-
putes the conduction of the discharge with the mercury, the vapour of which, according
to its small existing quantity, reaches only a very low limit. The spectrum of arsenic
remaining alone, gradually increased in brilliancy by the development and expansion of
its bright lines. In cooling the spectral tube, by taking off the lamp, the spectrum of
arsenic lost its extreme brilliancy; well-defined bright lines, the number of which
gradually diminished, rose from a dark ground, and were replaced again by the spectral
lines of mercury, till finally all light was extinguished.
68. The metals of alkalies, sodium, potassium, lithium, thallium show, even at the
lower temperature of Bunsen’s lamp, a spectrum of the second order, consisting of bright
lines, the number of which is increased by the higher temperature of the current, while
the principal ones are expanded.
69. Barium, strontium, calcium show, even in Bunsen’s lamp, shaded bands, and a
bright chief single line at the same time. This line, green in the case of barium, bluish
violet in the case of strontium, violet in the case of calcium, fully exhibits the character
of the bright lines in the spectra of the second order. The bands, if well developed,
constitute a spectrum of the first order. We examined especially the spectrum of
barium, by introducing its chloride into the hydrogen-flame. In making use of two
prisms and employing a magnifying power of eighteen, we distinctly obtained the shading
of the bands resolved into dark lines, finer and closer to one another than in former
similar cases. Thus we proved that the band-spectrum of baryta is in every respect a
spectrum of the first order.
70. Spectra of the first order were observed in the case of a few heavy metals only.
Among these metals we mention in the first instance lead. We obtain its spectrum in
Bunsen’s lamp, but in order to get it beautifully developed we must make use of the
oxyhydrogen flame. The spectra we obtained were identically the same whatever com-
pound of lead was introduced into that flame. We especially examined its combinations
with chlorine, bromine, iodine, and oxygen. In all cases we observed larger bands,
MDCCCLXV. e
26
DRS. J. PLUCKER AND J. W. HITTORF ON THE
which by increased temperature were divided into smaller ones. Each band has a chan-
neled appearance produced by fine dark lines, the darkness of which increases from the
more to the less refracted extremity of the band, contrary to what takes place in the
violet channeled spaces of nitrogen.
Chloride of lead, when examined within our spectral tubes, showed no traces of
bands ; they were replaced by bright lines. But on account of the great difficulty of
vaporizing it, the spectrum of the second order, owing to lead, is best developed by
the discharge of Ruhmkorff’s coil between two electrodes made from this metal and
surrounded by an atmosphere of hydrogen. The spectrum of this gas being under these
conditions nearly a continuous one (59), the bright lines of the lead-spectrum of the
second order rise from a coloured ground. More than fifty lines were counted, although
the fainter ones did not appear.
71. When either chloride or bromide or iodide of copper is introduced into the flame
of Bunsen’s lamp, we get spectra of bands, but these bands are not exactly the same,
they differ from one another by additional bands*. In the oxyhydrogen flame the
bands are better developed, but we did not succeed in resolving the shadows of the
hands into dark lines. At the same time four lines of single refrangibility appeared.
The number of these lines was increased and the number of bands reduced, when chlo-
ride of copper was examined within our spectral tubes. The well-known spectrum of
the second order was fully developed, and every trace of bands extinguished, by dis-
charging Ruhmkorff’s coil between two copper electrodes.
72. Finally, manganese exhibited a curious spectrum of the first order, most similar
to that of carbon (third and fourth type (56)). The whole spectrum is equally divided
into large fields, but these fields are shaded differently by fine transversal lines, the
shadow increasing from the more to the less refracted extremity of each field. From
the brighter less refracted part rise groups of bright lines, similar to the groups of
carbon, but the lines of the groups are differently distributed.
When Ruhmkorff’s large coil was discharged between two electrodes made from man-
ganese (we surrounded them with an atmosphere of hydrogen), a pure spectrum of the
second order, free from any traces whatever of the former spectrum, was obtained.
Explanation of the Plates.
In determining the different spectra both of the first and the second order, the
dispersing prisms occupied invariably the same position, corresponding to the minimum
deviation of the green hydrogen-line H/3, i. e. of Fraunhofer’s F. All spectra repre-
sented in the Plates are referred to the three hydrogen-lines Ha, H/3, Hy, and the
double sodium-line Na. Generally two prisms of about 60° and 45° were employed,
* This fact has been noticed by At. A. Mitscheblich with regard to the chloride and the iodide, and attri-
buted by him to the undecomposed salt (Toggendobff’s ‘ Annalen,’ 1862, vol. ii. p. 299).
SPECTBA OF IGNITED GASES AND VAPOURS.
27
giving the distances of Ha and Na on one side and of Hy on the other side from H/3,
by the following numbers of divisions of an arbitrary scale :
139-6, 100-5-101, 88-5.
In the first Plate portions of all the coloured spectra are represented as they appear
by making use of two additional prisms of 45°.
PLATE I.
contains spectra of the first order. The first spectrum, N, belonging to nitrogen, is
taken under such conditions that both its extremities appear equally developed. To
the whole spectrum is added a representation of two bands, C, of its more refracted
part, obtained by means of the four prisms. Here a determined number of subtle dark
transverse lines produce the channeled appearance. Likewise the configuration of two
orange bands, A, and two green ones, B, is represented, exhibiting the character of the
less refracted part of the spectrum (15-19, 27, 28).
S represents the spectrum of sulphur, as obtained by means of an exhausted bent
spectral tube enclosing sulphur moderately heated by an alcohol lamp, and traversed by
the charge without an interposed jar (35, 36).
Two green and two blue shaded bands, as seen by means of the four prisms, are repre-
sented by A and B.
C I shows the spectrum of vapour of carbon obtained by the combustion of cyanogen
in oxygen. It exhibits within the large shaded fields groups of peculiar bright lines,
the brilliancy of which it was impossible to represent. These groups are denoted by
a , b , c , d, e, f\ g , h. The red extremity becomes fainter when the heat of com-
bustion increases, and even appears more distinct if the combustion takes place in air
(41-46).
The configuration of One of the red bands, as seen when the four prisms are employed,
is represented by A.
C ii exhibits the spectrum of vapour of carbon obtained by means of spectral tubes
enclosing oxide of carbon, the gas being decomposed by the electric discharge (49, 50).
On taking away all characteristic groups, the remaining part of the spectrum, consisting
only of three large shaded fields, is that obtained if the density of the gas be greater
and the discharge too strong (51), as well as in the case of imperceptible traces of
decomposed carbonic combinations (8).
C hi shows the less refracted part of the brightest of the large shaded fields (51).
C iv exhibits a peculiar distribution of light and shade within the violet, scarcely indi-
cated in Ci, but well developed when olefiant gas instead of cyanogen is burnt in
oxygen (48).
28
DBS. J. PLTTCKER AND J. W. HITTOEF ON THE
PLATES II. & III.
represent spectra of the second order, on a scale one-third larger than the scale of
Plate I.
In Plate II. N shows the second spectrum of nitrogen (20-23), O the spectrum of
oxygen (63), S the second spectrum of sulphur (37, 38), Se of selenium (39).
In Plate III. I shows the spectrum of iodine, Br of bromine, Cl of chlorine. Some
remarks may be added here with regard to the conditions under which the spectra are
obtained.
Iodine was introduced into a bent spectral tube, and the tube exhausted as far as
possible. While more recently tubes have been constructed which do not allow the
discharge of Ruhmkokff’s large coil to pass, not even at a very short distance of the
electrodes, the same effect will scarcely be obtained if iodine is enclosed in the tube.
Accordingly the very first moment the phenomena described in art. 8 take place ; but soon
after, vapour of iodine is developed, and by the heating power of the discharge we get,
without the Leyden jar, a spectrum of mere iodine, consisting of very well-defined lines
on a dark ground. After the interposition of the jar these lines became more brilliant,
but remained well defined, and their number increased. Then the position and the
intensity of the lines of the middle part were determined, while the red extremity
was not at all developed, and the violet one most imperfectly. If the density of the
vapour is increased by heating the tube by means of an alcohol lamp, the lines deter-
mined are expanded, while the’ground becomes illuminated. The brilliancy so increases
that the eye can scarcely bear it, till at last the discharge ceases to pass. While the
middle part approaches to continuity, a certain number of delicate brilliant red lines,
seen in the diagram, appear, and do not lose their distinctness as long as the discharge
passes. Towards the violet extremity new lines likewise appear, hut though that extre-
mity becomes most brilliant, we were not able to get the lines well defined. Accordingly
the position of the expanded lines is approximately indicated by dotted lines.
A drop of bromine was introduced into a small exhausted spectral tube. The tension
of its vapour being too great to allow the discharge to pass, the vaporized fluid was
expelled till the remaining vapour obtained a tension of about 6 centimetres. But
by and by the vapour of bromine, combined with the platinum of the electrodes, was
deposited on the interior surface of the tube, and after some time, evidently from want
of sufficient conducting matter, the beautiful spectrum fainted almost suddenly. The
spectrum was taken with the interposed jar. In this case Ha and H/3 are simulta-
neously seen, but expanded, indicating traces of remaining water. The lines of oxygen
are not seen. Without the jar hydrogen is not indicated. Then four bright lines,
belonging to bromine, appear in the neighbourhood of Ha. While, with the interposed
jar, they are fully expanded like this hydrogen-line, a less refracted subtle line appears,
always remaining most distinct. The blue and violet extremity of the spectrum is better
defined than in the case of iodine.
SPECTRA OF IGNITED GASES AND VAPOURS.
29
The spectrum of chlorine is taken under similar conditions with the spectrum of
bromine. The spectral tube most carefully exhausted was several times filled with
chlorine and exhausted again. The final tension of the remaining gas was about 6 centi-
metres, as it was in the former case.
P exhibits the spectrum of phosphorus (64).
We conclude with a general remark regarding more or less all the spectra of the
second order represented in Plates I. & IT. The intensity attributed to the different
bright lines constituting these spectra corresponds to the condition in which they are
best developed.. There seems to be a general rule that all luminous lines become
brighter and are finally expanded, when the heating-power of the discharge continually
increases. But for different lines the intensity does not rise in the same ratio : thus lines
less brilliant at first than others may afterwards surpass them in brilliancy. The inten-
sity attained by the different luminous lines before they are expanded greatly differs ;
lines may disappear by expansion, while others of the same spectrum do not yet appear.
The least-refracted lines generally resist expansion the most.
MDCCCLXV.
F
S pect
Nitrogen
HH
iiiiSili
!
&
m&W;
■
msmH
•t:k|
Spectra secundi Ordinis Ni trojciii^/
Ncl
jj
t
Phil. Trans. MDCCCLXYTlateH.
>ni Oxygen ii Sulphuris Selenii
i.
j
ih_— iL
! i
3.
Si
Engraved and print edT>y A..Henrv. Bonn.
Spectra secundi ordinis ,c
J
B
C
1 1 1
Phil. Trans. MDCCCLXV.PlatellL
i Bromi Chlori Phosphori
in
r
— I — i — L_i J. 1. 1 I I I I
Ensnared anl^rinte.l"by A.Eenrj Bonn.
[ 31 ]
II. On the Osteology of the genus Glyptodon.. By Thomas EL Huxley, F.B.S.
Received December 30, 1863, — Read January 28, 1864,
Part I. — -The history of the discovery and determination of the remains of the Eoplophoridce.
Part II. — -A description of the skeleton of Glyptoclon davipes, Owen ( Hoplophorus Selloi, Lund?).
§ 1. Description of the Skull.
§ 2. Description of the Vertebral Column.
Part I. — The history of the discovery and determination of the remains of the Hoplo-
phoridae, or animals allied to. or identical with , Glyptodon clavipes.
The earliest notice of the discovery of the remains of Glyptodon-Yike animals is con-
tained in the following extract from a letter, addressed to M. Auguste St. Hilaire by
Don Damasio Laranaga, Cure of Monte Video, which appears in a note at p. 191 of the
fifth volume of the first edition of Cuvier’s ‘ Ossemens Fossiles,’ published in 1823: —
“I do not write to you about my Dasypus (Megatherium, Cuv.), because I propose
to make it the subject of a memoir which, I trust, may not be unworthy of the 'atten-
tion of those European savants who take an interest in fossils. I will merely say that
I have obtained a femur, which was found in the Rio del Sauce, a branch of the Saulis
Grande. It weighs about seven pounds, and may be six or eight inches wide. In all
points it resembles the femur of an Armadillo. I will send you one of its scales. The
tail, as you have seen, is very short and very large ; it also possesses scutes, but they
are not arranged in rings, or in whorls. These fossils are met with, almost at the sur-
face, in alluvial, or diluvial, formations of a very recent date. It would seem that similar
remains exist in analogous strata near Lake Merrim, on the frontier of the Portuguese
colonies.”
Cuvier expresses no opinion as to the accuracy, or otherwise, of Don Damasio
Laranaga’s identification of his Dasypus with the Megatherium, an identification which,
it will be seen, was erroneous.
The volume of the Transactions of the Royal Academy of Sciences of Berlin for the
year 1827 contains a memoir by Professor Weiss* upon the collections of fossils and
minerals gathered in South America by Sellow, accompanied by five plates, four of
which display excellent representations of various portions of the dorsal and caudal
dermal armour, and of part of a femur, of one or more species of Glyptodon. Some of
these fossils (the fragments of the dorsal dermal armour) were obtained at three feet
from the surface, in the marly clay of which the banks of the Arapey Chico (a branch
* Ueber das siidliche Ende des Gebirgzuges von Brasilien in der Provinz San Pedro do Sul und der Banda
Oriental oder dem Staate von Monte Video : nach den Sammlungen des Herrn Fa. Sellow, von Herrn Weiss
(Gelesen in der Akademie der Wissenschaften am 9. August 1827, und 5. Juni 1828).
MDCCCLXV. G
32 PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON.
of the Arapey Grande, an affluent of the Uruguay) are formed. The skeleton of the
Megatherium now at Madrid was found in a similar clay which underlies Buenos Ayres.
The femur and the fragment of caudal armour were procured from the banks of the
Quegnay, a more northern affluent of the Uruguay than the Arapey.
Weiss remarks upon these fossils ( l . c. p. 276) “that it can hardly he doubted that
they belonged to no other animal than the Megatherium , Cuv. Cuvier himself pub-
lished, in a note to p. 191 of his ‘ Recherches sur les Ossemens Fossiles,’ t. v. le partie,
the first information which he received, in 1823, that his Megatherium was a loricated
animal. M. Laranaga, parish priest of Monte Video* (from whom this information
was derived, and in whose house M. Sellow, in 1822, saw two fragments of the
armour, one belonging to the back and the other to the tail, which were found between
Monte Video and Maldonado, in a gully opening into the Arroyo de Solis), believed the
animal to be an Armadillo, Dasypus ; Cuvier had already pointed out the similarity of
the extremities to this genus and to Myrmecopliaga. However, the armour plates found
on the Arapey show no trace of a zonary arrangement, and the fragments possessed by
M. L Aran ag a also leaving a doubt on this point, it may remain an open question whether
the Megatherium possessed a veritably jointed armour, or whether it was not more
probably provided with a solid shield.”
The figures show, and Professor Weiss remarks upon, the raised conical form of the
marginal pieces of the carapace.
In the course of his description of the parts of the skeleton of a Megatherium sent to
this country by Sir Woodbine Parish, Mr. Clift f remarks, “ In these latter instances
the osseous remains were accompanied by an immense shell or case, portions of which
were brought to this country ; but most of the bones associated with the shell crumbled
to pieces after exposure to the air, and the broken portions preserved have not been
sufficiently made out to be, at present, satisfactorily described. Representations, how-
ever, of parts of the shell in question are given in the plate annexed.”
The plate (46) to which reference is here made exhibits views of the inner and
outer surfaces of parts of the carapace of a Glyptodon. In a note (p. 437) Mr. Clift
mentions that casts of the principal bones in question have been sent, among other
places, to the Jardin des Plantes at Paris.
The next work upon this subject in the order of time, is the very valuable essay com-
municated by Professor E. D’Alton to the Berlin Academy in 1833 Sellow had
* [“ A friend of natural history and, in every way, an estimable man, who has now unfortunately become
blind,” writes M. Sellow regarding him to M. von Olfers on the 10th October 1829. We can therefore no
longer look for the appearance of his promised essay on these fossil remains.]
t “ Some account of the Remains of the Megatherium sent to England from Buenos Ayres by Woobblne
Parish, jun., Esq., F.G.S., E.R.S.” By William Clift, Esq., E.G.S., F.R.S. Bead June 13, 1832. Transactions
of the Geological Society, vol. iii. 2nd series.
t “ Ueber die von dem verstorbenen Herrn Sellow aus der Banda Oriental mitgebrachten fossilen Panzer-
Eragmente und die dazu gehorigen Knochen-Ueberreste,” with four plates. The volume of the * Abhand-
lungen der Koniglichen Akademie der Wissenschaften,’ in which this essay appears, was published in 1835.
PROFESSOR HUXLEY OH THE OSTEOLOGY OF THE GENUS GLYPTODON. 33
been compelled by the local authorities to send to Bio Janeiro all the bones and the
finest pieces of the carapace, which he discovered in association with the fragments of
dermal armour figured by Weiss*; but, by good fortune, these additional materials at
length found their way into the Berlin Museum, and afforded D’ Alton the materials
for his memoir, in the first section of which the pieces of the carapace of the fossil
animal are described ; while the second section is devoted to an account of the structure
of the dermal armour of living Armadillos, and the third to a description of the
fossil bones found in juxtaposition with that dermal armour.
The results of the comparison of the fossil armour with that of existing Armadillos
are thus stated : —
“ If we compare these fossil dermal plates with those of living species of Dasypus , it
becomes obvious that all the peculiarities of the former may be paralleled by the latter;
but with this difference, that while, as appears from Sellow’s report, all the fossil plates
belonged to one and the same animal, their peculiarities are not all found associated
together in any one living species. The majority of the fossil plates which were distant
from the margin, e.g. those represented by Weiss in figs. 1, 4, & 5, and many described
above, exhibit the greatest similarity to the dermal plates of Dasypus niger ; and thence
it may be concluded that the epidermis of the Dasypus of the ancient world (if for
brevity’s sake I may so name the animal), like that of the Dasypus niger , was divided
differently from the bony plates, and that strong hairs were arranged in the interstices
of the epidermic scales.
“ The pieces which belonged to the edge, or the pointed marginal scutes (Zacken),
most nearly resemble those of D. Poyou (fig. 12 of our first Plate), and D. grandis shows
a somewhat similar formation. In addition, the thoracic shield and the moveable zones
of D. villosus (fig. 18) are also provided with pointed marginal scutes; and, according to
Azara, the Tatou pichey exhibits similar structures. But in all the animals provided
with such pointed scutes, they are directed from above, and forwards, downwards, and
* Professor Owen writes (On the Olyptoclon clavipes, Geol. Trans, vol. hi. pp. 82, 83), “ The portions of
the tessellated bony armour figured by Professor Weiss, pi. 1 and 2, and described at p. 277 of his memoir,
were obtained by Sellow' on the Arapey-Chico in the province of Monte Yideo ; but no bones either of the
Megatherium, or any other animal, are mentioned as having been associated with them. A third series of fossils,
in which fortunately some bones of the extremities were discovered associated with the tessellated bony case,,
was presented to Sellow by the President of the province of San Pedro, with the information that they had
been originally discovered in the proximity of Rio Janeiro.”
■ This, however, appears to be a misapprehension of the state of the case.. The armour figured by Weiss in pi. 1
and 2 of his memoir, and the “ third series of fossils ” were associated together : and so far from the President
of the province of San Pedro having presented anything to Sellow, it was Sellow who was obliged to present
the fossils to the President, or at any rate, to dispose of them according to his orders. “ Denn die Aufforderung.
des damaligen Prasidenten der Provinz San Pedro, des Yisconde des S. Leopoldo, nothigte ihn [Sellow] den
hauptsachlichsten Theil dieser fossilen Ueberreste nach Rio Janeiro abzuliefern.”
It is therefore sufficiently obvious that the fossils were not found at Rio Janeiro, but were sent to that
place from Arapey-Chico.
G 2
34 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
backwards ; and therefore some of the fragments may be referred to the left, and some
to the right side From the preceding comparisons it follows that the fossil scutes are
similar to those of the thoracic and pelvic shields of different living Armadillos, although
they differ from them in many respects. But if objections should still be raised to regard-
ing the animal which bore the fossil armour as an Armadillo (Giirtelthier), two replies
may be made. In the first place, neither the entire skeleton nor the perfect shell of
the animal have been obtained. Of the skeleton, the vertebral column, the ribs, and
sternum are wanting — or exactly those parts which the moveable zones (Gurtel) would
have covered. Secondly, the moveable zones themselves, although among the charac-
teristic features of the Armadillos, are of less importance than was formerly believed,
as Azara has already pointed out.”
The state of the bones indicated that they appertained to a young animal, the epi-
physes being distinct. Those described belonging to the fore limb are, a part of the
scapula (?), the distal end of the left humerus, the radius and ulna, nearly perfect, and
eighteen bones of the fore foot. Of the latter, five belonged to the carpus, of which the
three proximal are interpreted by D’Alton as the semilunare (Mondbein), cuneiforme
(das dreieckige Bein), and pisi forme (Erbsenbein). I shall endeavour to show, in the
course of my description of the specimen which forms the subject of this memoir, that
the determinations of the semilunare and cuneiforme are perfectly correct, but that the
so-called pisiforme is not rightly named. The distal bones are, according to D’Alton’s
interpretation, which I can fully confirm, the magnum and the unciforme.
Two entire metacarpal bones, and fragments of another, are considered by the author
of the memoir to correspond with the third, fourth, and fifth of an ordinary five-toed
fore foot ; but they are really the second, third, and fourth, Professor D’Alton having
taken the surface of the cuneiform, which articulates with the fifth metacarpal, for the
surface of articulation with the pisiform. The phalanges of the digits belonging to these
metacarpal bones, and three of their sesamoid bones, are carefully described and figured.
The resemblances of the bones of the forearm with those of the existing Armadillos
are pointed out, especial weight being laid upon the extension of the cuneiform round
the unciform, and its articulation with what D’Alton supposes to be the fifth meta-
carpal ; and certain analogies of the fore foot with that of the mole are indicated.
A fragment of the distal end of a leg-bone, the seven tarsal bones, the four outer
metatarsal bones ; their digits, except the ungual phalanges ; and some other bones of
the hind foot, in a more or less fragmentary state, are described and figured, and atten-
tion is drawn to the remarkably short and strong character of the foot.
In conclusion B’Alton remarks, “Though, as I have endeavoured to show above,
there is a certain agreement between the manus of the fossil animal and that of the
Armadillos, yet the foot shows us no greater similarity than may be observed between
it and many other five-toed animals. Hence the osteology of the primeval animal does
not afford a sufficient confirmation of the view which we derived from the consideration
of the carapace, viz. that the bones, together with the fragments of dermal armour.
PKOEESSOK HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON. 35
might have belonged to an animal nearly allied to the Armadillos, or perhaps even to a
very large, probably extinct, species of Dasypus. The fossil bones are too few to afford
a safe foundation for so decided an opinion respecting the zoological affinities of the
animal. A tolerably perfect skeleton is necessary in order to enable us, from the bones
alone, to draw a safe conclusion as to the structure pf the remainder of an animal.”
Singularly enough, D’ Alton does not mention the Megatherium throughout this paper,
which however affords, by implication, an ample demonstration that the bony armour
described has nothing to do with that animal*.
In 1836, Laurillard, in editing the eighth volume of the second edition of Cuvier’s
‘ Ossemens Fossiles,’ appends the following note to the letter of Don D. Laranaga, quoted
above : —
“ It is very possible that the Megatherium was, in fact, covered by a scaly cuirass ;
but the great fragments which have been found must not be hastily attributed to it ; for
the plaster casts sent from London f prove that an Armadillo of gigantic size coexists
with the Megatherium on the plains of Buenos Ayres. These characteristic fragments
consist of a calcaneum, an astragalus, and a scaphoid, which depart from those of existing
Armadillos only in size, and by purely specific differences.”
In 1836, then, it was clearly made out that the cuirassed extinct animal of South
America is not the Megatherium and is allied to the Armadillos. However, Dr. Buckland,
whose Bridgewater Treatise appeared in this year, and who therefore could hardly have
been acquainted with the views of D’Alton and of Laurillard, still associated the
dermal armour with the Megatherium — supporting his views by an elaborate and inge-
nious teleological argument, which, like most reasonings of the kind, appeared highly
satisfactory. But, in 1837, all further doubt upon the subject was removed by the dis-
coveries of Dr. Lund, who, in that year, despatched to Copenhagen the second of the
remarkable series of memoirs in which he reconstructed the ancient Fauna of Brazil J.
In this paper Dr. Lund established the genus Hoplopliorus upon the dermal armour and
certain bones of an edentate quadruped closely allied to, if not identical with, the
“ Dasypus ” of Laranaga.
Hoplophorus euphractus , the sole species of the new genus described in the memoir,
was estimated by its discoverer to be of the size of an ox, and to have been provided
with a carapace most nearly resembling that of Tolypeutes, but of an astonishing thick-
ness. The extremities are said to have the general structure of those of the Armadillos,
* Thus Muller says in his memoir on the hind foot, cited below, “ In der letzten Abhandlung ist von
Herrn D’ Alton bewiesen, dass der Panzer nicht dem Megatherium angehort.”
t Vide swpra, p. 32. Mr. Pentland appears to have been led to the same opinion by the examination of
these casts in 1835. See Transactions of the Geological Society, vol. vi. ser. 2nd, p. 85, and Mr. Pentlaxd’s
letter to M. Aeago in the ‘ Comptes Rendus’ for March 11, 1839.
£ “ Blik paa Brasiliens Dyreverden for sidste Jordomvaeltning. Anden Afhandling : Patte dyrene. Lagoa
Santa, 16de Novbr. 1837,” published in ‘ Det Kongelige DanskeYidenskabernes Selskabs Naturvidenskabelige og
Mathematiske Afhandlingar,’ Ottende Deel, 1841, p. 70. A notice of Lund’s labours, containing the names of
his genera, is to be found in the ‘Oversigt over det Kongelige Danske Yidenskabernes Selskabs Fordhandlingar
i Aaret 1838/ published by Oksted, the Secretary of the Academy.
36 PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON.
the feet being short and thick, with remarkably broad and short nails ; so that they must
have resembled those of an Elephant, or a Hippopotamus. The skull was sloth-like, and
its jugal arch exhibited the structure characteristic of those animals. The teeth were
similar to the molars of Ccvpybara, but simple instead of being made up of many plates.
Professor Bronn, publishing the .second edition of his 4 Lethsea Geognostica ’ in the
spring of 1838, and unacquainted with Lund’s labours, proposed the name of Chlamy-
dotherium for the animal to which the carapace described by Weiss and D’Alton
belonged, in case the foot should really appertain to it ; and Orycterotherium , in case the
foot should belong to a different animal.
In March of the same year, it appears that M. Vilardebo, Director of the Museum
of Monte Video, and M. Isabelle published conjointly, in Nos. 2551, 2553, and 2555 of
a journal, the ‘ Universal,’ an account of an animal which they had discovered on the
Pedernal, in the Department of Canelones*.
After removing a thin layer of clay, these observers met with a shield formed of pieces
of bone separated from one another by a slight interval ; these pieces, 25 to 50 millimetres
in diameter, and varying in thickness from 12 to 40 millimetres, were hexagonal: the
largest occupied the dorsal region of the carapace, and the smallest its lateral regions.
Each polygon presented a central disk (14 to 27 millimetres in diameter), from whence
radiated six or eight lines, between which as many quadrangular arese were left. These
pieces of bone were symphysially united so as to form a very regular mosaic : the cara-
pace appeared to be fringed with conical pieces forming a semicircle of 24 centimetres.
The carapace was about 4 metres wide, and was as convex as a cask. The bones dis-
covered in it were lumbar vertebrae and pelvic bones. In another place was discovered
a femur about 0-57 metre long, with many plates of the carapace, and a tail formed of
a single mass of bone (covered nevertheless by pieces soldered together), in the middle
of which were widely separated caudal vertebrae. The tail was more than 0-50 metre
long, and more than O' 36 metre in diameter at the base.
Tire authors discuss the question — to what class do these fossils belong 1 — with much
sagacity, and conclude by expressing the opinion that they appertain to a species of
Dasypus , which they term I), antiquus, and which they briefly characterize as follows :
44 Cingulis dorsalibus nullis: verticillis caudalibus nullis.”
The volume of the Transactions of the Danish Academy, already cited, contains
another communication from Dr. Lund, dated Lagoa Santa, September 12, 1838, in
which he speaks of the fossils described by D’ Alton, and identifies the animal to which
they belonged, generically, with Hoplophorus, though he regards it as a distinct species,
and names it Hoplophorus Selloi. Accompanying this paper are sundry figures of parts
of the carapace and of bones of the hind foot of Hoplophorus.
Dr. Lund returns to the subject in a long letter addressed to M. V. Audouin, dated
the 5th of November 1838 (extracts from which are published in the 4 Comptes Rendus ’
for the 15th of April 1839), which contains an enumeration, with brief descriptive
notices, of the seventy-five species of fossil Mammalia which this untiring explorer had
* See the Bulletin de la Societe Geologique de France, t. xi. p. 159 (1840).
PROFESSOR HUXLEY ON THE OSTEOLOG-Y OF THE GENUS GLYPTODON.
37
extracted in the preceding five years from the caverns of Brazil. Among the rest the
writer describes : —
“ 6°. Hoplophorus , a genus very remarkable for the heavy proportions of its species,
for their gigantic size, as well as for the singular manner in which it combines different
types of organization ; however, their characters approximate them most nearly to the
Sloth family. These strange animals were armed with a cuirass which covered all the
upper part of the body, and which was composed of little hexagonal scutes, except in
the middle of the body, where the scutes took a quadrate form, and were disposed in
innumerable transverse bands. The bones of the trunk, as well as the great bones of
the extremities, are also very similar to those of the Tatous, and particularly to those of
the Cachicames ; but the bones which compose the feet are so shortened and have their
articular faces so flattened, that nothing similar is to be seen in any animal skeleton,
and that it is inconceivable how such feet should have been used in digging. The form
of the teeth also indicates that these singular animals could feed only on vegetable sub-
stances, and it is to be supposed that they grazed after the fashion of the great Pachy-
derms. However this may be, the Hoplophorus , of which M. Lund describes two species,
present the peculiarity, hitherto regarded as special to the Sloth, of having a descending
branch to the zygomatic arch. These two species were as large as an ox. Fragments
of the skeletons have already been described by MM. Weiss and D’Alton of Berlin.” —
Loc. cit. pp. 572, 573.
A summary of Lund’s researches, despatched by him from Lagoa Santa on November
5, 1838, and published in the Ann ales des Sciences Naturelles for 1839, under the title
of “ Coup d’ceil sur les especes eteintes de mammiferes de Bresil : extrait de quelques
memoires presentes a l’Academie Boyale des Sciences de Copenhague,” gives a sub-
stantially similar account of Hoplophorus. The species Hoplophorus Selloi is identified
with the cuirassed animal described and figured by Weiss and D’Alton.
The sixth volume of the second series of the Transactions of the Geological Society
contains an elaborate memoir by Professor Owen* on the bones associated with the
dermal armour, figured by Mr. Clift in the memoir already cited ; and on certain teeth,
upon which the genus Glyptodon was founded by the same writer, in Sir Woodbine
Parish’s work on Buenos Ayres 'j*.
Professor Owen considers these remains to be specifically identical with those collected
by Sellow, and described by Weiss and D’Alton ; so that if Lund was right in ascribing
the same fossils to his genus Hoplophorus, Glyptodon becomes a synonym of the latter.
In the memoir under consideration the general form and the minute structure of the
* “ Descriptions of a tooth and part of the skeleton of the Glyptodon clavipes, a large quadruped of the eden-
tate order, to which belongs the tessellated bony armour described and figured by Mr. Clift in the former volume
of the Transactions of the Geological Society, with a consideration of the question whether the Megatherium
possessed an analogous dermal armour.” By Richard Owen, Esq., F.G.S., F.R.S. (Read March 23rd, 1839 :
an abstract of this paper appeared in No. 62 of the ‘ Proceedings.’)
f * Buenos Ayres and the provinces of the Rio de la Plata,’ 1838, p. 178 e.
38
PEOFESSOE HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
teeth, the distal end of the humerus, the radius, two phalanges of the fore foot, “ the
anchylosed distal extremities of the tibia and fibula, an astragalus, calcaneum, seaphoides,
cuboides, external cuneiform bone, the three phalanges of the second toe, and the mid-
dle and distal phalanges of the third and fourth toes, with a few sesamoid bones,” all
belonging to the left side, are described ; while the tooth and the bones of the leg and
foot are figured.
Professor Owen considers that the dental characters “ seem to indicate a transition
from the Edentata to the pachydermatous Toxodon ,” and sums up his general conclu-
sions as to the affinities of Glyptodon thus : —
“ It may be concluded, therefore, that the extinct edentate animal to which belongs
the fossil tessellated armour described by Weiss, Buckland, and Clift, cannot be called
an Armadillo, without making use of an exaggerated expression, and still less a species
of Megatherium ; but that it offers the type of a distinct genus, which was much more
nearly allied to the Dasypodoid than to the Megatherioid families of Edentata, and most
probably connected that order of quadrupeds with the heavy coated Rhinoceros of the
Pachydermatous group” (l. c. p. 96).
In the same year (1839) Professor D ’Alton proposed for the animal, the remains
of which he had originally described, the name of Pacliypus ; so that by this time no
fewer than six names had been applied to mammals all of which are certainly closely
allied to the Hoplophorus of Lund, whether they are, or are not, generically identical
with it, and which may therefore be appropriately termed Hoplophoridce.
In 1845 Professor Owen returned to the Glyptodon question, in the ‘Descriptive and
illustrated Catalogue of the Fossil Organic Remains of Mammalia, and Aves contained in
the Museum of the Royal College of Surgeons of England.’
It is here stated (p. 107) that “those specimens of the present genus which were
presented to the College by Sir Woodbine Parish are from a low marshy place, about
five feet below the surface, in the bank of a rivulet, near the Rio Matanza, in the
Partido of Canuelas, about twenty miles to the south of the city of Buenos Ayres.”
The parts thus found associated are not stated, with the exception of the bones of the
left hind leg and foot (p. Ill), to have belonged to the same individual. They consist
of a molar tooth, part of the left ramus of the lower jaw, a fragment of the humerus,
the left radius, a metacarpal bone and two phalanges, the shaft and distal epiphyses of
the femur (1), the anchylosed distal ends of the tibia and fibula, and numerous bones
of the left hind foot. These had already been described and figured in the Geological
Society’s Transactions.
As new specimens, there are described and figured an almost, entire carapace of
Glyptodon clavipes, from the Pampas of Buenos Ayres, and many dermal bones, all of
which are marked “ Purchased,” and appear not to have been accompanied by bones
of the endoskeleton. Nos. 551, 552, 554, 555, 556, 557 are fragments of carapace,
all presented by Sir W oodbine Parish, and obtained from the locality mentioned above.
They are ascribed by Professor Owen to no less than three distinct species, however,
PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON. 39
viz. Glyptodon clavipes, G. reticulatus, and G. ornatus ; a fourth species, G. tulerculatus,
is based upon purchased specimens, from the Pampas of Buenos Ayres, the precise
locality of which is not stated.
The fact that the dermal ossicles of three species of Glyptodon were found in the
same locality as the bones described, and the absence of any evidence demonstrating the
association of the ossicles ascribed to G. clavipes, rather than those attributed to the
other species, with the bones, throws, it will be observed, some doubt upon the certainty
of that ascription, and opens the question whether the bones really belonged to one form
of carapace or to another.
Of the Plates which illustrate the c Catalogue,’ the first contains a side view, partly
restored, of the Glyptodon clavipes ; the second, views of the carapace and tail ; the
third, of the skull ; the fourth and fifth, of parts of the carapace ; and the description of
the Plates comprises accounts of the structure of the skull and of the tail, parts which
had not been received until after the printing of the body of the catalogue.
In what locality the skull and the tail were obtained, and upon what evidence they
are ascribed to the particular species, G. clavipes , is not stated. The lower jaw and the
defensive bony covering of the skull in plate 1 “ are restored on the authority of an
original sketch of an entire specimen of this species of Glyptodon transmitted to Sir
Woodbine Parish from Buenos Ayres.” The bones of the fore foot are given in outline
after D’Alton.
On the 8th of June, 1846, the late Johannes Muller read a short paper to the Ber-
lin Academy upon the bones of the leg and hind foot described by D’Alton, which
had been worked out and mounted by the help of Professor Owen’s memoir. This
paper, accompanied by an excellent plate, was published in 1849*.
The number of the ‘ Comptes Bendus ’ for August 28, 1855, contains a “ Description
d’un nouveau genre d’Edente fossile renfermant plusieurs especes voisines des Glypto-
dons, et classification methodique de treize especes appartenant a ces deux genres,” by
M. L. Nodot, Director of the Museum of Natural History at Dijon; and this essay,
enlarged and illustrated with plates, appeared two years later in the 4 Memoires de
l’Academie Imperiale de Dijon,’ Deuxieme Serie, tom. v. 1857f.
M. Nodot, in his introductory remarks, states that Vice-Admiral Dupetit brought
back from Monte Video, in 1846, a great number of fossil bones which had been
collected by Dr. Numez on the banks of the river Lujan, and were given to the
Vice-Admiral by the orders of the Dictator Rosas. Admiral Dupetit presented most
of these remains to the Museum of the Jardin des Plantes in Paris ; but dying before
* “ Bemerkungen fiber die Fussknoehen des fossilen Giirtelthiers ( Glyptodon clavipes, Ow.),” Abhand-
lungen d. Konigl. Akad. d. Wissenschaften, 1849.
t Under the title “ Description d’un nouveau genre d’Edente fossile renfermant plusieurs especes voisines
du Glyptodon, suivie d’une nouvelle methode de classification applicable a toute l’histoire naturelle et speciale-
ment a ces animaux. Avec un atlas de douze planches lithographiees.”
MDCCCLXV. H
40 PROFESSOR HUXLEY ON THE OSTEOLOGY- OF THE GENUS GLYPTODON.
he had disposed of all, his widow bestowed two boxes full of detached dermal ossicles
on the Dijon Collection. Out of these, by dint of four months’ constant toil, M. Nodot
reconstructed the carapace.
Subsequent investigations in the store-rooms of the Jardin des Plantes revealed almost
the whole of the tail, and many important parts of the skeleton, of what M. Nodot
believed to be the same individual animal, mixed up, however, with fragments of Mylo-
don, Megatherium , and Scelidotherium. Besides these, M. Nodot found the tolerably
complete extremity of the tail of another individual of the same genus in the Geological
Gallery, and the right half of a lower jaw with the teeth, which he judged to belong to
this individual.
The bones which M. Nodot, guided as it would seem chiefly by their colour, identi-
fies as belonging to the same individual with the carapace, are, “ the lateral and poste-
rior part of the cranium, the occiput, the meatus auditorius, the zygomatic arch and its
long apophysis, three alveoli, and the sagittal crest ; the atlas, the axis, the vertebra of
the fifth ring of the tail ; the two femora entire ; the tibiae and fibulae anchylosed ; the
calcanea; the astragali ; the other tarsal bones ; the left metatarsus ; the three external
toes of the left hind foot ; the left radius ; the ungual phalanx of one of the digits of
the fore foot ; and the ungual phalanx of an internal toe of the hind foot.” The cara-
pace and the tail are fully described by M. Nodot, who considers their peculiarities
sufficient to justify him in establishing for these remains the new genus Schistopleuron.
How far he was justified in so doing is a point which must be discussed at the end of
this memoir ; but there can be no question that “ Schistopleuron ” is one of the IIoplo-
phoridce, closely allied to Glyptodon clavipes ; and hence M. Nodot’s descriptions of the
mandible, sternum, and femur constitute substantial additions to our knowledge of the
organization of that family.
The mandible is unlike the sketch furnished to Professor Owen and adopted by him,
but very like that which will be described below. The first piece of the sternum and
the first two ribs were so anchylosed together as to leave no trace of their primitive sepa-
ration.
On the 14th of November, 1862, 1 presented to this Society a “ Description of a new
Specimen of Glyptodon, recently acquired by the Royal College of Surgeons of England,”
which was published in the fifty-third Number of the ‘ Proceedings of the Royal Society.’
The remains of the specimen, described briefly in this preliminary notice and, in full, in
the present memoir, were presented to the Royal College of Surgeons by Senor Don
Maximo Terrero, having been discovered in 1860 on the estate of his brother, Senor
Don Juan N. Terrero, which is situated on the banks of the river Salado, in the
district of Monte, in the Province of Buenos Ayres, and about eighty miles due south of
the city of that name.
No portions of any other animal, nor any duplicate bones, have been discovered among
the osseous relics the description of which has been entrusted to me by the authorities
PEOEESSOE HUXLEY ON THE OSTEOLOG-Y OF THE GENUS GLYPTODON. 41
of the College of Surgeons — a circumstance which justifies the belief that they all
belonged to one and the same animal, and gives them a peculiar value, the more
especially as there can be little doubt of the specific identity of the new specimen
with the animal to which the skull ascribed by Professor Owen to Glyptodon clavipes
belongs.
I have thus been enabled to add to what was already known of Glyptodon clavipes,
descriptions of the most essential peculiarities of the fore part of the skull, the entire
palate, the mandible, the greater part of the spinal column, the pelvis, and the com-
plete fore and hind feet, and to announce the existence, in this animal, of a conforma-
tion of the spinal column hitherto unknown in the Mammalian, and, indeed, in the
Vertebrate series — the last cervical and two anterior dorsal vertebrae being anchylosed
together into a single osseous mass articulated by ginglymi with the rest of the vertebral
column. As another very remarkable peculiarity of this genus, I have pointed out the
extraordinary characters of the pelvis, and the fact that the cuneiform bone in the carpus
articulates with two metacarpal bones, the fourth and fifth, while the unciform does not
articulate with the fifth at all.
Since the appearance of my paper in the 6 Proceedings of the Royal Society,’ and in-
deed not until the months of May and June 1863, M. Serres, apparently unacquainted
with what had been done in these matters, has redescribed the joint between the second
and third dorsal vertebrae, though he appears to be still unaware of the existence of the
4 trivertebral bone.’ In addition, M. Serres makes known the interesting circumstance,
that the posterior edge of the manubrium of the sternum, anchylosed (as M. Nodot had
pointed out, though M. Serres does not refer to him) with the first pair of ribs, pre-
sents two concave articular facets, by which it was united with the rest of the sternum,
which must have presented two convex surfaces adapted to the foregoing in order to
allow of a movement of flexion. M. Serres is of opinion that this mechanism is
intended to allow of the retraction of the head : “II est done vraisemblable qu’au
moment du danger, peut-etre meme que dans le repos ou le sommeil, le Glyptodon
flechissait le col pour ramener la tete sous la coupole de la carapace”*.
In his second communication to the Academy, M. Serres still speaks of the “anchy-
losis of the first two dorsal vertebrae ” onlyf .
Professor Burmeister, Director of the Museum at Buenos Ayres, has been good
enough to communicate to me a letter, addressed by him to the Editor of the 4 Nacion
Arjentina’ on the 5th July, 1863, commenting upon a lecture upon the Glyptodon
which I delivered before the President and Council of the Royal College of Surgeons,
which was published in the Medical Times and Gazette for the 28th of February and
* “Note sur deux articulations ginglymo'ides nouvelles existant chez le Glyptodon, la premiere entre la
deuxieme et la troisieme vertebre dorsale, la seconde entre la premiere et la deuxieme piece du sternum. Par
M. Sebkes” (Comptes Eendus, May 11, 1863).
t “ Deuxieme Note sur le developpement de 1’ articulation vertebro-stemale du Glyptodon, et les mouvemens
de flexion et d’ extension de la tete chez cet animal fossile. Par M. Sekbes” (Comptes Eendus, June 1, 1863).
H 2
42 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
7th of March, 1863, and which contains the substance of the statements previously-
published in the ‘Proceedings’ of this Society.
Professor Bukmeister affirms that the skeleton of the Glyptodon in the Museum of
Buenos Ayres is much more perfect than that in the lloyal College of Surgeons ; that
it has the seven cervical vertebrae complete ; and that the five middle cervical vertebrae
are anchylosed together, while the seventh is very delicate and fragile. Under these
circumstances, it would appear that Professor Burmeister considers the trivertebral
bone (my description of which he confirms) to be composed of the three anterior dorsal
vertebrae.
Professor Burmeister is further of opinion that the peculiar mechanism of the joint
formed by the trivertebral bone with the rest of the spinal column has not that respi-
ratory function which I have ascribed to it; but, with M. Serres, he thinks that its
object is to allow of the application of the cephalic shield to the anterior aperture of
the shield of the body. Professor Burmeister goes on to remark —
“ As little do I agree with Mr. Huxley as to the immobility of the ribs, which are
wholly wanting in the London skeleton. The skeleton of the Museum of Buenos
Ayres has nine ribs, three of which being complete, prove that they possess a certain
mobility, moving downwards and backwards on their articulations with the spinal column,
as in other Mammalia, but without doubt in a manner somewhat different from the
ordinary way.”
I am at a loss to divine on what grounds Professor Burmeister ascribes to me the
opinion that the ribs are immoveable, and why he affirms that they are wholly wanting-
in the London skeleton. What I have stated is, that the first rib is immoveable ; and
so far from the ribs being wholly wanting, I have particularly mentioned their presence *,
and have alluded to the characters of the first *f\
Professor Burmeister adds that I am in error in supposing that the dorso-lumbar
vertebrae were immoveably united. I believe, however, from Professor Burmeister’s
own words, that my description is substantially accurate. These words are : —
“ There exists a moveable place between the dorsal and the lumbar vertebrae, though
the mobility is not so complete as that of the three first anchylosed vertebrae upon the
following ones. In this part, the skeleton of Buenos Ayres presents a complete column,
formed by eleven vertebrae incorporated into a solid piece, of a very peculiar form, with
three crests in the upper part, the two lateral of which bear the ribs in articular exca-
vations. The total number of dorsal vertebrae and of ribs is therefore fourteen. Then
follow on these the lumbar vertebrae, all anchylosed together and immoveably united
with the sacrum.”
I do not venture to doubt the accuracy of Professor Burmeister’s description of the
specimen under his own eyes ; but nevertheless, as will be seen by-and-by, it is also true
that the account I have given of the Glyptodon in the College Museum is quite accu-
rate. And indeed, as Professor Burmeister admits that all the dorsal and all the
* Proceedings of the Royal Society, Z. c. p. 317. t Ibid. p. 319.
PROFESSOR HUXLEY ON THE OSTEOLOGY OP THE GENUS GLYPTODON. 43
lumbar vertebrae respectively were anchylosed together, with only an imperfect mobi-
lity at the junction of the two solid masses, I do not see how, in any important respect,
his view of the matter differs from mine.
The last criticism which Professor Burmeister offers, refers to what he terms my error
in ascribing five toes to the fore foot, when, as he affirms, it possesses only four. Pro-
fessor Burmeister states that I have figured five toes to the foot of the Glyptodon in the
lecture already referred to ; but he is mistaken ; only four toes are there represented,
numbered, according to the digits of the typical foot which they represent, 2, 3, 4, 5.
In the ‘ Proceedings’ (p. 325) I have expressly stated —
“The trapezium possesses only a very small double articular facet on its palmar face.
If this gave support to a metacarpal, it must have been very small ; and as at present
neither it nor any of the hallucal phalanges have been discovered, it is possible the
pollex may have been altogether rudimentary. In any case the pollex must have
been so much smaller and more slender in proportion than that of Dasypus, that the
animal must have had a practically tetradactyle fore foot.”
The errors, therefore, to which Professor Burmeister adverts, appear to me to arise
to a great extent from his not having rightly comprehended my statements ; and in part,
it may be, from our having to deal with different objects.
Part II. — Description of the Skeleton of Glyptodon clavipes, Owen ( Hoplophorus Selloi,
Lund 1).
The materials which have been available for the following description of the osteology
of Glyptodon are, in the first place, the skeleton referred to in the previous section
as having been presented by Senor Terrero to the Royal College of Surgeons;
secondly, the detached parts which have been already described by Professor Owen, and
are now contained in the Museum of the Royal College of Surgeons ; thirdly, some
fragmentary specimens in the British Museum ; and fourthly, photographs of a skeleton
of Glyptodon in the Museum of Turin. The two latter sources of information, however,
are of altogether secondary importance, and will be adduced merely in confirmation of
the results obtained from the study of the two former series of materials, — in treating
of which, I shall speak of the fragments of Glyptodon clavipes described by Professor
Owen as the “ type specimen,” and of the skeleton presented by Senor Terrero as the
“ new specimen.”
§ 1. Description of the Skull of Glyptodon clavipes.
In the new specimen * the anterior part of the skull, from a line drawn transversely,
immediately behind the zygomatic processes, to the anterior end of the snout, is in a
remarkably good state of preservation — the boundaries of the anterior nares, the antero-
lateral parts of the maxillary bones, the nasal, and the fore part of the frontal, bones
being quite uninjured. Behind the imaginary transverse line in question this cranium
* Plate IY, figs. 1 & 3, Plate V., and Plate YI. figs. 1, 2, 4, & 5.
44 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
is very imperfect — the entire roof and sides, and the greater part of the base of the
skull being absent, while a small portion only of the sphenoidal region is preserved.
Of the facial bones, those entering into the palate are preserved almost in their
entirety, and one ramns of the lower jaw is nearly complete. This skull therefore
supplies almost all those parts which were wanting in the cranium of the type speci-
men, in which the whole of the roof of the skull, from the nasal bones to the supra-
occipital inclusive, most of the exoccipital, alisphenoidal, and orbitosphenoidal regions
of the lateral walls, and of the basioccipital, basisphenoidal, and presphenoidal parts
of the base, together with the temporal bones, are in good condition, while the premax-
illary, maxillary, and palatine bones, with the mandible, are absent.
In order to give a tolerably complete view of the structure of the skull, I shall, in the
first place, describe that of the new specimen ; I shall next proceed to a comparison
of the parts common to this fossil and the skull of the type specimen, in order to
demonstrate the specific identity of the two ; and then I shall endeavour to supply what
is wanting in the new specimen by information derived from the study of the type.
The skull of the new specimen of Glyptodon clavipes. — The anterior nares have a
trapezoidal form, the upper of the two parallel sides of the trapezoid being nearly three
times as long as the lower, so that the two lateral boundaries converge from the roof
towards the base of the nares (Plate VI. fig. 1).
The upper boundary of the anterior nares is formed by the anterior edges of the thick
nasal bones, which are bevelled obliquely from below upwards, and so rounded off late-
rally that the contour of the two forms a large arc of a circle, the chord of which
measures 3-4 inches (Plate IV. fig. 1). The upper surface of each nasal bone is rough
and perforated by many vascular foramina, which open forward ; and the two nasal bones
are separated by a suture, which can be traced backwards in the middle line for 2'2 inches,
and then comes to an abrupt termination. I presume that the extent of this suture
indicates the distance to which the nasal bones reach backwards ; but there are no traces
of the nasofrontal, or nasomaxillary sutures. The middle of the under surface of each
nasal bone presents a strong, rounded, longitudinal ridge, on each side of which there is
an equally distinct concavity, and the apposed slightly thickened inner edges of the two
nasal bones form a third, less marked, median ridge. The expanded upper edge of the
perpendicular plate of the ethmoid embraces this middle ridge, while the nasal turbinal
bones are continuous with the ridges on each side of it (Plate VI. fig. 1).
A well-marked notch, or sinuosity, separates the upper from the lateral contour of
the anterior nares ; and, about an inch below this, the inner surface of the outer wall of
the nostril exhibits a rounded elevation or thickening. Still more inferiorly, the wall
of the nasal cavity is somewhat excavated, so as to present a thin anterior edge, which
passes into the trough-like lower boundary, constituted by the palatine portions of the
prsemaxillse. These are separated throughout their whole length in the middle line
(a distance of rather more than an inch) by a fissure less than one-tenth of an inch
in diameter posteriorly, but twice as wide in front, the prsemaxillse becoming more
PEOFESSOE HUXLEY ON THE OSTEOLOG-Y OF THE GENUS GLYPTODON. 45
distant by the divarication of their anterior and internal angles. The thick and rough
anterior edges of the preemaxillee diverge obliquely from one another, both forwards and
outwards and upwards and outwards, at a very obtuse angle, the interval between their
anterior and external terminations amounting to 1-5 inch (Plate IV. fig. 3). Viewed
laterally, the anterior ends of the nasal bones are seen to project about half an inch
beyond the upper part of the lateral boundary of the nares, which slopes upwards and
backwards with a slight forward concavity from the palatine portion of the preemaxilla
(Plate V. fig. 1).
The nasal cavity is divided, longitudinally, by a very strong osseous septum, which
extends to the posterior end of the premaxillary fissure below, and to within 0-4 inch of
the anterior contour of the nasal bones above (Plate VI. fig. 1). This septum terminates,
in front and below, in a thin jagged edge; but above, it expands into a broad plate
T2 inch wide, presenting a deep and broad notch above, into which, as I have previously
stated, the conjoined median edges of the nasal bones are received. The septum is about
2'6 inches high in front; and of this height 2-2 inches, or about five-sixths, is formed by
the perpendicular plate of the ethmoid, while the rest belongs to the vomer (Vo.). The
ethmoidal plate is thin in front, thicker in the middle, and thin again posteriorly. The
lower half is somewhat excavated on each side, from above downwards ; it ends in an
inferior edge, or rather surface, 0-7 inch in diameter, anchylosed with the upper edge of
the vomer, which has, in front, a corresponding thickness. The floor of the anterior
part of the nasal cavity (i. e. as far as the level of the fourth alveolus) is concave from
side to side, and convex from before backwards, its convexity corresponding with, but
being much more strongly marked than, the concavity of the arched roof of the palate.
At about 2 inches from the anterior boundary, a sharp longitudinal ridge commences
upon the floor of each division of the nasal cavity, and extends backwards, for a distance
of about 1| inch, to the summit of the arch formed by that floor (Plate VI. fig. 1, a).
Each ridge has a sloping convex external face, and a perpendicular concave inner face,
0-2 inch high. Between the latter and the side of the vomer, which is excavated for a
corresponding distance from above downwards, lies a canal, a quarter of an inch wide,
and open above and at its ends. The- floor of each nasal chamber rises gradually into
its lateral wall ; and upon this, about three-fourths of an inch from the floor, appears a
ridge which, at about an inch from the antero-lateral margin of the nostril (or just above
the anterior end of the ridge on its floor), passes backwards into the commencement of
the inferior spongy bone (Plate VI. fig. 1, b ). The root of attachment of this bone to
the maxilla is, as usual, a narrow and thin, though long, bony plate, which on its free,
or inner, side is continued into two scroll-like lamellae, an upper and a lower. The
upper scroll comes much further forward than the lower, and is a stout plate of bone,
slightly concave inwards and convex outwards. In front, it ends in a thin free edge.
Superiorly, its margin is folded over outwards, and becomes anchylosed with the lateral
wall of the nasal chamber.
The inferior lamella commences about an inch behind the superior one. It is thick,
46 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
convex inwards and concave outwards, and its inferior edge becomes much thickened as
it curves outwards. It is attached to the maxilla by an anterior and superior thin, and
a posterior and inferior, much thicker, plate of bone. Three passages, consequently, lie
between the lateral walls of the nasal chamber and the ‘ scrolls ’ of the inferior turbinal, —
an upper, long, narrow, and flattened from side to side ; a middle, reniform in section ;
and an inferior, rounded in contour. The ridges upon the under surfaces of the nasal
bones are continued, as I have stated above, into two thick plates of lamellated bone
(Plate VI. fig. 1, c), which increase in depth from before backwards and pass into what
are, probably, the superior ethmoidal turbinals. Their inner surfaces are flattened
and parallel with the sides of the perpendicular plate of the ethmoid. Their outer
surfaces, irregularly concave, are separated by but a narrow interval from the concave
faces of the superior scrolls of the inferior turbinal bone.
The posterior view of this fragmentary skull (Plate VI. fig. 2) affords a further insight
into the arrangement of the bones which contribute to the formation of the olfactory
chambers. The aspect presented is that of a transverse section taken just in front of the
anterior end of the cranial cavity. The comparatively thin posterior part of the lamina
jperpendicularis of the ethmoid (Fth) is seen abutting, above, against the frontal bones
(Fr), and, below, becoming connected with the vomer (Vo), the posterior nearly straight
free edge of which bone ends on the floor of the nostrils, at the level of the posterior
margin of the third molar tooth, and thence slopes obliquely upwards and backwards.
The ethmovomerine plate, however, is not free from all lateral' connexion with the tur-
binal bones, as is commonly the case ; but a thin plate of bone, convex forwards and
concave backwards, passes, on each side, from the vomer and the lamina perpendicularis
to the lateral masses of the ethmoid. The inner surfaces of these are marked by broad
flattened grooves, directed forwards and downwards, and separated by sharp ridges, which,
in the recent state, were probably produced into delicate plates of bone.
The lower portion of the lateral mass of the ethmoid, which represents the middle
turbinal, is continuous with the inferior turbinal. The upper portion, representing the
superior turbinal, is similarly continuous with the nasal turbinal. The superior tur-
binal of each side forms the floor of a considerable cavity (Plate VI. fig. 2), which is
walled in, externally and above, by the frontal bone, and represents a frontal sinus. A
rounded dome (a) of bone projects backwards from the anterior wall of this cavity,
which appears to communicate with the nasal fossse only by a few foramina, situated
around the margins of the dome.
The palate (Plate IV. fig. 3) is singularly narrow, seeing that its length, measured in
a straight line, is about 9^ inches, while its width, between the outer edges of the
alveoli, nowhere exceeds 3 inches. The longitudinal contour of the palate is concave
anteriorly, convex posteriorly (Plate V. fig. 1). The crown of the arch of the anterior
concave portion is opposite the hinder margin of the third alveolus ; from thence the
roof of the palate slopes, downwards and forwards, to the free premaxillary edge. From
the same point it slopes, downwards and backwards, to the level of the hinder margin
PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON. 47
of the fifth alveolus, while behind the sixth it ascends, somewhat abruptly, to its pos-
terior termination.
Throughout the posterior two-thirds of its length, the palate is slightly and evenly
concave from side to side ; but, from the third alveolus forwards, its middle part rises to
form a median convexity, which ends by a rough, abruptly truncated ridge (Plate IV.
fig. 3, a ), behind the premaxillary fissure. It forms, in fact, the posterior boundary of
a transverse fissure ending in a notch, or short canal, at each extremity, which represents
the anterior palatine foramen, and which, taken together with the intermaxillary fissure,
simulates very closely the form of a T. A deep groove (&) separates the raised part of
the palate from the alveolar margin, and ends, behind, in a canal which burrows into
the substance of the bone opposite the anterior edge of the third tooth on both sides.
On the left side, however, the hinder part of the groove is bridged over by a bar of bone.
Large foramina are situated, along a line continuing the groove, opposite the third and
fourth alveoli ; but no such apertures appear in the posterior part of the palate until
quite its hinder extremity is reached, when, on each side, two crescentic fossae (Plate IV.
fig. 3, c), wider in front than behind, lie on the inner side of the last alveolus, and appear
to separate the palatine from the maxillary bones. They end caecally above.
The bony palate exhibits no distinct sutures, except a trace of a maxillary suture
behind the anterior palatine foramen, and of a palatine suture, which widens behind
into a cleft, separating the arcuated, divergent inner and posterior boundaries of the
palatine bones. The free surfaces of the bony masses which bound the palate, poste-
riorly, are so smooth and unbroken, that I suspect the pterygoid bones must be repre-
sented in them.
As the palate presents very nearly the same width throughout, while the roof-bones
of the skull are always much wider than it, it follows that any vertical section of the
skull, perpendicular to its long axis, in the palatine region, would exhibit a trapezoidal
form, like that of the anterior nares — the predominance of the upper side over the lower
being still more marked. But in the antorbital region the roots of the zygomatic processes
are so large, and stand out so much from the sides of the head, that the skull, viewed in
front, looks almost like a cube, with its lower face produced forwards and downwards
into a truncated wedge (Plate VI. fig. 1). The only trace of a suture visible upon any
part of the sides of the facial wedge is an almost obliterated one (Plate V. fig. 1, a),
which runs from a slight notch, opposite the level of the anterior palatine foramen
and in front of the first alveolus, upwards and slightly backwards, and marks off the
ascending process of the prsemaxilla from the maxilla. This ascending process, very
narrow in the middle, widens above and joins the nasal bone, so that the circumference
of the anterior nares is completed by the prsemaxillse and nasal bones only.
Opposite the second and third alveoli, the maxillary bone, as I have stated; above,
widens out and expands into the root of a stout zygomatic arch, whence a process, nearly
6 inches long by 2 inches wide, passes directly downwards. The process is much flattened
from before backwards (Plate VI. fig. 1), and is arched from above downwards (Plate V.
mdccclxv. i
48 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
fig. 1), so as to be convex in front and concave behind. Its inner edge is thick and
rounded, except towards its termination, where it presents some slight irregularities or
cligitations. The outer edge is comparatively thin and rugose ; it is bevelled off inte-
riorly, and more obliquely on the right side than on the left. The inner part of the
front face of the process looks almost directly forwards, and is very smooth ; but the
outer part of that face looks outwards more than forwards, and is rugose (Plate YI.
fig. 1). The hinder, concave face of the process (Plate VI. fig. 2) is divided by an
oblique ridge (b), which passes from its superior and external to its inferior and internal
angle into two areee — an inner, smooth, and an outer, rough and tuberculated. The
superior and external part of the process, where it was doubtless continued into the
zygoma, is evidently fractured. The root of the zygoma is perforated near its origin by
a large, oval, infraorbital canal, the lower edge of which is rather more than an inch
distant from the lower margin of the root of the zygoma. The canal is short, and is
directed forwards and outwards.
The lachrymal foramen is a round aperture, placed upon the anterior edge of the orbit,
T6 inch above the infraorbital canal (Plate V. fig. 1, b).
The internal walls of eight alveoli, on each side, are preserved. The external walls
<of the anterior four upon the left side, and of the anterior three upon the right side,
•are almost entire ; but, posteriorly, the external walls of all the other alveoli, upon each
side, are broken away (Plate V. fig. 1).
Measured in a straight line, the eight alveoli occupy a space of 8 inches, and each
alveolus is, on an average, 0*9 inch long. The teeth which occupy the alveoli are sen-
sibly equal in long diameter ; but the anterior tooth is much narrower than the others,
measuring only 0‘35 inch in this direction, while the other teeth have a transverse
diameter of 06 inch, or nearly double that of the first.
None of the teeth are entire upon the right side. Of the left series, the crowns of
the first, third, fourth, and sixth are in very good condition, while the second is much
damaged ; of the fifth, only the middle lobe exists, and of the seventh only the two ante-
rior lobes (Plate IV. fig. 3).
The alveoli are exceedingly long, and the outer walls of the third and fourth, on each
side, are so much broken away, that the whole length of their alveoli can be observed
and measured. The fourth is 4*5 inches long, and bends outwards and forwards as it
passes upwards, to terminate nearly on a level with the lachrymal foramen. The tooth
which filled the alveolus must have had a corresponding length and curvature ; for the
two longitudinal ridges of bone, which partially subdivide the alveolus into three
chambers near its free end, are continued quite up to its closed extremity, and are
lined by a shell of dental substance, which gradually thickens below and becomes
continuous with the body of the tooth (Plate Y. fig. 1. 4, 4').
The third alveolus presents the same general curvatures as the fourth, but is inclined
somewhat further outwards at its upper end, which lies close to, and about an inch above,
the hinder end of the infraorbital foramen.
PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON. 49
The wall of the upper end of the first alveolus has been broken through on the right
side. It lies on a level with the upper edge of the infraorbital foramen, and imme-
diately behind the premaxillary suture.
From what remains of the hinder alveoli and teeth, I suspect they become more and
more nearly straight posteriorly.
The external vertical contour of each tooth must be very similar to that of the max-
illary surface between the upper end and the edge of the alveolus.
The lateral faces of all the teeth are divided by two longitudinal grooves, placed
opposite to one another on the two sides of each tooth, into three lobes.
In the first tooth these grooves are very shallow, so that the thickness of the tooth,
between the grooves, is far greater than the depth of a groove. In all the other teeth,
the thickness of the teeth between the grooves, or of the isthmus by which the lobes
of each tooth are connected, is much less than the depth of a groove.
The view of the palate (Plate IV. fig. 3) shows that lines following the planes of the
anterior surfaces of each of the four anterior teeth are directed inwards and forwards ;
while in the sixth and seventh teeth, if not in all four posterior ones, such lines are directed
inwards and backwards. The anterior surfaces of all the teeth, but the first, are concave,
the posterior surfaces convex. The grinding-surfaces of all the teeth are directed a little
outwards as well as downwards. Each surface is ridged in the middle and surrounded
by a thin raised margin, and the general arrangement of the ridges is such that one is
median, traversing the longitudinal axis of the grinding-surface, and three are disposed
at right angles to these, in the longitudinal axes of the three lobes. The transverse
ridges are continuous with the longitudinal, where they cut it (Plate V. figs. 3 & 4).
Sometimes a transverse ridge may be bifurcated at its extremity, or accessory branch-
lets may be given otf from the transverse, or from the longitudinal, ridges.
A large pulp-cavity occupies the upper portion of each tooth ; but as its walls begin
sensibly to thicken at about the junction of the upper and middle thirds of the tooth,
the pulp-cavity diminishes in a corresponding ratio, and, rather below the middle of the
tooth, it becomes obliterated.
The Mandible* . — The lower jaw of Glyptodon is very remarkable, partly on account
of the trough-like projection of the symphysis, but more especially by reason of its great
height in relation to its length. The height, as measured from any horizontal surface on
which the jaw is allowed to rest, to the summit of the articular condyle, is 9’25 inches;
* Leaving aside for the present M. Nodot’s “ Schistopleuron,” the only fragment of the lower jaw of Glyp-
todon clavipes yet described is that mentioned in the Catalogue of the Royal College of Surgeons under
“ No. 517. A fragment of the anterior part of the left ramus of the lower jaw, including portions of the
sockets of the anterior teeth. The first is small and simple, and is situated close to the anterior termination of
the dental canal ; the second socket shows, by the two prominent vertical ridges on its anterior and posterior walls,
that the tooth which it contained had the fluted form characteristic of the genus ; the third socket, which is the
most complete, differs from the preceding in a slight increase of size, and it shows that the tooth was implanted
by an undivided base of considerable length, and of the same size and form as the exposed part or crown.”
i 2
50 PEOFESSOE HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
while the length, measured in a straight line, from the symphysis to the angle of the
jaw, is not more than 10 ‘75 inches. The horizontal ramus is very deep and thick, mea-
suring about 3-25 inches vertically by 1-5 inch in thickness, while the ascending ramus
is 3'5 inches wide by about 09 inch thick at thickest (Plate V. fig. 2).
The anterior end of the mandible is 2*9 inches wide and abruptly truncated, ending in
a rugose edge, nowhere more than half an inch thick, which, at its extremities, bends
round at a right angle into the upper margins of the rami (Plate VI. fig. 5). These,
thick and rounded, ascend somewhat towards the first alveolus, which is 2-25 inches
distant from the anterior end of the ramus. The symphysis, 5 '7 inches long, appears
to be formed, by the sutural union, and not by the anchylosis of the rami ; but the bone
has been so broken that a large aperture occupies the middle of the symphysial space
(Plate VI. figs. 4 & 5).
The exit of the inframaxillary canal is nearly half an inch wide, and is situated If-
inch below the upper margin of the jaw, and directly beneath the anterior boundary of
the first alveolus. The anterior, or symphysial, contour of the mandible slopes, with a
slight forward concavity, obliquely downwards and backwards to the level of the foramen ;
and is then continued, almost straight, or with a slight anterior convexity, to a point
nearly in the same vertical line as the hinder edge of the third alveolus (Plate V. fig. 2).
The symphysial face is convex from side to side inferiorly, and gradually widens
until, at its hinder end, its breadth amounts to 5 "5 inches. Its outer boundary is
formed by an obtuse longitudinal convexity, which runs along the middle of the outer
face of the horizontal ramus, and dies away, posteriorly, at the commencement of the
ascending ramus. From this ridge, or convexity, the summit of which corresponds with
the greatest outside breadth of the jaw, the outer surface of the ramus slopes upwards
and inwards to its alveolar margin (Plate VI. fig. 4). The inner face of each horizontal
ramus is slightly concave from above downwards, passing, in front, into the excavated
upper surface of the symphysis.
The general contour of the anterior half of the alveolar margin of the mandible is
slightly convex upwards, in correspondence with the concavity of the opposed region of
the maxilla (Plate V. fig. 2). The posterior half of the same margin is broken away ;
but it may be assumed that it was concave upwards, answering to the downward con-
vexity of the hinder part of the maxillary alveolar edge.
The inner edges of the alveolar margins of the two rami are 2 inches apart. In the
left ramus the series of alveoli is tolerably well preserved for 5^ inches, or to a point
behind the anterior edge of the ascending ramus. From the character of the broken
surface behind this point, however, it is obvious that the series of alveoli was continued
along the inner surface of the ascending ramus, very nearly to the angle of the jaw, and
considerably behind a line let fall perpendicularly from the articular condyle — an arrange-
ment which, so far as I am aware, has no parallel among Mammalia (Plate VI. fig. 5).
As the whole length of the series of mandibular alveoli is about 8 inches, it is pro-
bable that the number of teeth was the same below as above, or eight on each side.
PROFESSOR HUXLEY OX THE OSTEOLOGY OE THE GENUS GLYPTODON. 51
The external surface of the perpendicular ramus of the mandible is rugose, slightly
convex from above downwards and from side to side, while its internal surface exhibits
a corresponding concavity, which is exaggerated below by the inward projection of the
posterior alveoli, and is divided by an elevation of its surface, which ascends obliquely
from the alveolar margin towards the coronoid process, into an anterior and a posterior
moiety. The apex of the coronoid process is broken away upon each side, but it seems
not to have extended beyond the level of the articular condyle, from which it is sepa-
rated by only a shallow notch.
The hinder margin of the perpendicular ramus, which is very thin inferiorly, thickens
•with the rest of the bone superiorly, and ends above in a transversely elongated condyle,
which projects further upon the inner than on the outer side of the plane of the ramus
(Plate V. fig. 2°). Viewed laterally, this condyle has the form of a wedge, the base
of which is O’ 7 inch broad; its hinder face being slightly concave, while its anterior
face, convex from above downwards, and slightly concave from side to side, looks
forwards and upwards (Plate V. fig. 2). It is this face which bears the surface for
articulation with the squamosal element of the skull, and is indeed coextensive there-
with. The surface in question is 1*25 inch wide from side to side, and 06 inch broad
or from above downwards, and is tolerably smooth, but not very different from the
adjacent parts of the condyloid process.
The remains of five successive anterior teeth are observable in the alveoli of the left
ramus of the mandible, and the socket of the sixth is clearly defined. Behind it, for a
space of 1'8 inch, the inner wall of the ramus is broken away so completely that no trace
of any alveolus is left. On the right side, the bone is nearly in the same state, but at .a
distance of 7'6 inches from the anterior edge of the most anterior alveolus, I observe a
smooth vertically grooved surface of bone, which is situated nearly in the same plane as
the outer walls of the other alveoli, and which I conceive to be part of the outer wall of
the last alveolus.
The teeth of the mandible present the same trilobed form and other general charac-
ters of those of the maxilla, but very few are in a sufficiently entire state to furnish
materials for description. The first and second, on the left side, and the third, upon the
right side, however, have their grinding-surfaces entire, or nearly so (Plate VI. fig. 5).
The grinding-surface of the first tooth (left side) is 085 inch long and 04 inch wide
at- widest. It has a very different form from the first tooth of the maxilla, the two
posterior ridges of the outer surface being much more developed.
The grinding-surface of the second tooth (left side) measures 09 inch by 045 inch;
its outer ridges and grooves are also the better marked. The posterior surface of the
tooth is fiat or a little concave, and its plane is directed obliquely outwards and back-
wards.
The grinding-surface of the third tooth (right side) is l-05 long, and the isthmuses
which unite its prisms are much narrower than in the second tooth. Both the anterior
and the posterior faces of the tooth are curved. The grinding-faces of all these teeth
52 PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON.
are inclined a little inwards as well as upwards, reversing the direction of the grinding-
faces of the upper teeth.
The mandibular teeth seem to have been nearly straight, without either external or
internal concavity. Their long axes are inclined rather backwards as well as downwards.
The alveolus of the fourth tooth, on the right side, is laid open ; and I judge from it
that the fourth tooth must have had a length of about 3^ inches ; and the others might
have had the same dimensions, except the first, which is certainly shorter, probably not
exceeding 2^ inches.
A considerable canal traverses the right ascending ramus from behind and below, up-
wards, forwards, and outwards. Its external aperture, oval, 0*3 inch wide, lies upon
the outer face of the ramus, on a level with the alveolar margin, and rather nearer its
anterior than its posterior edge (Plate V. fig. 2). The inner end of the canal, which is
T7 inch long, terminates in the broken cancellous structure, on the outer side of what
appears to be the remains of the last alveolus.
I cannot certainly discern any remains of a corresponding canal in the left ascending
ramus.
All that remains to be described in this skull is a fragment of the basis cranii, con-
sisting of part of the anchylosed basi- and pre-sphenoid bones. The presphenoid (Plate
VI. fig. 2) is remarkable for the strong crest or spine into which the middle of its upper
surface is produced, and which was not improbably continued into an ethmoidal crista
galli. The posterior apertures of the passages for the optic nerves are ellipses, with their
long axes directed upwards and outwards ; they are about a quarter of an inch in dia-
meter, and are continued into two canals, which are traceable, outwards and upwards,
for about an inch in the substance of the orbitosphenoids. On each side, below and
external to the optic foramina, are strong grooves which formed the inner portion of the
confluent foramen rotundum and sphenorbital fissure. The front face of the presphenoid
and the roots of the orbitosphenoids are excavated by deep sphenoidal sinuses.
Comparison of the Skull of the present specimen with that of the typical Glyptodon
clavipes. — The principal parts which exist in both skulls, and may therefore serve as
terms of comparison, are, 1, the nasofrontal region of the roof of the skull; 2, the
descending zygomatic processes ; 3, the alveoli ; and 4, the basi- and pre-sphenoid.
1. The resemblances in size and general configuration between the nasofrontal regions
of the two skulls are so obvious that I need hardly dwell upon them at any length.
The present specimen differs from the type in the more rounded contour of the nasal
bones, in the persistence of the nasal suture, in the less rugosity and squareness of the
supraorbital prominences, and in the far less marked definition of the temporal ridges ;
but none of these characters appear to me to have more than an individual import-
ance, and I am inclined to suspect that they depend largely on the less advanced age
of the present specimen.
2. The zygomatic processes have the same length (measured from the infraorbital fora-
men) in each case. They are slightly narrower in the type specimen ; in other respects
PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON. 53
the zygomatic processes of the two specimens do not differ more than those of opposite
sides in the same specimen.
3. In the typical specimen the upper ends of the three anterior alveoli, on each side,
are preserved; they occupy just the same space as the three anterior alveoli of the
present specimen.
4. The presphenoid in the type has the same crest, and the inner ends of the optic
foramina are precisely the same distance apart.
When to these correspondences we add that the distance from the front edge of the
nasals to the level of the posterior edges of the supraorbital prominences is the same in
both skulls, and that the lower jaw of the new specimen would fit very fairly on to the
typical skull, it will, I think, be admitted that there is sufficient evidence of the specific
identity of the animals to which the two skulls belonged, and that the imperfections
of the new specimen may be supplemented by the evidence afforded by the typical
example.
Further data as to the Cranial Structure of Glyptodon furnished by the typical skull.
— Professor Owen (‘ Catalogue of Fossil Mammalia and Aves,’ p. 384) thus describes
the fragmentary skull of the typical specimen of Glyptodon clavipes : —
“ The occipital condyle (a) presents a convexity in the vertical direction, which
describes more than a semicircle, and is slightly convex transversely, but is narrower in
that direction than it is in the Mylodon : it is directed in the Glyptodon backwards and
obliquely outwards. The occipital foramen (b) is very large and transversely elliptical ;
its plane is inclined from below upwards and backwards 20° beyond the vertical line.
The anterior condyloid foramen (c), though large, is relatively smaller than in the Mylo-
don, and is situated close to the anterior border of the condyle. The depression for
the digastric muscle ( d ) is perforated and separated from the condyle by a wider tract
of the paroccipital (e) than in the Mylodon ; and the petromastoid ( f ) below the digas-
tric depression presents a rough convexity, bounded posteriorly by a transverse ridge of
the paroccipital instead of the hemispherical depression for the articulation of the stylo-
hyoid bone which characterizes the skull of the Mylodon . The basioccipital ( g) pre-
sents a median smooth concavity and two lateral rough depressions, which are continued
on to the basisphenoid (A), and indicate the insertion of very powerful ‘ recti-capitis
antici majores’; the obliterated suture between the basioccipital and basisphenoid forms
a rough transverse ridge. The inequalities of this part of the basal region of the skull
present a striking contrast to the broad smooth and even tract which the same part
forms in the Mylodon. The sides of the concave under surface of the basisphenoid are
bounded by longitudinal ridges, which have been broken off in the specimen. The
petrous bone terminates by a prismatic pointed process in the foramen lacerum (i),
which here gives passage both to the jugular vein and internal carotid. The foramen
ovale (k) is circular, and of the same size as the anterior condyloid foramen. The fora-
men rotundum (l) is one inch and a half in advance of the foramen ovale, and opens
with the commencement of a deep and long groove, which traverses the base of the
54 PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON.
pterygoid processes in the direction towards the antorbital foramen. The base of the
zygomatic process supporting the articulation of the lower jaw (m) is brought much
nearer the occiput than in the Mylodon , and is separated from the petromastoid by a
deep excavation, perforated by wide apertures that seem to communicate with the tym-
panic cavity. The articular surface for the lower jaw is well defined, narrow in the axis
of the skull, much extended transversely, gently convex in both directions. In the
skull of a recent Armadillo ( Dasypus octocinctus ) the articulation for the lower jaw is
almost flat, and on a level with the roof of the posterior perforated cavity. In the Prio-
nodon {Dasypus gig as, Cuv.) the articular surface is slightly concave, and extends longi-
tudinally forwards from the posterior cavity. The zygomatic process of the malar bone,
bounds the outer and fore part of the surface, and extends forwards in the form of a
laterally compressed plate of bone, and in the Das. sexcinctus forms a slight angular
projection below the antorbital perforation. In the Glyptodon , the articulation for the
lower jaw more resembles that in ordinary Pachyderms, and is thus conformable with
the deviation from the Edentate structure manifested by the bones of the foot. But
the most remarkable characteristic of the skull of the Glyptodon , by which it differs
from the existing Armadillos and approaches the Megatherioids, is the long and strong
process (n) which descends from the base or origin of the zygomatic process of the maxillary
bone. This process is compressed, but in the opposite direction to that in the Mylo-
don., viz. from before backwards, instead of from side to side ; it measures five inches in
length from the antorbital perforation, one inch and three-fourths in breadth across the
middle : the outer margin is entire, and as if folded back ; the lower half of the inner
margin is slightly notched, the extremity of the process curves backwards. Both ante-
rior and posterior surfaces bear strong marks of the attachment of muscular fibres.
“ The small remaining portion of the maxillary bone- on the inner side of this process
shows portions of three deep sockets (o o ) of the same diameter throughout, indicating the
implantation of molar teeth by a single excavated base, and showing two longitudinal
ridges on both the outer and the inner side, which proves the teeth to have had the
same fluted exterior which they present in the lower jaw, and of which the generic
name of Glyptodon is expressive. The fractured anterior part of the basis cranii shows
the large cavities for the olfactory bulbs, and the remains of a very extensive cribriform
plate, the organ of smell being very largely developed.
“ The posterior, or occipital surface of the skull slopes forward from the plane of the
occipital foramen at an angle of 45° ; in the small existing Armadillos it is vertical ; in
the Glyptodon it is divided by a strong median vertical ridge, and separated by a sinuous
thicker transverse ridge from the upper surface of the skull. The posterior half of this
region of the cranium is marked by the ridges bounding the origins of the temporal
muscles, which almost meet along the middle or sagittal line. Part of the lambdoidal
suture is seen at p ; the other cranial sutures are obliterated. The temporal fossae are
pierced by numerous large vascular foramina. The anterior parts of the temporal
ridges (g) diverge to the posterior angle of the supraorbital ridges. The frontal or inter-
PROFESSOR HUXLEY ON THE OSTEOLOG-Y OF THE GENUS GLYPTODON. 55
orbital part of the upper surface of the cranium is broad and nearly flat, smooth, and
slightly concave at its posterior half, slightly convex, rough, and perforated by vascular
foramina at its anterior half. The most prominent parts above the orbits are most
rugose, and indicate a more intimate adhesion to the superincumbent osseous dermal
helmet. The lachrymal foramen (r) is pierced immediately in front of the anterior
border of the orbit.
“ The difference in the development of the temporal muscles manifested by the Glypj-
todon and Mylodon in the position of the ridges in the fossil cranium indicates a corre-
sponding difference in the power of mastication and in the density of the alimentary
substances habitually selected by each species ; the greater proportion of hard dentine
in the teeth of the Glyptodon , and the greater number of the teeth, which appear to
have been thirty-two, eight on each side of both jaws, coincide with the characters of
the cranium, and support the inferences thence deducible.”
It is necessary to make certain additions and qualifications to the above description.
If we may be guided in the interpretation of the structure of the auditory region by
the analogy of the existing Euphractus , the part which is there termed “ paroccipital”
(Plate IV. fig. 5, h) includes the true mastoid; the “perforated depression for the
digastric muscle ” (Plate IV. fig. 5,f) is the external auditory meatus; and that which
is termed “ petromastoid below the digastric depression ” (Plate IV. fig. 5, g) is part of
the tympanic element of the temporal bone. It would appear that, as in Euphractus,
the tympanic bone sends a process outwards and backwards, the extremity of which
comes into contact with the pars mastoidea, and so bounds the external auditory meatus
externally and below ; while it leaves between itself, the proper tympanic bulla, and the
pars mastoidea, an aperture which communicates with the external auditory meatus.
The latter is remarkably small for so large an animal. The “ bulla,” into which it
opened, is broken away ; but it is probable that a considerable part, if not the whole,
of the rugose spaces supposed above to be for the insertion of “recti capitis antici,”
mark the place where the thick inner walls of the bullae impinged upon the basioccipital.
The fenestra rotunda is visible upon the under surface of the pars petrosa as an oval
aperture 0T5 inch wide, the long axis of which is directed almost transversely to that
of the skull. The fenestra ovalis , smaller, appears above the fenestra rotunda. The
proper carotid canal probably traversed the anterior part of the internal wall of the bulla
as in the Armadillos; the jugular vein most likely left the skull by a passage between
the posterior and internal part of the bulla, the exoccipital, and the periotic.
The large apertures perforating the roof of the cavity which is situated behind the
articular facet for the lower jaw, do not communicate with the tympanic chamber.
They are probably venous channels, and they communicate internally with the cavity of
the skull.
The articular facet for the lower jaw measures 1*8 inch along its greater, and 0-6 inch
along its lesser diameter ; its edges are well defined, and it has a somewhat kidney-shape,
the hilus of the kidney being turned downwards (Plate IV. figs. 4 & 5, e). The’general
mdccclxv. K
56 PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON.
aspect of the facet is backwards and downwards, so that, when viewed laterally, its
plane appears inclined more than 45° to a horizontal line. The long axis of the facet
is nearly at right angles to the axis of the skull, but its outer half has a slight inclination
forwards and outwards. It will be observed that the direction of this facet corresponds
very well with that of the articular facet on the condyle of the lower jaw of the new
specimen ; and the nature of the articulation is such that the lower jaw must have had
a purely hinge-like movement in a vertical plane, the doubly curved upper surface
of each row of mandibular teeth being brought, with a simply crushing motion,
against the correspondingly curved lower surface of the maxillary teeth in each masti-
catory act.
The “ deep and long groove ” into which, in the above description, the foramen rotun-
dum is said to enter, requires particular notice. The foramen rotundum and the spheno-
orbital fissure are represented by a rounded aperture 05 inch wide, situated immediately
in front and to the inner side of the foramen ovale , and separated from it by only a
narrow bar of bone. The small optic foramen, in like manner, lies immediately in front
and to the inner side of this aperture, separated from it only by the lower root of the
orbitosphenoid.
The alisphenoid is prolonged forwards as a broad plate, parallel with the orbitosphe-
noid, for about an inch ; and thus the conj oined foramen rotundum and Jissura spheno -
orbitalis are continued outwards and forwards by a wide canal of the same length. Ante-
riorly, the alisphenoid ends in an arcuated free edge, and so forms the hinder part of
the outer lip of a groove open inferiorly, the inner wall of which is constituted by the
lateral mass of the ethmoid. The front part of the outer lip of the groove, separated
from the other by a slight interval, is formed by a strong descending vertical plate of
the frontal bone, ending below in a rugose edge, thicker behind than in front, which
sweeps upwards and forwards towards the posterior part of the infraorbital prominence.
It ceases at about three-quarters of an inch from that part.
The optic foramina are prolonged into canals directed forwards and outwards, each
about an inch long, the anterior apertures of which open on the inner wall of the great
passage just described, immediately behind the level of the anterior edges of the alisphe-
noids.
The optic nerves, which could hardly have been more than OT inch in diameter, and
were therefore very slender in relation to the size of the animal, must have been con-
tinued forwards between the frontal plate and the ethmoid for a distance of at least
3^ inches before they reached the eyeball.
Three other apertures are visible in the roof of the groove — one, about as large as the
optic foramen, on its outer side, and three-quarters of an inch in front of the proper ante-
rior end of the optic canal. The two others are smaller and situated close together, and
rather on the inner side, half an inch in front of the former. These may be the ends of
canals for the oculomotor nerves.
The» remains of the expanded upper edge of a lamina perpendicularis, similar to that
PROFESSOR HUXLEY ON THE OSTEOLOGY OE THE GENUS GLYPTODON. 57
described in the new specimen, are visible, attached to the under surfaces of the nasal
bones.
The inner surface of the right lateral portion of the ethmoid is marked by obliquely
diverging ridges of bone, with which the plates of the inferior spongy bone were doubt-
less connected.
By combining the new specimen with this it is easy to ascertain approximatively the
length of the cribriform plate. The former specimen, in fact, is broken through at a
distance of six inches from the anterior end of the snout, but its posterior face does not
exhibit any notable part of the anterior wall of the cranial cavity. The same distance
(6 inches), therefore, measured off upon the roof of the type skull, should give the
position of a line beyond which the cribriform plate certainly did not extend anteriorly.
From the point thus defined to the anterior edge of the presphenoid is a distance of
1*75 inch, which must therefore represent the maximum length which the cribriform
plate could have attained. The distance from the anterior edge of the presphenoid to
the level of the posterior margins of the occipital condyles is 4*5 inches. The cribriform
plate is rather shorter in proportion to the base of the skull in the Glyptodon than in
the ordinary Armadillos, and its anterior part is situated far further back in relation to
the antorbital processes.
The proper cranial cavity, or brain-case, is small when compared with the whole size
of the skull, if the chambers which lodge the olfactory bulbs are left out of considera-
tion. It is in fact only 4*5 inches long, 2*5 inches wide at widest, and about If inch
high at highest. Its greatest width is situated beneath the occipital ridge, whence it
narrows towards the olfactory outlet, which is about 1*25 inch wide. The immediate
side walls and roof of the fore part of the cranial cavity are formed by a very thin inner
table of bone, separated by a wide air-chamber from the denser and stouter outer table.
This air-chamber does not appear to extend back beyond a transverse line connecting
the two glenoidal facets.
Mr. Flower has obtained a cast of the cranial cavity, from which one is enabled to
form an idea of the shape and size of the brain. The proportionally large cerebellum
exhibits a prominent vermiform process, and is completely uncovered above by the
cerebral hemispheres. The latter are quite smooth, and their upper contour is much
arched, while their sides are flattened, and approach one another anteriorly. The
absence of convolutions in the brain of so large an animal, together with the small
absolute mass of the organ, leads one to suspect a great absence of intelligence in the
Glyptodon.
k 2
58 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
Measurements of the Skulls.
A. The new specimen. inches.
Total length of the palate in a straight line 9*50
Width between the inner edges of the alveolar series T75
Width between the outer edges of the alveolar series, opposite third tooth 2*95
„ 5j „ „ last tooth . 2*8
„ „ „ „ first tooth . 2*6
Hinder edge of the last alveolus in front of the posterior nares . . . 0-5
Outer edge of the malar process to the centre of the palate . . . . 5’5
The extreme breadth of the skull therefore = 11*0
Vertical height of skull from frontal bones to palate at fourth tooth . . 6*0
From end of outer edge of orbit to the same point on the opposite side . 7*2
Summit of the frontal region to the ends of the malar processes . . . 9-5
Mandible : —
Extreme length from the symphysis to the angle 10*7
Extreme height from the summit of a condyle to a flat surface on which
the jaw rests 9*3
Depth of the horizontal ramus at the third tooth 3*2
Width at the symphysis 2*9
Width between the inner edges of the alveoli opposite the first tooth
# (remains the same throughout) 3*1
Width between the outer edges at the same point 31
Width between the outer edges at the third tooth 3*25
B. The type specimen.
Extreme length from nasal bones to the level of the occipital condyles . 12*7
„ „ „ superior occipital ridge . . . 105
Breadth at the front part of the orbits 6*8
„ at the interorbital constriction 4*3
„ across the occiput, about 5*8
Height of the occiput . 2-6
Distance between the inner edges of the articular surfaces for the
condyles of lower jaw 4*25
§ 2. The Vertebral Column.
The remains of this very interesting part of the organization of Glyptodon are, unfor
tunately, in a somewhat imperfect state, though enough exists to demonstrate its alto-
gether unique character.
PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON. 59
The Atlas. — Of this bone the mutilated right half is represented in Plate VII. fig. 1,
giving the anterior, and fig. 2 the posterior aspect of the fragment.
The specimen exhibits rather more than the right half of the lower arch, and rather
less than the corresponding portion of the upper arch of the bone. The right lateral
mass, with its anterior and posterior articular facets, is almost entire, but the transverse
process is broken off close to its origin. The inferior arch is a solid bar of bone with a
straight upper and a convex lower contour ; and somewhat thicker in the middle, both
from above downwards and from before backwards, than at the sides. A section taken
through the median plane of this part of the bone would have the shape of a spherical
triangle; the lower or horizontal face convex, the anterior slightly concave, and the
posterior and upper also concave.
The middle of the posterior and upper face of the inferior arch presents an oval arti-
cular facet (fig. 2, a) for the odontoid process of the axis, which, when entire, must have
measured about 1-6 inch in width by 0-8 inch in antero-posterior length. It is slightly
concave, both from before backwards and from side to side, and is bounded by a well-
defined though narrow ridge. The outer end of this facet is half an inch distant from
the inner and lower edge of the articular surface for the odontoid vertebra, upon the
lateral mass of the atlas (fig. 2, b). This is a reniform surface with its inner and anterior
side concave, while the outer and posterior aspect is convex. Its long axis is almost
vertical, while the plane of its surface, which is a little concave both from above down-
wards and from side to side, is directed obliquely inwards and forwards. Lines drawn
through the shorter axes of the two articular facets would intersect one another at a
point very slightly in front of the anterior margin of the inferior arch. The foramen
for the vertebral artery is situated on the outer side of the facet, opposite the junction
of its middle and upper thirds, and nearly on the same level as a tubercle for the trans-
verse ligament, situated on the inner side.
The foramen (fig. 2, c ) leads into a canal which passes directly forwards, widening
as it goes, and traverses the root of the transverse process. In front of this it presents
a large oblique aperture, by which, however, it does not terminate. Instead of ending,
it makes an abrupt turn upwards through the substance of the superior arch of the atlas,
parallel with, and equidistant from, the anterior and posterior margins of that part, and
ends by an oblique aperture in the outer part of the roof of the cavity of the atlas, and
nearer the occipital than the odontoid edge. The upper face of the lateral mass of the
atlas presents an elongated, irregular, transverse aperture, which communicates with the
canal, and from the anterior and posterior margins of which broad and shallow grooves
are continued.
The articular surface for the occipital condyle upon the anterior face of the lateral mass
of the atlas (fig. 1) is much more concave from above downwards than that just described ;
and as it is neither concave nor convex from side to side, the surface may be regarded
as a segment of a hollow cylinder, answering to rather less than half the circumference
of such a figure. When the inferior arch of this atlas is made horizontal, this articular
60 PROFESSOR HUXLEY ON THE OSTEOLOG-Y OF THE GENUS GLYPTODON.
surface looks forwards and inwards. The inner and lower edges of the opposite occi-
pital facets of the atlas must have been separated by a distance of about 1*9 inch.
The transverse process of the atlas is, as I have stated, broken off close to its origin ;
but the cancellated fractured surface, 2 niches long by more than half an inch wide
superiorly, proves that the process was flattened from before backwards, and that it
arose from the posterior half of the outer surface of the lateral mass of the bone. The
surface of attachment of the process is almost perpendicular to that of the axis of the
spinal canal, or, at most, has a very slight inclination from above downwards and for-
wards. The general plane of the process, on the other hand, as exhibited by an upper
or an under view, is directed backwards and outwards. There are no means of judging
how far the process may have extended outwards.
The Odontoid and immediately-following Cervical Vertebrae. — The fragment of this
region of the vertebral column (figured in Plate IX. fig. 5 from without, fig. 6 from
within, fig. 7 from behind, and fig. 8 from below) is composed of the right half of the
neural arch of the axis, or odontoid, vertebra, anchylosed together with the arches of the
third and fourth cervical vertebrae. It formed the right half of the roof and side walls
of the neural canal in this region. The front face of the bone, thick and prismatic, is
obliquely bevelled off to a rounded edge, which is concave anteriorly. The outer face is
produced above into a tuberosity, the anterior part of which is perforated by a canal
which traverses the whole thickness of the bone and opens on its inner face, near its
upper end (fig. 5, c , fig. 6, c1). From the tuberosity a small ridge, partly broken away,
leads forwards and inwards along the anterior face of the bone. A stouter ridge extends
inwards near the posterior margin of the bone, from the same tuberosity. These two
ridges were situated upon the proper upper surface of the arch, and probably joined the
anchylosed spinous processes.
The lower part of the outer face presents a broken surface, with the outer termina-
tions of three canals (figs. 5 & 8, d, e,f), the inner ends of which are visible on the inner
or under surface of the bone (fig. 6, d, e,f) as they traverse its thickness obliquely from
within outwards and downwards. The hindermost of these canals (d) is wide below, but
narrows into a fissure above. The second, or middle, foramen (e) is wider, oval, and looks
more downwards. The third (f) is much smaller than either of the other two. On the
inner face of the bone (fig. 6) the aperture of the posterior canal ( d ) is longest. The middle
canal opens upon nearly the same level ; but the third, or anterior, canal takes a much
shorter course through the bone, and thus its inner end is on a level below the others.
The aperture of the middle canal is situated at about the same distance from the ante-
rior margin of the bone as the inner end of that canal ( c , c') which, I have stated, opens
externally upon the tuberosity. A little aperture (g) in the same line with these two
leads into the substance of the bone, and seems to have no external outlet. Lines drawn
through the three apertures referred to, mark off an anterior segment of the bone from
a middle segment, which is defined, by a line drawn from the inner end of the posterior
canal below to another small aperture ( h ) above, from a hinder segment.
PROFESSOR HUXLEY OX THE OSTEOLOGY OF THE GENUS GLYPTODON. 61
The posterior face of the bone exhibits, below, a large round aperture (fig. 7, a),
leading into a passage which traverses the posterior canal just described, and debouches
into the middle one.
Immediately beneath this foramen is a small concave articular surface, apparently a
fragment of a much larger one.
Superiorly and internally the posterior face of the bone presents a deep fossa (fig. 7, a),
bounded above and internally by a concave articular facet, the long axis of which is
directed almost at right angles to the long axis of the bone.
The facet in question I take to correspond with the posterior oblique process or
“ post-zygapophysis ” of the fourth cervical vertebra. The foramen on the posterior
face is the aperture of the canal for the vertebral artery. The facet below it is part of
an articular surface upon the inferior or “ capitular ” division of the transverse process,
which is characteristic of the cervical vertebrae in Armadillos; and the middle and poste-
rior canals are the intervertebral foramina for the third and fourth cervical nerves.
The upper and inner foramina and canals represent the remains of the primitive inter-
spaces between the several arches. The anchylosed spinous processes, and the bodies of
the three coalesced vertebrae, are completely broken away, so that nothing can be said
regarding their characters.
The fifth and sixth Cervical Vertebrae. — No remains of the fifth and sixth cervical ver-
tebrae have been discovered among the bones sent by Sehor Terrero.
The “ Trivertebral bone” or anchylosed seventh Cervical and first and second Dorsal Ver-
tebrae (Plate VII. figs. 3, 4, 5, 6). — The three vertebrae which enter into the composition
of this singular bone are very much depressed from above downwards, so that the neural
canal is more than twice as wide as it is high ; while the greatest depth of the whole
bone, leaving the spinous process out of consideration, is hardly a fourth of its width.
The inferior face of the bone is deeply concave from side to side ; and as the floor of the
neural canal is also concave, the part which corresponds with the centra of the anchylosed
vertebrae has the form of a broad thin arched plate, thinnest in the middle. The supe-
rior arches of the vertebrae, which constitute the roof of the trivertebral bone, follow, in
a general way, the contour of its floor ; but they are much thicker ; and, posteriorly, the
roof of the trivertebral bone is produced, upwards and backwards, into a very thick
short process, which probably represents the spinous processes of the two anterior dorsal
vertebrae. The lateral parts of the trivertebral bone, which represent the anchylosed
transverse processes of the vertebrae, are very thick and stout, especially in front.
Viewed from above, or laterally, they are seen to be marked out by excavations into
three portions, one for each primitive vertebral constituent of the bone. With the
lateral excavations the heads of the two anterior ribs articulate.
So much for the general characters of this bone. A front view (Plate VII. fig. 5)
exhibits the following features, worthy of more particular description. The lateral
mass, which represents the transverse process of the first of the three vertebrae, presents
an elongated oval articular facet (a), convex from above downwards and looking almost
62 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
directly forwards, its long axis being horizontal and at right angles to the axis of the
spinal canal. The facet is 1*8 inch long by 09 inch maximum height.
This articular facet is separated by a deep groove, into the bottom of which a large
canal ( d ) opens, from two other articular surfaces (b, c ), placed one immediately above
the other, and also parted by a deep channel, which may be regarded as an internal
branch of the groove.
The lower articular face (c), almost flat, looks inwards and forwards ; and its long axis,
which continues the direction of the floor of the neural canal, is inclined from above
downwards and outwards.
The upper facet (b), also flat, and, elongated transversely, looks directly upwards. Its
inner end is nearer the lower facet than its outer end ; and a well-marked fossa or
depression lies behind it. The upper articular surface certainly answers to the anterior
oblique process or “ prezygapophysis ” of the seventh cervical vertebra. The nature of
the lower and of the outer facet will only become obvious when the characters of the
cervical vertebrae of recent Armadillos have been explained. The anterior face of the
spinous process of the trivertebral bone exhibits two ridges, each convex towards the
middle line, which divide the face into a middle and two lateral areae.
The upper face of the bone (Plate VII. fig. 3) presents three pairs of foramina, termi-
nating internally in canals which lead into the spinal canal, and externally opening into
recurved grooves on the surface of the bone. The middle apertures are the largest, and
the corresponding grooves more strongly defined and wider. The posterior apertures
are smallest, and are situated quite close to the hinder margin. The surface of the bone
between these apertures is rough and irregular. The margins of this face of the bone
are produced into three processes which alternate with the foramina. The hindermost
of these processes is the largest, and ends in a point which is somewhat recurved and
bent down.
A side view of the trivertebral bone (Plate VII. fig. 6) shows that these processes are
continued into irregular vertical ridges, between which two fossae are enclosed. Of
these, the anterior is much deeper and more capacious than the other. It is an irre-
gular cavity subdivided by a vertical ridge into two, each of which presents a somewhat
deeper fossa at its inner and lower end.
The second, shallower, fossa, which lies between the hinder face of the middle process
and the front face of the posterior process, presents an elongated irregular articular
facet on its anterior wall, and a more rounded articular surface on its posterior wall.
The second rib is received into this fossa, and articulates with both these facets.
The posterior face of the third process presents a small, slightly concave, oval arti-
cular face on its lower half, with which the third rib was doubtless connected.
The posterior aspect of the trivertebral bone (Plate VII. fig. 4) presents for notice,
besides the features already mentioned, several others. The neural arch of the hindermost
vertebra of the three overhangs ; and its under face exhibits two oval slightly concave
articular faces (a, a), the posterior oblique, or “ postzygapophysial,” surfaces of the
PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON. 63
second dorsal vertebra. These, however, are not carried upon distinct processes. The
great spinous process seems completely to fill up the interval which properly exists
between the postzygapophyses. The posterior face of this process is slightly excavated
in the middle of its lower half. Its sides are also a little concave, so that the top
swells out into a sort of knob with overhanging margins.
The posterior part of the floor of the trivertebral bone is broken away ; but the hinder
face of each lateral mass exhibits a transversely elongated articular surface ( b , b), concave
from above downwards, so as to resemble a segment of a hollow cylinder, the axis of
which is directed from within outwards and very slightly backwards.
The inferior face of the trivertebral bone presents the arched surface, flatter behind
than in front, of the continuously ossified central portions or bodies of the vertebrae,
and, external to these, two pairs of apertures which perforate this face of the bone at
its outer margin. The anterior of these apertures is very much larger than the poste-
rior, and corresponds with the inner end of the middle transverse process, opening just
behind the inner end of the first rib. Strictly speaking, the foramen seen upon the
front face of the bone (Plate VII. fig. 5, d) forms one of this series of foramina (all of
which are the terminations of short passages leading into the spinal canal) ; so that, as
upon the upper, so on the under surface of the trivertebral bone, there are three pairs
of foramina in communication with the spinal canal, and of these the middle pair are,
in each series, the largest.
The homologies of the three vertebrae which compose the trivertebral bone are deter-
mined by the implantation of the head of the first rib into the great fossa between the
lateral processes of the first and second. The vertebra which yields the anterior wall of
the fossa is clearly the last cervical, and that which furnishes the posterior wall is the
first dorsal. Plence the trivertebral bone is composed of the last, or seventh, cervical and
the first and second dorsal vertebrae.
The remaining Dorso-lumbar Vertebrae. — Of these vertebrae thirteen are preserved.
The anterior twelve have plainly been immoveably united together into a continuous
arched tunnel or tubular bridge of bone, partly by anchylosis and partly by the manner
in which their apposed surfaces interlock (Plate VIII. figs. 1-7).
The four anterior vertebrae (figs. 1, d. 1. 3, 4, 5, 6) are so completely anchylosed together
that almost all traces of their original distinctness are lost. Persistent sutures, of a cha-
racter intermediate between a “ harmonia ” and a serrated suture, separate the fourth
vertebra (d. 1. 6) from the fifth, and the latter from the sixth ; but the sixth and the
seventh ( d . 1. 9) are completely fused into one bone. Between the eighth and ninth
vertebrae a suture is interposed, and also between the ninth and the tenth, at least on
the left side. The tenth and the eleventh [d. 1. 13) are completely anchylosed above,
while the suture seems to have persisted below *.
* It is convenient to speak of the first, second, (fee. of the thirteen vertebrae which succeed the trivertebral
bone ; but it must be recollected that the first of these is the third of the dorso-lumbar series, the second the
fourth dorso-lumbar, and so on, the number of any one of these vertebrae in the dorso-lumbar series being
MDCCCLXV. L
64 PROFESSOR HIJXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
Thus far, no trace of distinct articular processes is visible upon these vertebra ; but
the hinder face of the eleventh vertebra ( d . 1. 13) presents certain irregular elevations
and depressions, which interlock with corresponding ridges and cavities of the anterior
face of the twelfth vertebra. The hinder face of the twelfth (d. 1. 14) and the front
face of the thirteenth vertebra ( d . 1. 15) are in like case. I shall return to the con-
sideration of the character of these irregular articular elevations and depressions after
describing the general form of the vertebrae.
In all but the first, second, third, eleventh, and thirteenth vertebrae, the parts repre-
senting the vertebral centra are broken away, but, when they remain, they are so similar
to one another that their form was, doubtless, essentially the same throughout. Each
centrum is a comparatively thin bony plate, bent so as to be convex downwards and
concave upwards, and presenting a much flatter curve in the anterior than in the poste-
rior part of the column. In front, the central plate is not more than OT inch thick in
the middle, but it becomes thicker posteriorly, so that the centrum of the eleventh
vertebra is 045 inch thick; that of the thirteenth vertebra is OT inch thinner. At
the sides and above, the curved central part of the vertebra passes into the lateral pro-
cesses and upper arches, which last are slightly concave downwards in the first vertebra,
flat in the middle vertebrae, and somewhat arched again in the thirteenth. The contour
of a transverse section of the spinal canal is a transversely elongated oval in the first
vertebra (fig. 3), is more nearly round, but flattened at the top, in the middle vertebrae
(d.l. 12), and is a vertically elongated oval in the thirteenth vertebra (d. 1. 15).
The spinous and transverse processes of the vertebrae are represented by three crests
or ridges of bone. One of these (Plate VIII. fig. 2, a , b), vertical, and situated in the
middle line of the dorsal surfaces of the arches of the vertebrae, represents the spinous
processes; while the lateral crests (<?,<?), directed obliquely upward and downwards,
answer to transverse, accessory, and mammillary processes. As the latter ridges become
directed more upwards towards the hinder part of the dorsal region, the total width of
the column lessens, and the grooves between the middle and the outer ridges become
deeper in the same direction. Thus, anteriorly, the column is fully six inches broad,
while at the eleventh vertebra the distance from one external ridge to another is hardly
half this amount.
The first vertebra (d. 1. 3) is as broad and depressed as the trivertebral bone. Viewed
in front (Plate VIII. fig. 3), the neural canal is seen not to take up more than one-fourth
of the face of the bone, the rest of which is occupied by two broad expanded transverse
processes, directed very slightly upwards as well as outwards. The under half of each
of these processes presents an elongated articular facet (a, a'), convex from above
downwards, slightly concave from side to side, which corresponds with, and is received
into, the concave articular surfaces upon the hinder face of the trivertebral bone.
always greater by two than its number reckoned as one of tbe thirteen. In order to avoid confusion in describing
each vertebra, I shall occasionally give after it its number in the dorsal lumbar series, e. g. (d. 1. 3), (d. 1. 6),
by which it is indicated in the figures.
PEOFESSOE HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON. 65
Seated upon the upper face of the neural arch are two other oval articular surfaces
(b, b'), which answer to the postzygapophysial surfaces upon the under surfaces of the
hinder part of the neural arch of the trivertebral bone.
The inner part of each of these articular faces is convex in all directions ; the outer
is concave from side to side, convex from before backwards ; behind each lies a transverse
fossa.
The outer ends of the transverse processes are obliquely truncated, and each presents
two articular facets, an anterior and inferior, larger, and a posterior and superior smaller,
which articulate with corresponding facets upon the capitulum and tuberculum of the
attached rib. A well-marked notch separates the hinder face of the transverse process of
the first from that of the second vertebra ; and the intervertebral foramen is situated on
the same level as this notch, on the one hand, and the anterior inferior facet, on the
other, or about halfway between the upper and lower faces of the bone.
The transverse process of the second vertebra ( d . 1. 4) presents two oval articular
facets for the head of a rib, more nearly equal and more nearly on a level than those of
the first vertebra. The transverse process of the third vertebra is broken on the left
side ; but on the right side, traces of an elongated costal facet are visible.
The ends of the lateral ridges representing the transverse processes of the fourth,
fifth, sixth, and seventh vertebrae are broken away.
In the eighth, ninth, tenth, and eleventh vertebrae (Plate VIII. fig. 7, d. 1. 10, 11, 12)
they are preserved on the left side, broken away on the right ; on the twelfth vertebra
the corresponding ridges are broken on both sides.
I find no trace of articular surfaces for ribs on the lateral ridge continued along the
eighth, ninth, tenth, and eleventh vertebrae, which, as I have stated, is entire on the left
side ; but the upper and inner surface of the ridge is rounded and marked by longi-
tudinal striations (fig. 7). The outer surface is rough and irregular, opposite the ante-
rior part of each vertebra, and raised into an irregular tubercle posteriorly.
The spinous processes of all the vertebrae are broken short off; that of the first is
almost obsolete, being a mere ridge sloping back towards the second, into which it is
continued. The anterior edge of the process is so much inclined backwards and
upwards as to afford free play to the knobbed head of the spinous process of the triver-
tebral bone (fig. 2).
The spinous process of the second vertebra ( d . 1. 4) is 04 inch thick where it is
broken through, and had probably a considerable height. A distinct interval separates
it posteriorly from the thin anterior edge of the spinous process of the third vertebra,
which is much thinner, and is anchylosed with its successors, as far as the eleventh inclu-
sive, into a long continuous crest ; slight traces of the original separation of the several
spinous processes, however, are visible at the base of the crest, and they may have
been distinct at their apices. The crest gradually increases in thickness to the sixth
vertebra (d. 1. 8) (where it attains 0*75 inch), and then gradually diminishes. The
spinous process of the twelfth vertebra (d. 1. 14) may have been distinct down to its
L 2
66 PEOFESSOE HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
base ; and the posterior edge of the thin ridge, which is all that is left of the process,
appears to incline upwards and forwards.
The foramina for the exit of the spinal nerves are not intervertebral in the ten
anterior vertebras, but perforate the bony substance of each vertebra nearer its posterior
than its anterior boundary. Of these foramina there are two, on each side, for the five
anterior vertebrae ; one, larger, below the lateral apophysial ridge ; and one, smaller,
above, or upon, this ridge at the posterior boundary of each vertebra.
The larger foramen approaches the outer margin of the apophysial ridge, or seems to
be situated higher up, in each successive vertebra from the first to the seventh. Beyond
this point the level of the foramen descends somewhat. The eleventh vertebra ( d . 1. 13)
appears to have possessed a simple intervertebral notch posteriorly, on the left side ; but,
on the right, a bar of bone is preserved, separating an anterior foramen from the rest of
the notch, which receives a process of the twelfth vertebra. The arrangement appears
to be the same in the twelfth vertebra ( d . 1. 14) ; that is to say, the apparent notch has
been divided by a bar of bone into an anterior nervous foramen, and a posterior articular
fossa.
I have briefly referred, above, to the articular surfaces of the eleventh and twelfth
vertebrae, which are exceedingly irregular and distorted, apparently from partial anchy-
losis and filling up with osseous matter. A notion of their general character may best
be obtained by the study of the posterior face of the twelfth vertebra ( d . 1. 14). On
the upper part of the neural arch, on each side of the spine of this vertebra, irregular
and partially obliterated posterior oblique processes, or postzygapophyses, are discern*-
ible. The zygapophysis is separated by a depression, or groove, directed from without
obliquely downwards and inwards, from a wedge of bone which terminates the apophy-
sial ridge. Inferiorly and externally, this wedge presents a slightly concave articular
facet, separated by a deep fossa from a tuberosity with a rounded surface, which passes
down into the body of the vertebra. On the same level as this fossa, there projects from
the front surface of the vertebra a triangular process, which fits into a corresponding
fossa of the eleventh vertebra. The front face of the thirteenth vertebra ( d . 1. 15), again,
presents, on each side of the neural spine, pits, the floors of which answer to the anterior
oblique processes, or prezygapophyses; outside of these are ridges, which fit into the fossae
between the postzygapophysis of the twelfth vertebra and the wedge-shaped process ;
external to the ridges are fossae which receive those wedge-shaped processes ; and exter-
nal to and below these, again, are the remains of processes which were received into the
deep fossae mentioned above.
Except in the region of these articular processes, neither the anterior nor the poste-
rior ends of the thirteenth vertebra (Plate VIII. figs. 6 & 7, d l. 15) are entire. Of the
spinous process, only the base is left ; it thins off anteriorly to a natural edge, which is
inclined upwards and backwards, and seems to have been quite free. Posteriorly, it
becomes rapidly thicker ; but its mode of termination cannot be ascertained. The large
nervous foramen perforates the wall of the vertebra, on a level with the articular pro-
PROFESSOR HUXLEY OX THE OSTEOLOGY OE THE GENUS GLYPTODON. 67
cesses, and bifurcates externally, so that one of its apertures ends above, and the other
below, a stout bar of bone (Plate VIII. fig. 6, a), nearly an inch thick, which ends poste-
riorly in a raised curved ridge, forming the anterior boundary of a semicircular groove.
The spinal canal in the thirteenth vertebra is, as I have said, oval in shape, the long
diameter of the oval (T5 inch in length) being vertical, the short diameter (IT inch)
transverse.
As, in the anterior part of the lumbo-sacral region, this canal has a very different
shape, it is probable that two or three vertebrae are wanting in this portion of the
spinal column.
The Sacrum and Coccygeal Vertebrae. — The “ sacrum,” composed of anchylosed lumbar,
proper sacral, and coccygeal vertebrae, contains at fewest twelve, and perhaps thirteen
vertebrae. The centra of the two hindermost lumbar vertebrae and of the two proper
sacral vertebrae, which follow them (Plate IX. fig. 2), are thin and broad bony plates,
flat above, and slightly concave from side to side below, exhibiting a most marked con-
trast to the semicylindrical form of the same part in the hindermost of the thirteen
vertebrae described above. The plane of the plate formed by the centra of the anchy-
losed lumbar vertebrae is inclined, upwards and forwards, to pass into the general curve
of the dorso-lumbar region. The plane of the centra of the two succeeding sacral ver-
tebrae, on the other hand, is horizontal ; and it is obvious, from the characters of the
rest of the sacrum, that the centra of the following vertebrae, to the end of the sacral
region, were arranged in an almost semicircular curve, the chord of which is about 18
inches long (Plate IX. fig. 3). The posterior face of the hindermost coccygeal vertebra
(Plate IX. fig. 1, a) is broad, oval, and very slightly concave, like the face of an ordi-
nary vertebral centrum ; but the centrum of the penultimate coccygeal vertebra is much
flatter and narrower; and this flattening and narrowing become still more marked in
the centrum of the antepenultimate vertebra and of that which precedes it, or the fourth
from the end. From this point to the two anterior sacral vertebrae the floor of the
sacral canal is completely broken away, but there can be little doubt that the missing
centra were represented by a broad and flat bony plate.
The neural arches are but imperfectly preserved, except in the lumbar region and
the anterior part of the sacrum. They are thin, and are separated by large intervertebral
foramina. In the lumbar vertebrae these foramina pass downwards and backwards into
grooves which mark the sides of the central plate. Well-defined depressions upon the
sides of the sacral crest lead upwards and backwards to the canals which pass between
that crest and the ilia.
The four last coccygeal intervertebral foramina are still larger, and indicate the
passage of large nerves to the muscles moving the tail.
The spinous processes of all the vertebrae which enter into the sacrum, up to the fourth
from the end inclusively, are anchylosed together into a long and strong osseous crest
(Plate IX. figs. 3 & 4), which expands above, so as to present a broad and very rugged
superior face. This crest is 8 inches high in front, but slowly diminishes as it follows
68 PROFESSOR HTJXLET OX THE OSTEOLOGY OE THE GENUS GLYPTODON.
the curve of the centra posteriorly, to 5 inches. The spinous process of the penultimate
coccygeal vertebra is very thick, but it is broken short off. It was probably not less than
4 inches high, and afforded a middle point of support for the dermal shield between the
ischial protuberances (Plate IX. fig. 1).
The sides of the two anterior sacral vertebrae and the corresponding part of the sacral
crest are anchylosed with the inner edges of the iliac bones, so that only a narrow oval
space, left between these parts, near the upper edge of the crest, and the small canals
above mentioned, allow of any communication between the region in front of, and that
behind the ilia.
Behind this point the vertebrae are devoid of transverse processes as far as the fourth
from the end. But the antepenultimate had a long and slender transverse process on
each side ; the penultimate possesses an equally long but much stouter process, and the
last coccygeal vertebra has extremely thick processes of the same length. The enlarged
distal ends of these processes unite with one another and with the inner surfaces of the
ischia (Plate IX. figs. 1, 2, 4).
Caudal Vertebra. — No caudal vertebrae existed among the remains of this specimen of
Glyptodon.
Of the Vertebral Column as a whole. — It appears from the foregoing description that
the atlas of the Glyptodon was moveable upon the odontoid vertebra ; but that the latter
was anchylosed with the third and fourth cervical vertebrae into one short bone, move-
able upon the fifth cervical ; of the fifth and sixth cervical vertebrae no remains exist.
The seventh cervical is anchylosed with the first and second dorsal into a single “ triver-
tebral bone,” upon the front part of which the sixth cervical was certainly moveable ;
while the hinder part of it freely articulates with the third dorsal, so that the bone
was capable of motion through a certain vertical arc.
Beyond this point, as far as the fourteenth dorso-lumbar vertebra, the vertebrae are so
connected by complete, or partial, anchylosis, that it is impossible any motion should
have taken place between them ; and it is probable, though not so certain, that the
fifteenth dorso-lumbar vertebra was similarly fixed.
Between this and the two hindermost lumbar vertebrae, which are completely anchy-
losed together and with the sacral vertebrae, there is a hiatus, but the condition of the
two latter is not such as to lead to the supposition that the intermediate vertebrae were
less firmly united than they.
The free cervical portion of the vertebral column must have been remarkably short,
probably not exceeding 8 inches in length, and the cervical vertebrae were most likely
arranged in a nearly straight line.
The trivertebral bone and the thirteen following dorso-lumbar vertebrae, when articu-
lated together, form one great curve, concave downwards or towards the visceral cavity,
the curve being much sharper in the anterior than in the posterior part of the column.
Measured along its curvature, this part of the vertebral column is about 35 inches long.
At the anterior part of the sacral region the lumbar curve passes into the straight
PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON. 69
line of the two anterior sacral vertebree, behind which commences the great sacro-
coccygeal curve, concave towards the cavity of the pelvis. The lumbo-sacral is very
nearly as long as the dorso-lumbar region, so that the vertebral column, from the last
cervical to the last coccygeal, may be said to form two subequal arches with a common
pier, formed by the proper sacral vertebrae.
Description of the Plates.
PLATE IV.
Figs. 1 & 3. Upper and under views of the skull of the “new specimen” of Glyptodon
clavipes.
Figs. 2, 4, & 5. Upper, under, and side views of the hinder part of the skull of the
“typical specimen” of Glyptodon clavipes.
All reduced to one-half the natural size.
PLATE V.
Fig. 1. Side view of the skull of the new specimen of Glyptodon clavipes.
Fig. 2. The left half of the mandible of the same, one-half the natural size.
Fig. 2°. The ascending ramus of the mandible, viewed from behind.
Figs. 3 & 4. Grinding-surfaces of the teeth, of the natural size.
PLATE VI.
Front view, and
Back view of the skull of the new specimen of Glyptodon clavipes.
View of the occipital face of the skull of the typical specimen.
Front view, and
Upper view of the mandible of the new specimen.
All reduced to one-half the natural size.
PLATE VII.
Figs. 1 & 2. Front and back views of the fragment of the atlas.
*** The artist has inadvertently inverted each figure, so that the lower
side of the bone is turned upwards, and vice versa.
Fig. 3. The trivertebral bone, seen from above.
Fig. 4. The trivertebral bone, from behind ; d, the first rib, in place.
Fig. 5. The trivertebral bone, from in front.
Fig. 6. The trivertebral bone, viewed from the right side.
Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
70 PROFESSOR HUXLEY ON THE OSTEOLOGY OF THE GENUS GLYPTODON.
Fig. 7. The fragment of the first rib of the right side, viewed from without.
Figs. 8, 9, 10. Front, inner, and outer views of the fragment of the third left rib.
PLATE VIII.
Fig. 1. The third to the ninth dorso-lumbar vertebrae, viewed laterally.
Fig. 2. The same, viewed from above.
Fig. 3. The anterior face of the third dorso-lumbar vertebra.
Fig. 4. The posterior face of the sixth dorso-lumbar vertebra.
Fig. 5. The anterior face of the twelfth and thirteenth dorso-lumbar vertebrae. It is
much mutilated, especially below and on the left side, none of the centrum
of the twelfth vertebra remaining.
Fig. 6. The tenth to the fifteenth dorso-lumbar vertebrae, viewed laterally.
Fig. 7. The same, from above.
All reduced to one-half the natural size.
PLATE IX.
Back view of the pelvis of Glyptodon clavipes.
Front view of the same.
Side view of the same.
Upper view of the same.
All these figures are reduced to one-sixth the natural size.
-8. Outer, inner, back and under views of the fragment pf the anchylosed
odontoid, third, and fourth cervical vertebrae, one-half the natural size.
a the upper, and b the lower end of the bone in each figure, which is
reduced to one-half the natural size.
Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.
Figs. 5-
Bub. Trans. MD C CGLXV Biota IV".
f
BO
,di
pEbdeben. daL feifli.
"W/West imp.
Tkil/. 2WMDCCGLXV. FlaXa V.
J-Erxlebeii dsL
W.'West imp.
Phl.TrcLOS.y~MZlJiy. TlateVl
.Pluls. 'Trans. MDCGCLXV. Exrtb YII.
J.Eiieben. del. .felifli.
T/Ofest ingo.
BdL.Tnms. MD CGCW. P1.YII1
A L. 11.
eLl.11.
Al.15.
■A l. 13.
Pig. 7.
"VTOfestimp.
J.EcxLeben- deL
JPkiL.Trans. MD CCCLXY. Flabb IX.
"W.West imp.
J.Endeben. del &]ifh..
1 71 ]
*
III. Investigations of the Specific Heat of Solid Bodies.
By Hermann Kopp. Communicated by T. Graham, Esq., F.B.S.
Received April 16, — Read May 12, 1864.
I. Historical Introduction.
I. About the year 1780 it was distinctly proved that the same weights of different
bodies require unequal quantities of heat to raise them through the same temperature,
or on cooling through the same number of thermometric degrees, give out unequal quan-
tities of heat. It was recognized that for different bodies the unequal quantities of heat,
by which the same weights of different bodies are heated through the same range, must
be determined as special constants, and considered as characteristic of the individual
bodies. This newly discovered property of bodies Wilke designated as their specific
beat , while Crawford described it as the comparative heat, or as the capacity of
bodies for beat. I will not enter upon the earliest investigations of Black, Irvine,
Crawford, and Wilke, with reference to which it may merely be mentioned that
they depend essentially on the thermal action produced when bodies of different tem-
peratures are mixed, and that Irvine appears to have been the first to state definitely
and correctly in what manner this thermal action (that is, the temperature resulting
from the mixture) depends on the original temperature, the weights, and the specific
heats of the bodies used for the mixture. Lavoisier and Laplace soon introduced the
use of the ice-calorimeter as a method for determining the specific heat of bodies ; and
J. T. Mater showed subsequently that this determination can be based on the observa-
tion of the times in which different bodies placed under comparable conditions cool to
the same extent by radiation. The knowledge of the specific heats of solid and liquid
bodies gained during the last century, and in the first sixteen years of the present one,
by these various methods, may be left unmentioned. The individual determinations
then made were not so accurate that they could be compared with the present ones,
nor was any general conclusion drawn in reference to the specific heats of the various
bodies.
2. Dulong and Petit’s investigations, the publication of which commenced in 1818,
brought into the field more accurate determinations, and a general law. The investiga-
tions of the relations between the specific heats of the elements and their atomic weights
date from this time, and were afterwards followed by similar investigations into the rela-
tions of the specific heats of compound bodies to their composition. In order to give a
general view of the results of these investigations, it is desirable to present, for the ele-
ments mentioned in the sequel, a synopsis of the atomic weights assumed at different
MDCCCLXV. M
72
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
times, and of certain numbers which, stand in the closest connexion with these atomic
weights.
Berzelius’s atomic
weights.
Regnault’s thermal
atomic weights.
Usual equivalent
weights.
Modem
atomic weights.
Aluminium
A1 = 13-7
A1 = 13-7
A1 = 13-7
A1 = 27-4
Antimony
Sb = 61
Sb = 61
Sb =122
Sb =122
Arsenic
As = 37-5
As = 37-5
As = 75
As = 75
Barium
Ba = 68-5
Ba = 68-5
Ba = 68-5
Ba =137
Bismuth
Bi =105
Bi =105
Bi =210
Bi =210
Boron
B = 10-9
B = 10-9
B = 10-9
B = 10-9
Bromine
Br = 40
Br = 40
Br = 80
Br = 80
Cadmium
Cd = 56
Cd = 56
Cd = 56
Cd =112
Calcium
Ca = 20
Ca = 20
Ca = 20
Ca = 40
Carbon
C = 6
C = 12
C = 6
C = 12
Chlorine
Cl = 17-75
Cl = 17-75
Cl = 35-5
Cl = 35-5
Chromium
Cr = 26-1
Cr = 26-1
Cr = 26-1
Cr = 52-2
Cobalt
Co = 29-4
Co = 29-4
Co = 29-4
Co = 58-8
Copper
Cu = 31-7
Cu = 31-7
Cu = 31-7
Cu = 63-4
Fluorine
FI = 9-5
FI = 9-5
FI = 19
FI = 19
Gold
Au = 98-5
Au = 98-5
Au =197
Au = 197
Hydrogen
H = 0-5
H = 1
H = 1
Iodine
I = 63-5
I = 63-5
I =127
I =127
Iridium
Ir = 99
Ir = 99
Ir = 99
It =198
Iron
Fe = 28
Fe = 28
Fe = 28
Fe = 56
Lead
Pb =103-5
Pb =103-5
Pb =103-5
Pb =207
Lithium
Li = 7
Li = 3-5
Li = 7
Li = 7
Magnesium
Mg= 12
Mg= 12
Mg= 12
Mg= 24
Manganese
Mn= 27-5
Mn= 27-5
Mn= 27-5
Mn= 55
Mercury
Hg =100
Hg = 100
Hg = 100
Hg=200
Molybdenum
Mo= 48
Mo = 48
Mo= 48
Mo= 96
Nickel
Ni = 29-4
Ni = 29-4
Ni = 29-4
Ni = 58-8
Nitrogen
N = 7
N = 7
N = 14
N = 14
Osmium
Os = 99-6
Os = 99-6
Os = 99-6
©s =199-2
Oxygen
0=8
0=8
© = 16
Palladium
Pd = 53-3
Pd = 53-3
Pd = 53-3
Pd =106-6
Phosphorus
P = 15-5
P = 15-5
P = 31
P = 31
Platinum
Pt = 98-7
Pt = 98-7
Pt = 98-7
Pt =197-4
Potassium
K = 39-1
K = 19-55
X = 39-1
K = 39-1
Rhodium
Rh= 52-2
Rh= 52-2
Rh = 52-2
Rh =104-4
Rubidium
Rb= 85-4
Rb= 85-4
Rb= 85-4
Selenium
Se = 39-7
Se = 39-7
Se = 39-7
Se = 79-4
Silicium
Si = 21
Si = 14
Si = 28
Silver
Ag = 108
Ag = 54
Ag =108
Ag =108
Sodium
Na= 23
Na = 11-5
Na = 23
Na = 23
Strontium
Sr = 43-8
Sr = 43-8
Sr = 43-8
Sr = 87-6
Sulphur
S = 16
S = 16
S = 16
S = 32
Tellurium
Te = 64
Te = 64
Te = 64
Te =128
Thallium
T1 =204
Tl =102
Tl =204
Tl =204
Tin
Sn = 59
Sn = 59
Sn = 59
Sn =118
Titanium
Ti = 25
Ti = 25
Ti = 25
Ti = 50
Tungsten
W = 92
W = 92
W = 92
W =184
Zinc
Zn = 32-6
Zn = 32-6
Zn = 32-6
Zn = 65-2
Zirconium
Zr = 33-6
Zr = 44-8
Zr = 89-6
For each of the previous columns the relation of the numbers to each other is alone
important, and not the number which is taken as unit or starting-point. Berzelius’s
atomic weights and Regnault’s thermal atomic weights are corrected with the nearest
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
73
and most trustworthy experimental determinations, without alteration of the bases for
the adoption of these numbers. The numerical relations presented in the above Table
require, from the chemical point of view, no further explanation. The relations of these
numbers to the specific heat form the subject of the investigations which are presented
in the sequel.
3. The experiments by which Dulong and Petit * * * § showed, in the case of mercury
various solid metals, and glass, that the specific heat increases with increasing tem-
perature, were made by the method of mixtures. They determined at ordinary tem-
peratures the specific heats of a greater number of elements by the method of cooling f.
They found that when the numbers in the first column in § 2 corresponding to the
elements Bi, Pb, Au, Pt, Sn, Zn, Cu, Ni, Fe, and S (the Berzelian atomic weights)
are multiplied by the respective specific heats of these bodies, approximately the same
number is obtained ; and that approximately the same number is also obtained when
Ag, \ Te, and f Co are multiplied by their corresponding specific heats. They were
of opinion that the atomic weights of the elements could and should be so selected that,
when multiplied by the specific heats, they should give approximately the same number
as product. This observation and this view, which Dulong and Petit stated in 1819 in
the following manner, “The atoms of all simple bodies have all exactly the same
capacity for heat,” have since that time been known as Dulong and Petit’s Law.
I shall not here dwell upon Potter’s investigations on the specific heat of metals
and on the validity of Dulong and Petit’s lawj, but proceed directly to discuss
Neumann’s investigations, which rank worthily by the side of those of Dulong and
Petit.
4. In his “Investigation on the specific heat of Minerals,” Neumann (in 1831) first
published § more accurate determinations of the specific heats of solid compounds. He
investigated a large numbfer of such compounds, especially those occurring in nature,
partly by the method of mixture, and partly by the method of cooling ; and he deter-
mined the sources of error in both these methods, and the corrections necessary to be
introduced. In a postscript to this paper, he mentioned that he continued the investi-
gations with an apparatus which, compared with that he had previously used, promised
far greater accuracy in the individual results, without needing tedious and troublesome
reductions. This apparatus, by means of which the specific heats of solid bodies, which
may be heated in a closed space surrounded by steam, can be determined with great
accuracy, he has not described ||.
Of the general results of Neumann’s investigations, one must be particularly men-
* Annales de Chimie et de Physique, [2] vol. vii. p. 142. + Ibid. vol. x. p. 395.
+ Edinburgh Journal of Science, New Series, vol. v. p. 75, and vol. vi. p. 166. J. F. W. Johnston’s remarks,
vol. v. p. 278. I only know these papers from Berzelius’s e Jahresbericht,’ vol. xii. p. 17, and Gehxer’s
‘ Physicalisches Worterbuch,’ new edition, vol. x. part 1, p. 805 et seq.
§ Poggendorff’s ‘Annalen,’ vol. xxiii. p. 1.
|| Pape (Poggendorff’s ‘ Annalen,’ vol. cxx. p. 337) has recently described this apparatus. I have had no
M 2
74
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
tioned, that a dimorphous substance has the same specific heat in its two conditions.
This he showed was the case with arragonite and calcite, and with iron pyrites and
marcasite. But the most important is the discovery that in analogous compounds the
products of the atomic weights into the specific heats are approximately equal. Neu-
mann stated this last observation in the following manner : — “ In bodies of analogous
chemical composition the specific heats are inversely as the stochiometrical quantities,
or, what is the same, stochiometrical quantities of bodies of analogous chemical com-
position have the same specific capacity for heat.” Neumann adduced 8 carbonates,
4 sulphates, 4 sulphides (Me S), 5 oxides (Me O), and 3 oxides (Me203), as showing
this regularity, which is to be denoted as Neumann’s law *.
5. Soon after the publication of Neumann’s researches in 1833, Avogadro published f
a “ Memoir on the Specific Heat of Solid and Liquid Bodies.” He there gave a number
of determinations of the specific heat of solid bodies made by the method of mixture.
As far as can he ascertained by comparison with the most trustworthy of our newer de-
terminations, these results are by no means so accurate as those of Neumann; but they
are far more accurate than those which had been obtained up to about 1830, and many
of them come very close to the best of our modern results. It would be unjust to
Avogadro’s determinations $ to judge them all by one case, in which he obtained a
totally erroneous result (for ice, by a modified method) ; and by the circumstance that in
a subsequent memoir § he gives specific heats for several elements as deduced from his
experiments, which are decidedly incorrect ||. Avogadro recognizes the validity of
Hulong and Petit’s law. With reference to the specific heats of compound bodies, he
considers that he had established, with tolerable probability, that for solid and liquid
bodies the same regularity prevails which he had previously deduced for gases from
Dulong’s experiments. That is, “ that the specific heat of the atom of a compound body
is equal to the square root of the integral or fractional number expressing the atoms or
parts of atoms which go to form the atom of the compound body such as it exists in the
solid or liquid state, taking as unity the specific heat of the atom of a simple body in the
samestate.” He observes that there is a difficulty incidental to the application of this
law to solid and liquid bodies, which is not met with in the case of gaseous bodies,
in which the composition by atoms or by volumes is held to be directly given by
opportunity of seeing Neumann’s memoir cited by Pape, “ Commentatio de emendenda formula per quam calores
corporum specifici ex experimentis metbodo mixtionis institutis computantur.” Regiomonti, 1834.
* The objections of Regnault (Ann. de Chim. et de Phys. [3] vol. i. p. 131) as to the inadequacy of the
proofs adduced 'by Neumann in support of the law do not apply.
t Ann. de Chim. et de Phys. [2] vol. lv. p. 80, as an abstract from * Memorie della Societa Italiana delle
Scienze residente in Modena,’ t. xx. Fascicolo 2 di fisica’.
+ They are also found in Gmexin’s ‘ Handbuch der Chemie,’ 4 Auflage, vol. i. in the Tables, pp. 215-218 et seq.
§ Ann. de Chim. et de Phys. [2] vol. lvii. p. 113.
|| I only know Avogadro’s investigations from the abstracts published in the Ann. de Chim. et de Thys., and
am not aware whether the hold corrections of Avogadro urged by Regnault (Ann, de Chim. et de Phys. [2]
vol. lxxiii. p. 10) were used in all his experiments, or only in some.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
75
observation. This difficulty consists in knowing what constitution is to be assigned
to the body in question for the solid or liquid condition ; this constitution, from the
conclusions derived from his theoretical considerations, would often be different from
that which the body has in the state of gas or vapour. His considerations led him
to assume the atomic weights of many elements different from those which Berzelius
had given : Avogadro described the atoms, to which the weights assumed by him refer,
as thermal atoms.
6. B. Hermann published in 1834 a memoir “ On the Proportions in which Heat
unites with the Chemical Elements and their Compounds, and on the Combining
Weights considered as quotients of the capacity for Heat of Bodies into their Specific
Gravities”* * * §. He gives there a great number of determinations of the specific heat of
solid bodies (of a few elements, but chiefly of compound bodies). He made a few ex-
periments in which he used Lavoisier and Laplace’s calorimeter f ; but by far the
greater number of determinations are made by the method of cooling Many of his
results approach very closely to those which are at present considered accurate, but
they are in so far untrustworthy that a considerable number among them are decidedly
incorrect.
As for Hermann’s theoretical results, it must be borne in mind that, regarding
matter as he does, not from the point of view of the atomic but of the dynamical
theory, he puts the idea of combination weights in the place of the idea of atomic
weights. The propositions which he endeavours to establish are the following. The
quotients obtained by dividing the specific gravities cf the elements § in the solid state
by their specific gravities in the gaseous state, are either equal or stand to each other
in simple ratios ; they are 1,2 15 times as much as a certain base. The
same is the case with the products of the specific gravities of the solid elements into
their specific heats, that is, with their relative heat ; and the number indicating the
multiple for a given element is the same for both the above relations. It follows from
this that the combining weights m of the elements are proportional to the quotients of
their relative heats into their specific gravity in the solid condition ; that the products
of the specific heats and the combining weights for different elements are equal to a
constant, and that from the known combining weight of an element its specific heat in
the solid form may be calculated (it is equal to 0'3m7 5, where m is the combining weight
of the substance in question referred to oxygen = 1). For several elements (phosphorus,
* Nouveaux Memoires de la Societe Imperiale des Naturalistes de Moscou, vol. iii. p. 137.
+ Hermann tried to alter this apparatus so as to make it serve for measuring the change of volume which
takes place when ice melts ; but he did not further follow this application of the modified apparatus.
X They are found not quite complete in Gmelin’s £ Handbuch der Chemie,’ 4 Auflage, in the Tables,
pp. 215-218 et seq.
§ Hermann considers that the specific gravities of the elements in the state of gas or vapour are either
obtained by observation, or may be theoretically deduced by assuming that they are in the ratio of the com-
bining weights.
76
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
tellurium, cadmium, and silver for instance) atomic weights are taken which differ from
those of Berzelius. In the case of the sulphides, the specific heats may be calculated
from those of the constituents, assuming that the specific heats of the elements in these
compounds are the same as in the free state. The same holds good for several
chlorides and for basic metallic oxides, if the specific heats of chlorine and of oxygen,
as given by the above formula, are taken as basis. But in acids a smaller specific heat
must be taken for oxygen (one half in several acids and null in phosphoric acid) ; and
there are even compounds (cassiterite, e. g., or arsenious acid), in which the same element
is contained partly with the normal and partly with the modified specific heat* * * §. For
oxygen salts it is to be assumed that both the acid and the base have the same specific
heat as in the free state, and hence the specific heat of one constituent (of the acid, for
instance) may be calculated, if that of the salt and that of the other constituent (the
base) is known ; and it is also found that the specific heat of chromic acid in the neu-
tral and in acid chromate of lead is the same.
This memoir of Hermann’s did not become much known. Unacquainted with it,
other philosophers have subsequently developed independently similar opinions.
7. In 1835 Rudberg described a method j*, which, by ascertaining the heat developed
when salts are dissolved in water, in experiments in which the proportion of the salt
to the water was constant, but the temperature of the salt varied, should give a means of
at once determining the specific heat of the salt, and of the heat which was either absorbed
or became free. Yet the numbers which he obtained from his experiments for the
specific heat of solid salts are undoubtedly erroneous.
Dumas $ (in 1838) discussed the possibility of determining the specific heat of organic
bodies by the following process. A platinum vessel containing the substance in ques-
tion, along with a thermometer, is to be heated to 30° or 40°, and then brought into a
vessel provided with a second thermometer, and containing water, the temperature
being about 5° or 6° lower than that of the surrounding room. When the temperature
has risen to the same extent above that of the room, both thermometers are to be
observed. I know no determinations made by this method.
8. In 1840 Regnault commenced the publication of a series of important investiga-
tions on specific heat which he had made. As they are generally known, I may be
more brief in enumerating the contents of the individual publications. In the first
which he published, Regnault developed § the reasons which led him to prefer the
method of mixture to other processes for determining the specific heats of solid bodies ;
* Hermann designates such compounds as hermaphrodites. He thinks that an acid and a base may have the
same composition, and that they may form salts with each other. Cassiterite, for instance, he considers to be
stannate of binoxide of tin.
f Berzelius’s ‘ Jahresbericht,’ vol. xv. p. 63. Poggendorff’s ‘Annalen’, vol. xxxv. p. 474.
J Dumas’s “ These sur la question de Faction du calorique sur les corps organiques” (Paris, 1838) Ann.
der Pharm. und Chem. vol. xxviii. p. 151.
§ Ann. de Chim. et de Phys. [2] vol. lxxiii. p. 5.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
7T
he described his mode of executing this method, and published the results obtained for
a great number of elements. In a second memoir * he gave the specific heats of several
metallic alloys containing metals in simple atomic ratios, and of a great number of
solid chemical compounds ; and he published comprehensive experiments on the specific
heat of carbon in its different conditions. The investigations announced in the first
memoir f on the specific heat of organic compounds, as well as those promised in the
second memoir^ on the specific heat of sulphur at different temperatures, have not to
my knowledge been published. But in a third memoir § Regnault has investigated
the difference in the specific heats of certain metals according as they are hardened or
soft, and also with reference to sulphur according as it is in the native crystallized form,
or has solidified a longer or shorter time after being melted ; and he has more especially
tried to impart greater certainty to the method of cooling. In his subsequent inves-
tigations, however, he has only used the method of mixture as being the more certain.
These investigations || have given the specific heats of a large number of solid elements,
and also of individual compounds.
By his investigations Regnault has removed some objections which seemed to affect
Dulong and Petit’s law, and has given a great number of new cases in which it
applies. He considers <|[ this law to be universally valid, and discusses the reasons why
for individual elements the specific heats found do not quite agree with the law, but
only approximately. In his view the atomic weight of an element is to be so taken
that it agrees with Dulong and Petit’s law. He took the atomic weight of silver and
of the alkaline metals half as great, and that of carbon twice as great as Berzelius
had done. Yet with regard to selecting, by means of the specific heat, from among
the numbers which the chemical investigations of an element has given as admissible,
that which is the correct one, Regnault does not always express himself decidedly.
In the case of carbon ** and of silicium f f he mentions the possibility of their disagree-
ment with Dulong and Petit’s law. He proved the validity of Neumann’s law for a
number of cases very considerably greater than that on which it had originally been
based ; and he expressed it in a much more general form JJ. “ In all compounds of ana-
logous atomic composition, and similar chemical constitution, the specific heats are
approximately inversely proportional to the atomic weights. Regnault designates the
numbers agreeing with this law as thermal atomic weights. He has either determined
them directly from the numbers found for the specific heats of the elements in the free
* Ann de Chim. et de Pkys. [3] vol. i. p. 129. + Ibid. [2] vol. lxxiii. p. 71.
t Ibid. [3] vol. i. p. 205. § Ibid. [3] vol. ix. p. 322.
|| Ibid. [3] vol. xxvi. pp. 261 & 268 ; vol. xxxviii. p. 129 ; vol. xlvi. p. 257 ; vol. lxiii. p. 5. Comptes
Rendus, vol. Iv. p. 887.
i^[ Ann. de Cbim. et de Phys. [2] vol. lxxiii. p. 66 ; further, [3] vol. xxvi. p. 261, and vol. xlvi. p. 257.
** Ibid. [3] vol. i. p. 205. But botb before and after (Ibid. [2] vol. lxxiii. p. 71, and [3] vol. xxvi. p. 263)
Regnault inclined to tbe view that carbon, with the equivalent= 12, and the specific heat found for wood-charcoal,
must be considered as obeying Dulong and Petit’s law. ft Ibid. vol. lxiii. p. 30. Xt Ibid. vol. i. p. 199.
78
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
state, applying Dulong and Petit’s law, or indirectly by ascertaining the specific heat
of solid compounds, assuming Neumann’s law ; or finally (and only in a few cases), he
has determined them by means of their probable analogies. These are the atomic
weights given in the second column of the Table in § 2.
With regard to the relations of the specific heats of solid compounds to those of their
constituents, Regnault has shown * that with metallic alloys, at a considerable distance
from their melting-points, the specific heats may be calculated from those of their con-
stituents in tolerable accordance with the experimental results, assuming that the
specific heats of the metals are the same in the alloys as in the free state. The investi-
gation, whether for true chemical compounds there is a simple relation between their
specific heats and those of their constituent elements, Regnault has reserved *f* till the
conclusion of his experiments on the specific heats of gaseous bodies $. To my know-
ledge he has published nothing for solid bodies. But in 1862, with reference to the
relations which had been recognized between the specific heats and atomic weights of
solid, simple or compound bodies, he spoke as follows §. “ It is true that these laws, in
the case of solid bodies, only apply approximately to simple bodies and those compounds
of least complex constitution ; for all others it is impossible to pronounce anything in
this respect.” From some remarks of Regnault in reference to carbon || and silicium ^f
he considers it possible, or probable with certain elements, that they have a different
specific heat in their compounds to that which they have in the free state.
9. In 1840 De la Rive and Marcet published ** investigations on the specific heat of
solid bodies. They made their determinations by the method of cooling. They found
that, assuming Berzelius’s atomic weights, selenium, molybdenum, and wolfram fall
under Dulong and Petit’s law, which they consider as universally valid; but that
carbon forms an exception, and they consider it as probable that its true atomic weight
has not yet been ascertained. For several sulphides they found a greater specific heat
than was calculated for them, assuming that their constituents have in them the same
specific heat as in the free condition. They think that for solid as well as for liquid
and gaseous compounds the law governing the specific heat is still unknown. A sub-
sequent memoir by these physicists treated of the specific heat of carbon in its various
conditions.
10. In 1840 H. Schroder made an investigation as to what volumes are to be
assigned to the constituents of solid and liquid compounds when contained in those
compounds. In his memoirs on the subject, he expressed the view that the specific
heat of compounds depends on the specific heats of the constituents in that particular
* Ann. de Chim. et de Phys. [3] vol. i. p. 183. t Ibid. p. 132.
i Regnault has made known the results of these experiments in 1853 by a preliminary account in the Comptes
Rendus, vol. xxxvi. p. 676, and more completely in 1862 in his ‘ Relation des experiences pour determiner les
lois et les donnees physiques necessaires au calcul des machines a feu/ vol. ii. p. 3.
§ Relation, &c. vol. ii. p. 289. || Ann. de Chim. et de Phys. [3] vol. i. p. 205. Ibid. [3] vol. Ixiii. p. 31.
** Ibid. [2] vol. lxxv. p. 113. ft Ibid. [3] vol. ii. p. 121. Poggendoeee’s * Annalen/ vol. 1. p. 553.
PBOFESSOB KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
79
state of condensation in which they are contained in the compounds in question. In
1841 *, reasoning from the results of Regnault’s experiments, he endeavoured to show
that the atomic heat (that is the product of the atomic weight into the specific heat)
of a compound is equal to the sum of the atomic heats for the states of condensation
in which the elements are contained in the compound, and to ascertain what atomic heats
are to be assigned to certain elements in certain compounds. On the assumption that
the atomic heat of metals in compounds is as great as in the free state, he endeavoured
to determine the atomic heat of oxygen, sulphur, &c. in certain compounds of these
elements with the metals ; he came to the conclusion that an element (sulphur for. in-
stance) may in some compounds have an atomic heat different from that which it has in
the free state ; and the same element (sulphur or oxygen for instance) may have different
atomic heats in different compounds; but the changes in the atomic heat of an
element always ensue in simple ratios. I cannot here adduce the individual results
which he obtained when he inferred the atomic heat of an element in a compound by
subtracting from the atomic heat of the compound the atomic heat of the other
elements in it, which he had calculated either from direct determinations of their
specific heat, or from previous considerations. The essential part of Schroder’s con-
ception is that in this manner the atomic heat of a body, as a constituent of a compound,
may be indirectly determined ; and the result is that the atomic heat, at any rate of some
elements in compounds, is different from what it is in the free state, and may be different
in different compounds, and that the changes are in simple ratios. Schroder considered
also that there was probably a connexion between these changes and those of the
volumes of the elements, without, however, stating how from the one change the other
might be deduced.
11. L. Gmelin (in 1843) considered it as inadmissible, from the chemical point of view,
to assign throughout such atomic weights to the elements as to make them agree with
Dulong and Petit’s law. Certain exceptions must be admitted. Comparing the
specific heats of oxygen, hydrogen, and nitrogen for the gaseous state with the specific
heats of other elements in the solid state, he came to the conclusion that if the numbers
given in § 2 as the equivalents ordinarily assumed be taken as atomic weights, the
atomic heat of hydrogen, of nitrogen, and by far the greater number of the elements is
equal to about 3-2 ; several of them twice as great, that of oxygen one-half, that of
carbon (as diamond) one-fourth as great. With reference to the dependence of the
atomic heats of the compounds on those of the elements, Gmelin expressed the opinion J
that in general the elements on entering into compounds retain the atomic heats they
have in the free state, but for individual elements, especially for oxygen and carbon, it
must be assumed that their atomic heat changes in simple ratios with the compounds
into which they enter.
* Poggeitdoree’s ‘ Annalen,’ vol. lid. p. 269. f L. Gmelin’s ‘ Handbuch der Chemie,’ 4th ed. vol. i. p. 217.
+ Ibid. p. 222 : compare an earlier remark of Gmelin which applies to this subject (1840) in the new edition
of Gehler’s £ Physikalisches Wbrterbuch,’ vol. ix. p. 1941.
MDCCCLXV. N
80
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
12. Wcestyn was also of opinion * that the specific heats of the elements remain
unchanged when they enter into chemical compounds. In 1848 he stated as a general
proposition ; “ The quantity of heat necessary to raise the temperature of the atomic
weight of a body through 1° is equal to the sum of the quantities of heat necessary to
raise the temperature of the atoms, and fractions of atoms, through 1°”. If A is the
atomic weight and C the specific heat of a compound, alf a2, a3 ... . the atomic
weights f, and cz, c2, c3 ... . the specific heats of the elements contained in it, and
wz, n2, nz . . . . the numbers which express how many atoms of each element are con-
tained in an atom of the compound, then
AC =n1alcl -\-n2a2c2-\-nza3cz
As a proof of this law, he compared the calculated values of AC of several compounds
(metallic iodides and sulphides) and alloys with the observed values, taking Regnault’s
determinations of the specific heats of the elements and of the compounds. It follows,
further, from that proposition, that if the formula and the values for several compounds
are compared with each other, there must be the same differences of the values AC for the
same differences of formulae. WtESTYN showed by a number of examples that this is so
approximately. By means of this law, the product of the specific heat and the atomic
weight for one constituent of a compound may be found, if this is known for the compound
and the other constituents. Wcestyn deduced in this way the product for oxygen (by
subtracting from the product for different metallic oxides that found for the metals,
and from chlorate of potass that for chloride of potassium) to be 2*4 to 2T (0. = 8),
and for chlorine 3-0 to 3’5 (Cl. = 17‘75). Wcestyn finally expressed a doubt
whether Neumann’s law is universally applicable. He laid stress on the circumstance
that when two elements give different products, the difference is also met with in the
products for their analogous compounds ; and, for instance, the greater products which
mercury and bismuth have in comparison with other elements, are also met with in the
compounds of these metals.
13. Garnier (in 1852) developed the viewj, that not only in the case of elements are
the atomic weights A § inversely proportional to the specific heats C, but that the same
is the case with water || and solid compounds in whose atom n elementary atoms are
A
contained, if the so-called mean atomic weight — be compared with the specific heat C ;
for elements AxC=3, and for compound bodies ^xC= 3 (if 0=8). He endeavoured
to prove this from Regnault’s determinations of specific heats. From the latter equa-
tion he calculated the specific heat for several compounds. In the case of the basic
oxides, sulphides, chlorides, bromides, and iodides, his calculated results agree tolerably
* Ann. de Chim. et de Phys. [3] vol. xxiii. p. 295.
t Wcestyx based bis considerations on Regnatjlt’s thermal atomic weights.
X Comptes Eendus, vol. xxxy. p. 278. § If Begxault’s thermal atomic weights are taken.
|| I shall in § 93 return specially to the question how often the specific heat of liquid water was compared
with that of solid bodies.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
81
with the observed ones ; this is less the case with metallic acids and oxygen salts, for
which calculation mostly gives results far too large. Garnier* drew, further, from
the above proposition the conclusion, that the atomic weight of hydrogen, chlorine, &c.
must in fact be taken only half as great as the equivalent weight ; for only by assuming
this smaller atomic weight is the mean atomic weight such that its product with the
specific heat is near 3.
In 1852 BANCALARif repeated that the specific heat of an atom of a compound body
(that is, its atomic heat) is equal to the sum of the specific heats of the individual con-
stituent simple atoms, and showed, from a series of examples (oxides, chlorides, sulphates,
and nitrates), that, according to that proposition, the atomic heats of many compounds
may be calculated in tolerable approximation with those derived from Regnault’s expe-
rimental investigations, if, for the elements which he investigated, the atomic heats
derived from his determinations be taken as a basis, that is, for oxygen (0 = 8) the
atomic heat 1'89; for chlorine (Cl=17*75) 3-21 * for nitrogen (N = 7) 3*11.
Cannizaro (in 1858$) has used the proposition, that, in the sense above taken, uni-
AC
versally -^-=a constant, for the purpose of ascertaining the value of n for the atomic
weight of different compounds, and therewith ascertaining the atomic weight of elements
which are contained in these compounds.
14. Besides those of Regnault, but few experimental determinations of the specific
heats of solid bodies have been published. Bede§ and Bystrom|1 have published inves-
tigations on the specific heat of several metals at different temperatures : both sets of
experiments were made by the method of mixtures. From the year 1845, Person**, in
his investigations on the specific heat of ice, then on the latent heats of fusion, and
their relations to the specific heats in the solid and liquid condition, has determined the
specific heat for several solid Substances, especially also for some hydrated salts. He
worked more especially by the method of mixture. He observedff , in the case of these
* Comptes Rendus, vol. xxxvii. p. 130.
f An abstract from Memorie della Accademia delle Scienze <li Torino, [2] vol. xiii. p. 287, in the Archives des
Sciences Physiques et Naturelles, vol. xxii. p. 81. I only know the contents of this memoir from this abstract.
X II Nuovo Cimento, vol. vii. p. 321. Piazza also gives a statement of this speculation in his pamphlet,
‘ Formole atomistiche et typi chimici,’ 1863. I only know this from a notice in the Bulletin de la Societe
Chimique de Paris, 1863.
§ An abstract from the Bulletin de PAcademie des Sciences de Belgique,, vol. xxii. p. 473, and the Me'moires
Couronnes par l’Academie de Belgique, vol. xxvii., appeared in the Bericht iiber die Fortschritte der Physik im
Jahre 1855, dargestellt von der physicalischen Gesellschaft zu Berlin, p. 379.
|| Abstract from the Oversigt of Stockholm Yetenskaps-Akademiens Forhandlingar, 1860, in the same Jahr-
eshericht, 1800, p. 369.
if To the experiments of Dulong and Petit on this subject, mentioned in § 3, Pouiilet’s determinations of
the specific heat of platinum at different temperatures must be added (Comptes Rendus, vol. ii. p. 782).
** Comptes Rendus, vol. xx. p. 1457 ; xxiii. pp. 162 & 366. Ann. de Chim. et de Phys. [3] vol. xxi. p. 295 ;
xxiv. p. 129 ; xxvii. p. 250 ; xxx. p. 78.
tt Peiison expressed this in 1845 (Comptes Rendus, vol. xx. p. 1457), with regard to his determinations of
N 2
82
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
salts, that their specific heats may be calculated in close approximation with those found
experimentally on the assumption that the constituents, anhydrous salt and water con-
sidered as ice, have the same specific heats in them as in the free state. By the same
method, Alluard* (in 1859) determined the specific heat of napthalene. ScHAFARixf,
lastly, has executed by the method of mixtures a series of experiments on the determi-
nation of the specific heats of vanadic, molybdic, and arsenious acids.
Quite recently (1863), PapeJ has published investigations on the specific heat of anhy-
drous and hydrated sulphates. He worked by the method of mixture, which he mo-
dified in the case of salts rich in water, by placing them in turpentine, and observing
the increase of temperature produced in the salt and in the liquid by immersing heated
copper. As a more general result, Pape finds that for hydrated sulphates of analogous
formulse, the products of the specific heats and the equivalents are approximately
equal; and further, that with sulphates containing different quantities of water, the
product of the specific heat and the equivalent increases with the quantity of water,
in sueh a manner, that to an increase of each one equivalent there is a corresponding
increase in the product.
15. In the preceding paragraphs I have collated, as far as I know them, the investiga-
tions on the specific heat of solid bodies, on the relations of this property to the atomic
weight, and on the connexion with the chemical composition of a substance. The views
which have been expressed relative to the validity of Dulong and Petit’s § and of
Neumann’s laws, and also as to the question whether the elements enter into chemical
compounds with the same specific heats which they have in the free state or with modi-
fied ones, have been various and often discordant. In this respect it may be difficult to
express an opinion which has not been already either stated or hinted at, or which at
any rate cannot be naturally deduced from a view previously expressed.
The results to which my investigations on the specific heats of solid bodies have led
me are the following : — Each solid substance, at a sufficient distance from its melting-
point, has a specific heat, which may vary somewhat Avith physical conditions (tempe-
rature, greater or less density, amorphous or crystalline conditions, &c) ; yet the variations
are never so great as must be the case if a variation in the specific heat of a body is to
the specific heat of crystallized borax and of ordinary phosphate of soda. He has subsequently published the results
of his experiments for the latter salt (Ann. de Chim. et de Phys. [3] vol. xxvii. p. 253), hut I cannot find the
number which he found for crystallized borax. * Ann. de Chim. et de Phys. [3] vol. lvii. p. 438.
t Berichte der Wiener Akademie der Wissenschaften, vol. xlvii. p. 248.
X Poggendorff’s ‘ Annalen,’ vol. cxx. pp. 337 & 579.
§ The universal validity of this law was also defended by Brehow, “ On the relation of the Specific Heat to
the Chemical Combining Weight.” Berlin, 1838. I only know this paper from the mention of it in the new
edition of Gehler’s * Physicalisches Worterbuch,’ vol. x. p. 818. It is also admitted by Manx, in his attempt to
deduce this law from the undulatory theory of heat. (1857 : Schxomixch and Witzschel’s 4 Zeitschrift fur
Mathematik und Physik,’ II. Jahrgang, p. 280) ; and by Stefan, in his investigation on the bearing of this
law on the mechanical theory of heat (1859 : Berichte der Wiener Akademie, vol. xxxvi. p. 85).
PEOFESSOK KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
83
be held as a reason for explaining why the determinations of the specific heats of solid
elements do not even approximately obey Dulong and Petit’s law, nor those of solid com-
pounds of analogous chemical constitution Neumann’s law. Neither law is universally
valid, although I have found that Neumann’s law applies in the case of many compounds
of analogous atomic composition, to which, on account of their totally different chemical
deportment, different formulas are assigned ; and even in cases in which these laws have
hitherto been considered as essentially true, the divergences from them are material.
Each element has the same specific heat in its solid free state and in its solid com-
pounds. From the specific heats to be assigned to the elements, either directly from
experimental determination, or indirectly by calculation on the basis of the law just
stated, the specific heats of their compounds may be calculated. I show the applicability
of this by a great number of examples.
In reference to this calculation of the specific heats of solid bodies I may here make
a remark. The agreement between the results of calculation and experiment is often
only approximate ; it is then natural to urge that the two ought really to agree more
closely. To that the question may be allowed : What means are there of even approxi-
mately predicting and calculating beforehand the specific heat of any inorganic or
organic solid compound when nothing but its empirical formula is given 1 to which
among the numbers OT, 0'2, 0-3 may it come nearest! The cases in which
differences exist between calculation and observation, enumerated in § 103 to 110, may
be set against this uncertainty.
My proof of the propositions given above is based on determinations made by earlier
inquirers, and on a not inconsiderable number of my own. I first describe the method
by which I worked, and then give the results which I have obtained by its means.
PAET II. — DESCRIPTION OF A METHOD OF DETERMINING THE SPECIFIC HEAT OF SOLID
BODIES.
16. I have worked by the method of mixture. It is not necessary for me to discuss
the advantages which this method has over that of the ice-calorimeter, at any rate in
requiring smaller quantities ; nor, as compared with the method of cooling, need I dis-
cuss the uncertainties and differences in the results for the same substance, which are
incidental to the use of this method, and which Regnault has detailed*.
The method of mixtures has been raised by Neumann and by Regnault to a high
degree of perfection. Although by Neumann’s method it is possible to determine more
accurately the temperature to which the body investigated is heated, Regnault’s method
allows larger quantities to be used. Regnault’s process gives the specific heats of
such substances as can be investigated by it as accurately as can at all be expected in
the determination of this property. In the case of copper and steel, it is not merely
possible to determine their specific heats by its means, but also to say whether and how
* Ann. de Chim. et de Phys. [2] vol. Ixxiii. p. 14 ; [3] vol. ix. p. 327.
84
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
far there is a difference in the first metal according as it has been heated or hammered,
and in the second, according as it is soft or hard. It may be compared with a gonio-
meter, which not only measures the angles of a crystal, but also the differences in the
angle produced by heat ; or it may be compared to a method for determining the specific
gravity of a body, by which not only this property, but also its changes with the tem-
perature may be determined. But along with such methods, simpler ones, though
perhaps less accurate, have also their value. Which method is the most convenient or
which ought to be used in a given case, depends on the question to be decided by the
experiment, or on the extent to which the property in question is constant in the sub-
stance , examined.
In regard to the relations of the specific heat of solid bodies to their atomic weight
and to their composition, Regnault’s determinations have shown that both Dulong
and Petit’s and Neumann’s law are only approximate, and that even the accuracy in
determining the specific heat which Regnault attempted, and obtained, could not show
that these laws were quite accurate.
Although the description of Regnault’s mode of experimenting is so widely known, yet
it cannot be said to have become the common property of physicists, or to have found
an entrance into the laboratories of chemists, to whom the determination of the specific
heat is interesting from its relation to the atomic weight. Very few experiments have
been made by this method other than the determinations of Regnault. The method
depends on the use of an apparatus which is tolerably complicated and takes up much
room. Each experiment requires a long time, and for its performance several persons
are required. Regnault has usually worked with very considerable quantities of the
solid substance, and in by far the majority of cases at temperatures (usually up to 100°)
which many chemical preparations, whose specific heats it is important to know, do not
bear. In the sequel I will describe a process, for the performance of which the
apparatus can be readily constructed, and for which one operator is sufficient ; by which,
moreover, the determination of specific heat can be made with small quantities of the
solid substance and at a moderate temperature. But the method as I have used it has
by no means the accuracy of that of Regnault. In § 18 I shall discuss the advantages
for which some of the accuracy which characterizes Regnault’s method is sacrificed ; but
I may here remark that the results obtained by the method which I have used are
capable of increased accuracy, provided the experiments are executed on a larger scale
and within greater ranges of temperature.
17. The principle which forms the basis of my method is as follows: — To determine
the total increase of temperature produced when a glass containing the substance to be
investigated, covered by a liquid which does not dissolve it, the whole previously warmed,
is immersed in cold water ; to subtract from the total increase of temperature that due
to the glass and the liquid in it, and to deduce from the difference, which is due to the
solid substance, its specific heat.
If, in regard to gain or loss of heat, the glass, in so far as it comes in contact
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
85
with water, is equivalent to x parts of water, if f is the weight of the liquid in it, y its
specific heat, m the weight of the solid substance, M the weight of the water in a calo-
rimeter, including the value in water of the immersed part of a thermometer and of the
calorimeter, T the temperature to which the glass and its contents have been heated
before immersion in water, and T' the temperature to which the glass sinks when im-
mersed in the water, while the temperature of the latter rises from t to t', then the
specific heat (sp. H.) of the solid substance is
TT M(f—t) — [r+fy) . (T— T)
P‘ 11 m(T-T')
In the sequel I shall discuss more specially the manner in which the individual mag-
nitudes in this equation were determined : I will first give a description of the apparatus
and method which I used*.
The glass vessel in which the substance is confined (Plate XX. a in fig. 1) is a tube of
glass, the bottom of an ordinary test-tube. In it fits, but not air-tight, a cork c, which
is pressed between two small brass plates that are screwed to a wire b. The solid sub-
stance to be investigated, in the form of thin cylinders, or in small pieces the size of a
pea, along with a liquid of known specific heat, which does not dissolve it, are placed in
the tube in such a manner that the liquid covers the solid substance, and that there is a
space between the liquid and the cork when it is inserted. The glass, when the cork is
fitted, may be suspended to the balance by the wire b. Three weighings (1) of the empty
glass, (2) after introducing the solid substance, and (3) after introducing the liquid, give
the weight of the solid substance (in) and of the liquid (f).
The heating apparatus (fig. 1) serves to raise the temperature of the glass with its
contents. The glass is dipped in a mercury-bath A near its upper edge, and retained
by a holder E. The mercury-bath, which consists of a cylindrical glass vessel, is sus-
pended by means of a triangle round the neck of the vessel in an oil-bath B, which
stands on a tripod C, and can be heated by a spirit-lamp D. A thermometer fixed
to the holder F, is also immersed in the mercury-bath.
The flame of the spirit-lamp may be regulated so that the thermometer d indicates
the same temperature for a long time $. If it may be assumed that the contents of the
glass a have also risen to this temperature, then the wire b being firmly held in the
right-hand by its hook, and the clamp of the holder E in the left, the glass a is rapidly
removed from the heating vessel to the calorimeter H (fig. 2). This is almost the only
part of the entire experiment which really requires much practice ; the transference of
* All figures on tlie Plate are one-third of the natural size.
f Fig 7 shows in section how the glass with its contents and the thermometer dip in the mercury- bath and
this in the oil-hath.
+ In order to obtain temperatures constant at about 50°, a spirit-lamp with a thin wick is used, and this is
pressed in the sheath so that the alcohol-vapour above it burns with a very small flame. The position of the
wick and the intensity of the flame may be conveniently regulated if the upper part of the wick is surrounded
by a spiral of thin copper wire whose ends project from the sheath.
86
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
the glass a from the one vessel to the other must be effected in an instant, and none of
the liquid in the glass must touch the cork.
The calorimeter H stands upon a support G (fig. 2)*, on which there is an oval metal
plate o. In this there are three depressions, in which fit the three feet of the calori-
meter (they are made of very thin hard brass wire). The calorimeter is oval-shaped,
and is made of the very thinnest brass plate. In it a brass stirrer fits, made of two
parallel plates of brass of the same thinness, which are joined below by thin wires, and
provided with a thin wire ending in a little button i, which serves as handle. The plates
of the stirrer are perforated in such a manner that the glass a and a thermometer can
be passed through them. Fig. 4 shows more distinctly the construction of the stirrer,
also the section of the calorimeter.
For the experiments, the calorimeter is always filled, as nearly as possible, with the
same quantity of waterf. The stirrer is immersed, and a thermometer f dipping in the
water gives its temperature, which is kept uniform by an upward and downward uniform
motion of the stirrer. When the tube a is brought into the water of the calorimeter, it
is fastened^ in the clamp of the holder K, which is arranged like the pincettes used for
blowpipe experiments, so that it stands on the bottom of the calorimeter, and then the
stirrer is set to work. This motion of the stirrer, and therewith of the water, must be
moderate and uniform in all experiments ; this is of some importance for the uniformity
and comparability of the experiments. The temperature indicated by the thermometer
f rises and soon attains its maximum, which continues for some time, and can be observed
with certainty. With this the experiment is concluded. The tube a can be taken from
the calorimeter, dried, and used for a new experiment.
The increase of temperature produced in the calorimeter by the tube a and its con-
tents, would be incorrectly given if the warmth of the body of the operator, who moves
the stirrer and observes the thermometer, acted on the calorimeter. This is prevented
by a glass screen g g g g, fig. 2, which is fitted in the brackets h h, and above which the
handle of the stirrer projects.
1 8. This process for determining the specific heat of solid bodies, the details of which
are more minutely discussed in the sequel, has advantages over those hitherto prin-
* In making the experiment, the actual distance between the calorimeter and the heating apparatus must be
greater than is indicated in the figure, but not so great that the glass a cannot, by a rapid motion of the arm,
be transferred from the mercury-bath to the calorimeter.
t This is most conveniently effected by laying across it a bridge with a stem directed downwards (fig. 3),
and adding water until it touches the point of the stem ; and the calorimeter, which now contains almost the
requisite quantity of water, is placed on the balance, and the filling completed by means of the dropping-flask
(fig. 8). The construction of the latter is readily intelligible : it is held by the cork between two fingers, and
by approaching the hand to the bottom of the flask water commences to drop. When the flask is not in use
the tube, which fits air-tight in the cork, is raised, so that it does not dip in the water, and thus the water is
prevented from escaping.
+ Fig. 5 shows in a section the glass a, with its contents, and the thermometer / immersed in the water of
the calorimeter.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
87
cipally used, which I will here mention. The use of the mercury-bath makes it possible
readily to produce, and maintain for any adequate length of time, any temperature de-
sirable in such experiments. The mercury-bath* shares with the air-bath the advantage
that, to the substance heated in it (in this case the tube and contents), nothing adheres
when it is removed which might influence the thermal effect in the calorimeter. It
has over the air-bath the advantage, that any body placed in it takes the tempera-
ture of the surrounding medium much more quickly through its entire mass. The
communication of heat to the solid substance is materially promoted by the circulation
of the liquid between its particles ; the time necessary for the entire contents of the
glass to become equally heated is a very short onef. Moreover this very circulation
of the liquid between the particles of the solid ensures a quicker and more uniform
transmission of the heat of the contents of the glass to the water of the calorimeter ;
the maximum temperature of this water is soon attained^, although the transmission
of the excess of temperature must take place through the sides of the glass.
* In 1848 I already used such a one for heating liquids enclosed in glass tubes, in determining their specific
heats (Poggendorff’s ‘ Annalen,’ vol. lxxv. p. 98).
t In experiments on the scale on which I made them, when the mercury-bath had once been raised to the
requisite temperature, it only required ten minutes’ immersion of the glass in the bath to impart to it the tem-
perature of the bath. A more prolonged heating was found to be useless in all cases in which I tried it. In the
experiments to be subsequently described, the heating was continued about ten minutes ; in most cases less would
have been sufficient. In Regnatjlt’s experiments (Ann. de Chim. et de Phys. [2] vol. lxxiii. p. 22), in which the
substance (in much larger quantities it is true) was heated in a space nearly surrounded by steam, a thermo-
meter placed in the substance indicated after about two hours an almost constant position (always one or two
degrees lower than the temperature of the steam) ; and then it was found convenient to continue this heating for
at least an hour, in order to see that the temperature did not change, and to be certain that the substance had
the temperature indicated by the thermometer throughout its entire mass. In Neumann’s experiments, the space
in which the substance to be heated is contained is smaller and more completely surrounded by vapour. The
time necessary for heating the substance uniformly must be smaller, and the temperature must be nearer that of
the surrounding vapour. According to Pape (Poggendorff’s ‘ Annalen,’ vol. cxx. p. 352), a thermometer placed
in the above space, if surrounded by steam for forty-five to sixty minutes, gives exactly the temperature of
this steam.
+ In several experiments I determined the time which elapsed between immersing the glass with contents
in the water of the calorimeter and its attaining a maximum. Under the circumstances, which I subsequently
give more specially, and which, as far as possible, were maintained in all experiments, this time was always less
than two minutes, if the liquid could circulate between compact pieces of the solid substance. What I have said
above justifies, I think, my not having made, in experiments with such substances, a correction for the loss of
heat which the calorimeter experiences between the moment of immersing the glass and the establishment of a
maximum temperature. In substances which form a fine powder or a porous mass, or in general in cases in which
the circulation stagnates, the maximum temperature is more slowly attained, the above loss of heat is more con-
siderable, and the numbers for the specific heats are then somewhat too small. I shall recur to this again in
enumerating the experiments in § 41 with chromium, and in § 52 with chloride of chromium. In a few cases
I have endeavoured to diminish this error, and to promote the circulation of the liquid by pressing the porous
substance into small disks. I must leave it as an open question whether more accurate results would not be
obtained for such substances if they were formed by means of a suitable cement into compact masses, and then
the thermal action of the cement thus added taken into account.
MDCCCLXV.
0
88
PROFESSOR KOPP OjST THE SPECIFIC HEAT OF SOLID BODIES.
The apparatus which I have just described is very simple. It is readily constructed;
the chief point is to have two thermometers which have been compared with each other,
one of them (f) graduated in tenths of a degree, while on the other ( d ) the tenth of a
degree can be observed with certainty. The apparatus does not require much space ;
yet, while the experiment is being made, rapid changes in the temperature of the sur-
rounding air must be avoided. One observer only is required (all the experiments
described in the sequel have been made without assistance). The experiments which I
shall communicate prove that, by means of this apparatus, the specific heat of solid
substances, even when only small quantities are taken (in most cases I worked with
only a few grammes), may be determined with an accuracy not much less than that
attained with larger quantities in more complicated processes.
19. Yet, it is true, the accuracy of the results obtained by this process appears to be
inferior to that attainable by the use of Neumann’s or of Regnault’s methods. I have
investigated many substances, determinations of which have also been made by these
physicists. I do not find that the numbers I have obtained deviate in one special direc-
tion from those which these physicists have found, which moreover sometimes differ
considerably among themselves * ; but that the certainty of the results I have obtained is
less, is shown by the fact that the results of different experiments with the same substance
agree less closely with one another than do those 'of Regnault and of Neumann.
That my determinations are less accurate is probably least due to the circumstance
that I did not use certain corrections, for instance, that I did not allow for the loss of
heat in the calorimeter between the time when the heated body was immersed and the
maximum temperature was attained f. I have endeavoured to diminish the uncer-
tainty of the results from this source by having the temperature of the water in the calori-
meter, before immersing the heated body, somewhat lower than that of the surrounding
air. I have endeavoured to ensure comparability in my results for different substances
by always operating as much as possible under the same circumstances ; that is, I
endeavoured always to produce in the water of the calorimeter the same excess of
temperature over that of the surrounding air. Without depreciating the interest and
value of such corrections, I think that their application may be omitted if them practical
importance is inconsiderable, and the increased difficulties which they necessitate pro-
portionally large. It must be considered, in reference to such corrections, how far
the accuracy, which the results obtained by their means claim, is not more apparent than
real $. And further, that these corrections, where the conditions for their application
really exist, are not considerable ; while, where they exert a considerable influence on
the result, they may be uncertain, because the suppositions made in their development
* Pape, in Poggendokee’s ‘Annalen,’ vol. cxx. p. 579, discusses the probable causes of these differences.
f Another correction, which appears to me to he more important for the experiments in question, is, that the
contents of the glass at the time at which the temperature of the water is at its maximum may he at a some-
what higher temperature. This I have approximately taken into account. Compare §§ 23 & 24.
X It is unnecessary to adduce examples where such corrections, proceeding from as comprehensive a basis as
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
89
are less applicable. But more especially can such corrections be disregarded when, as
in the case with my determinations, other circumstances diminish more materially the
accuracy of the results to be obtained.
Such circumstances in my experiments are, that I worked on a small scale in every
respect. I could only heat the solid investigated together with a liquid to 50°, and in
many cases not even to this. In Neumann’s and in Regnault’s experiments, on the
contrary, the solid was usually heated to near 100°, and the difference in temperature,
T— T' (compare § IT), obtained in the latter experiments was usually thrice as great
as in mine. In Regnault’s experiments (in Neumann’s the details are not given) the
quantity of substance taken was, on the average, twenty times as much, and the weight
of water in the calorimeter about eighteen times as much as in mine * : hence in the
latter experiments the unavoidable accidental errors of observation must be greater
than in the former.
But there is a still more important circumstance which makes the accuracy to be hoped
for from my experiments less than that to be expected from Regnault’s and Neumann’s
experiments. In the latter methods the increase in the temperature of the water of the
calorimeter is entirely, or is almost entirely produced by the solid under examination.
In my experiments, on the contrary, this increase is produced by the glass, the solid,
and the liquid in the glass. The thermal action due to the solid is only a part of the
entire thermal action observed, and if from the latter that due to the liquid and to the
glass is subtracted, all uncertainties in the assumptions as to the thermal action of the
possible, lose their significance from necessary simplifications, and tbeir practical importance becomes finally
very slight. The amount of correction is then to be pronounced as having no influence on the final result.
It is more important to take into account the following. The trustworthiness of the specific heat to be
assigned to any particular compound depends upon the certainty of the determination of the physical property,
and upon the certainty of the knowledge of the composition of the body in question ; that is, in how far this
compound corresponds to a given formula. The greatest trouble which can be taken in that determination,
the consideration of all sources of error which are possible in the physical experiment, the most complete exposi-
tion of the corrections which by developing conclusions from more or less certain assumptions may be formu-
lated in one expression, and the most conscientious application of these corrections, — all this may be paralyzed
by the' circumstance that the composition of the body in question is not, as it were, the ideal, not corresponding
accurately to the formula. The partial substitution, if even to a very small extent, of one constituent by an
isomorphous one, the attraction of water by a hygroscopic substance before and during the experiment, the
presence of some mother-liquor in a crystallized salt, the loss of some water in drying a hydrated substance, so
that this has not exactly the composition corresponding to the formula, — all these sources of error, which can
scarcely be taken into account, may easily exercise an influence on the final result, whose magnitude far exceeds
that of certain corrections applied to the physical part of the determination. It lies in the nature of the case
that in such investigations, in some cases bodies of well-known, in other cases bodies of less well-known composi-
tion are taken. I tried to be certain what substances could be considered as of definite composition and what of
doubtful composition, especially where the relations between the specific heat and the atomic weight or che-
mical composition were under discussion.
* About sixty solids have been investigated both by Regxaglt and myself; for about thirty the weights which
he used in his determinations are twenty times as much as in mine or more.
0 2
90
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
liquid and that of the glass are concentrated on the remainder, on the thermal action of
the solid substance from which its specific heat is to be deduced. The results obtained
by my method are less accurate when the residue is only a small fraction of the total
result from which it is deduced. In individual cases, where this was unavoidable, I
shall have to remark upon it.
It may be said in favour of my method that, for a number of solid substances, no
other method yet attempted is applicable either at all or with more prospect of a suc-
cessful result. But this is less important than the proof furnished by my examination
of very many substances, whose specific heat has been already determined by Neumann
and by Regnault, that the specific heat of bodies may be determined by my method
with an accuracy quite sufficient for many comparisons. But there are cases in which
it is even advantageous not to heat the solid alone, but in conjunction with a liquid, and
to bring them together into the water of the calorimeter. The chemical nature of the
solid may necessitate this ; as, for example, when it readily alters on being heated in the
air (compare § 34 in reference to amorphous boron) ; its physical structure may also
render it desirable, as for instance if the substance has a large surface as compared with
its mass, or is so porous that the thermal action due to humectation, and first observed
by Pouillet *, takes place. Regnault has shown that this may be considerable f ; he
states that for this reason the specific heat of some substances is found about too
great. He appears to have estimated this thermal action by ascertaining the increase
of temperature produced in the water of the calorimeter when the porous substance,
whose temperature is that of the water and of the surrounding air, is dipped in it. But
this action is probably far more considerable if, while heated, it is immersed in the
water, because it then contains less air confined on its surface and in its pores J, and
surface action can then act more intensely upon the liquid. The influence of this
source of error cannot be measured exactly. It is unequal in different substances. In
platinum it is small (Regnault found by his method that the specific heat of spongy
platinum did not materially differ from that of massive pieces), while it may be con-
* Ann. de Chim. et de Phys. [2] vol. xx. p. 141.
t Ann. de Chim. et de Phys. [3] vol. i. p. 133. Regnault preferred to immerse the heated porous sub-
stances, when they could be obtained in coherent pieces, directly in the water of the calorimeter. If they were
enclosed in thin tubes and immersed, the equalization of temperature proceeded too slowly. Regnault abstained
from enclosing at the same time a sufficient quantity of water in the tube to promote the circulation, because
in that case the thermal action of the solid was only a fraction of that of the water added, on which the entire
source of error falls. Regnault found also (ibid. p. 142) that in immersing anhydrous baryta, strontia, and lime
in most carefully dehydrated oil of turpentine, there is such a thermal action that no useful result is to be obtained
by his method for these oxides.
i. To the examples already known, which show what influence temperature exerts on the quantity of air
absorbed in a porous body, Regnault has added a very instructive one (Ann. de Chim. et de Phys. [3] vol.
lxiii. p. 32). If amorphous boron, formed into disks by pressure in a steel mortar, was strongly cooled and then
immersed in the water of the calorimeter (at the mean temperature), so considerable a disengagement of
absorbed air was produced, that Regnault was compelled to give up the determination of the specific heat
by this method.
PROFESSOE IvOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
91
siderable for porous charcoal (in fact Pouillet’s experiments make this probable).
This source of error is excluded in my method.
20. In order to appreciate the trustworthiness of the results arrived at by my mode
of experiment, it is important to state with what amount of accuracy the data of obser-
vation and the ancillary magnitudes were determined. I will give this statement in what
now follows.
Por observing the temperature of the water in the calorimeter I used thermometers
made by Geissler of Bonn, which the kindness of Professor Buff, Director of the Phy-
sical Cabinet in Giessen, placed at my disposal. In these thermometers the tube
consists of a fine glass thread drawn out at the lamp. The bulb is cylindrical, very
thin in the glass, and contains but little mercury. On one ( b ) 1° C. corresponds to a
length of almost 5 millims. on the scale, and on the other (r) to almost 4*5 millims.
Tenths of a degree can be read off directly on the scale, and it is easy to learn to
estimate hundredths safely. I have repeatedly compared these two thermometers,
between 7° and 24°, with two normal thermometers of my own construction, which
agree very well with each other, and on one of which a division corresponds to 0o,4878,
and the other to 0o,4341. The differences of the indications between the Geissler’s
thermometers and these could be considered as constant within those limits ; for the
differences thus observed all the readings made with the Geissler’s thermometers had
to be corrected to make them comparable with the indications of the normal ther-
mometer.
The temperature of the mercury-bath was ascertained by means of one of these
normal thermometers, and the indications of this thermometer immersed in the bath
(d in fig. 1.) corrected for the lower temperature of the mercury thread out of the
bath ; this latter temperature was given with adequate approximation by the second
thermometer, e.
21. The weight of the thin sheet-brass calorimeter, together with stirrer, was 11T45
grms.* Taking the specific heat of brass, according to Begnault, at 0-09391, the
calorimetric value in water of this mass of metal is 1 -046 grm. Considering that the
calorimeter in the experiments was not quite filled with water, but about ^th remained
empty, even after introducing the tube, I put the value in water at 0-872.
In determining the calorimetric water value of the immersed parts of the thermo-
meters r and b, the following experiments were made. The weight of water in the
calorimeter, together with the reduced weight of the metal, was 30-87 grms. When the
thermometer r heated to 330,86 was immersed, the temperature rose from 10°-73 to
10o,85 ; the immersion of the thermometer b at a temperature of 37°-53 caused a rise from
10°-61 to 10°-76. In both cases the temperature of the water was indicated by means
* At the beginning of these investigations. During their progress the calorimeter was cleaned and dried
with bibulous paper a countless number of times, so that its weight diminished by about 0-04 grm. in the
course of the experiments. In determining the weight of water used in each experiment, the weight which the
calorimeter actually had at the time was taken as basis.
92
PKOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
of the other thermometer, the reduced value of which might be neglected under these
circumstances. These experiments gave 0T6 as the reduced value of the thermometer
r, and 0T7 as the reduced value of the thermometer b. The thermometers have very
nearly the same dimensions. Hence I put the reduced value of the calorimeter (that
is, of the part of the metal concerned), of the stirrer, and of the immersed part of the
thermometer at 1*04 grm. Even if this determination is a few tenths out, it is scarcely
appreciable as compared with the quantity of water in the calorimeter. In all following
experiments this was between 25-85 and 25-95 grms.
All the subsequent determinations depend on fixing differences of weights and of
temperatures. The accuracy of the results depends on the precision with which both
kinds of magnitudes are ascertained ; and it is useless to determine the weights to ywoo
or nearer, if the differences in temperature cannot be determined more accurately than
to -200 or -3^0. I have weighed to centigrammes instead of to milligrammes, by which
the time necessary for the weighings was much shortened, and their accuracy not
materially lessened.
22. The reduced value x remained to be determined of the glasses (cylindrical tubes
of thin glass, see § 17), or, rather, of that part which was immersed in the water of the
calorimeter, the quantity of which was always the same. In the following, T is the
temperature to which the glass in the mercury-bath was heated (compare fig. 1), M the
quantity of water in the calorimeter + the reduced value in water of the other parts of
the latter, which required to be taken into account, t the temperature of the water in
the calorimeter when the glass was immersed (fig. 2), and r the temperature to which
the water became heated, and which must be considered as that to which the glass
cooled*. We have then
M(r-<)
X~ T-r
In my experiments I used three glasses, which may be called 1, 2, and 3. To ascer-
tain the reduced value of glass 1, I made the following determinations : —
Temperature of Air 15°-8.
T.
r.
t.
M.
X.
0
0
grms.
78-54
17-23
15-72
26-98
0-664
74-38
17-16
15-78
26-97
0-651
75-51
17-14
15-72
26-92
0-655
76-06
17-15
15-73
26-945
0-649
77-32
17-22
15-74
26-96
0.664
Mean .
. 0-657
* If the cork which closes the glass, and by means of the wire passing through it enables it to he handled, is
moist, incorrect and discordant values are obtained for it, owing to the evaporation of water in the empty
glass so iong as this is in the mercury rbath, and to the condensation of aqueous vapour in the glass when it is
immersed in the calorimeter.
PROFESS OE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES,
93
I subsequently made a second series of experiments to determine the reduced value
for glass 1, which gave the following results : —
Temperature of the Air 19°-9-19°-8.
T.
r.
t. .
M.
X.
0
o
o
grms.
78-50
21-32
19-93
26-99
0-656
81-86
21-47
20-03
26-98
0-643
80-42
21-43
20-02
26-98
0-645
79-77
21-42
20-03
26-935
0-642
80-14
21-51
20-12
26-955
0-639
Mean .
. 0-645
The mean of these two means, 0-657 and 0,645, gives as the reduced value in water
of glass 1, 0-651 grm.
To obtain the water value for glass 2, I made the following determinations : —
Temperature of the Air 12°-0-12°-5.
T.
r.
t.
M.
X.
0
o
o
grms.
75-87
13-53
12-43
26-94
0-475
77-05
13-46
12-31
26-96
0-488
76-71 '
13-68
12-54
26-975
0-488
75-97
13-76
12-65
26-95
0-481
78-60
13-83
12-62
26-95
0-503
Mean
. 0-487
The reduced value for glass 2 is hence = 0487 grm. This glass broke before I
made a second series of experiments to ascertain its reduced value.
I made two series of experiments to determine the reduced value of glass 3. The
first gave the following results : —
Temperature of the Air 190,3-19°-5.
T.
r.
t.
M.
X .
O
o
o
grms.
81-00
20-33
19-31
26-98
0-454
80-03
20-83
19-84
26-965
0-451
80-22
20-93
19-94
26-98
0-451
84-06
21-04
20-02
26-945
0-436
81-90
20-93
19-93
26-975
0-442
Mean . . 0-447
94
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
The second series of experiments gave the following results : —
Temperature of the Air 19°-9-19°*8.
T.
r.
t.
M.
X.
0
grms.
80-41
21-08
20-06
26-965
0-464
79-64
21-10
20-09
26-965
0-465
79-98
21-12
20T2
26-96
0-458
80-22
21T2
20-12
26-985
0-457
7953
21-10
20-12
26-965
0-452
80-52
21-13
20-14
26-96
0-450
Mean .
. 0-458
The reduced value of glass 3 = 0453 grm., the average of the mean numbers of both
series of experiments.
23. In those experiments in which a glass containing a liquid and perhaps a
solid substance is immersed, while warm, in the water of the calorimeter, it may be
asked if, when the water has become heated to a certain maximum temperature, the
contents of the glass have actually cooled to the same temperature. In earlier experi-
ments made by the method of mixture, it was at once assumed that the temperature
assumed by the water of the calorimeter after immersing the solid was actually that
also to which the immersed body sank. Neumann has taken into account that the
immersed body, when the water shows its maximum temperature, may have a somewhat
higher temperature *. Avogadro has also taken this into account f, and Regnault has
also allowed for this circumstance in the case in which the mass, immersed in the water
of the calorimeter, is a bad conductor of heat J. A correction for this fact is certainly
inconsiderable and unnecessary if the immersed body conducts heat well, and the range
of temperature through which it cools in the liquid is great. This interval of tempera-
ture was in my experiments considerably smaller than in those of Neumann and of
Regnault ; and as in my experiments the excess of heat of the contents of the glass
had to pass through its sides to the water of the calorimeter, it might be doubted
whether, when the temperature of the water was at its maximum, this temperature
could be considered as that of the contents of the glass.
I have endeavoured to answer these questions experimentally. A glass, such as was
used for holding the solid investigated and a liquid, was filled with water, and a per-
forated cork fitted, by means of which the glass could be handled, and which permitted
the introduction of a thermometer into the water within the glass. The glass filled
with water was warmed, and then placed in the calorimeter filled with water ; a thermo-
meter A, passing through the cork, showed the temperature of the water in the glass ;
* In the memoirs mentioned in § 4, Pape has also discussed and applied the correction to he made for the
above circumstance (P oggexdokfe’s •' Annalen,’ vol. cxx. p. 341).
t Ann. de Chim. et de Phys. [2] vol. lv. p. 90. ■ ± Ibid [2] vol. lxxiii. p. 26.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
95
a second, B, showed that of the calorimeter water. If the glass filled with the warmer
water is immersed in the cold water, the following circumstances are observed*. A sinks
very rapidly, while B rises more slowly ; if B shows the maximum temperature for the
water of the calorimeter (this temperature being called ^'), A gives a higher temperature
(T) for the contents of the glass. B then slowly sinks and A follows it, while the difference
between if and T' always becomes smaller. In the two following series of experiments I
have endeavoured to determine by how much, under certain conditions, the temperature
T' of the water in the glass exceeds the maximum temperature if of the water in the
calorimeter when this maximum temperature as such is observed. I obtained the
following results: the temperature of the air in the experiments was 13°-2-13°-5.
Experiments with Glass 1. Experiments with Glass 2.
T'.
t\
Difference.
T'.
?.
Difference.
15-51
15-13
d-38
15-71
15-50
0-21
14-96
14-72
0-24
15-96
15-65
0-31
16-11
15-94
0-17
15-16
14-91
0-25
15-56
15-36
0-20
14-76
14-47
0-29
14-24
14-05
0-19
14-66
14-33
0-33
15-96
15-64
0-32
15-56
15-24
0-32
A closer agreement in
the numbers
expressing the difference between T' and if is
difficult to attain,
since a
certain time
is necessary to
observe the
occurrence of the
maximum temperature, and during the time in which the thermometer B remains con-
stant, the thermometer A still sinks ; according to the moment at which the maximum
temperature is considered to be established, this difference may be obtained different,
and the smaller the later the observation is made. Moreover the magnitude of this
difference between T' and if depends on the difference between t and the temperature
of the air. I have always endeavoured to work under the same circumstances, and
especially to arrange the experiments so that the maximum temperature of the water
in the calorimeter did not exceed by more than 2° the temperature of the air f. For
these experiments and the apparatus which I used, I assumed, on the basis of the
preceding experiments, that if the water of the calorimeter had assumed its maximum
temperature t', the contents of the glass were 0o-3 higher ; that is, I put throughout T',
the temperature to which the contents of the glass immersed in the calorimeter had
fallen, =tf'4-0°-3.
24. It is a matter of course that, in introducing this correction for obtaining the tem-
* In these experiments, in order to ensure uniformity in the temperature of the water, the stirrer was kept
in continual motion, and the same process followed as in ascertaining the specific heat.
t A preliminary experiment shows how cool the water in the calorimeter ought to he. Water which is
somewhat cooler than the surrounding air, may he kept in stock for such experiments by placing it in a cylin-
drical flask covered externally with filtering paper, and standing in a dish of water, so that the paper is always
moist. To warm the water in the calorimeter, it was merely necessary, with apparatus of the dimensions I
used, to lay the hand on it for a short time.
MDCCCLXV. P
96
PKOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
perature of the contents of the glass at the time the maximum temperature has been
attained in the calorimeter, it is unnecessary to give the indications of T' in hundredths
of a degree; and since the temperature T, to which the glass with its contents was
heated in the mercury-bath, only serves to deduce the difference T — T', it is unimportant
in giving this temperature to do so in hundredths of a degree. The accuracy of the
determinations of specific heat, in so far as it depends on determinations of temperature,
is limited by the accuracy with which the difference of T— T' and t!—t are determined
(where t is the original temperature of the water in the calorimeter, and the other
letters have the meanings previously assigned to them). To have one of these differences
very accurately, while the other is much less accurately determined, avails nothing for
the accuracy of the final results. It is at once seen that in my experiments, and especially
in those of Neumann and Regnault, the hundredths of a degree have a greater signifi-
cance for the small difference tf— t, than the tenths of a degree for the great difference
T-T'.
The correction for educing the value of T', which I have just discussed, is of course
more important the smaller the difference T— T' ; for most of my experiments in which
this difference is about 30°, the significance of this correction is inconsiderable, if the con-
tents of the glass be a good conductor. I give a few numbers. The experiments given
in § 25 on the specific heat of mercury, which, by using this correction, give it at 0‘ 0335
in the mean, give it = 0-0331 if this correction is neglected, that is, T' made=^.
The fourth series of experiments, given in § 27, for determining the specific heat of coal-
tar naphtha A, give it at 0-425 when this correction is made, and at 0-420 when it is
omitted. The first series of experiments in § 33, for determining the specific heat of
sulphur, give it at 0-159 when this correction is used, and at 0-152 when it is neglected.
Whether in all such cases T' is put —t\ or=£,o+0°-3, is of inconsiderable importance.
The correction in question is inadequate if the substance in the glass is a bad conductor ;
for example, when the solid in the glass is a pulverulent or porous mass, in which the
moistening liquid stagnates (compare § 18). That, under such circumstances, the numbers
obtained for the specific heat are found somewhat too small must be remembered in
§ 41 in the case of chromium, and in § 52 in the case of chloride of chromium. Too
small numbers are also obtained, if in the experiments the maximum temperature of the
cooling water exceeds that of the air by much more than 2°. Such experiments are not
comparable with the others, for example, with those made for the purpose of ascer-
taining the ancillary magnitudes occurring in the calculation of the results ; for them this
correction is inadequate, and the loss of heat which the contents of the calorimeter ex-
periences between the time which elapsed between immersing the glass and the establish-
ment of the maximum temperature is too great. By individual examples in § 25 in the
case of water, in § 39 in the case of copper, and § 41 in the case of iron, I shall call to
mind how this source of error may give somewhat too small numbers for the specific
heat ; but I have always tried to avoid this error, since I saw its importance in my first
preliminary experiments.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
97
25. I first attempted to test my method by some experiments in which water or
mercury was placed in the calorimeter. For the specific heats of these liquids the fol-
lowing numbers were obtained, calculated by the formula
tt_M (t' — t)—X (T — T')
P* /(T-T')
in which the signification of f is manifest from what follows, that of the other letters
from what has been given before.
In the experiments in which a readily vaporizable liquid was contained in the glass,
such as water, or coal-tar naphtha, a sensible formation of vapour took place, although
the temperature did not exceed 50°. If the glass containing the liquid was heated
in the mercury-bath (compare fig. 7), vapour was formed in the empty space below
the cork which served as stopper; if the glass was then brought into the water of
the calorimeter, this vapour condensed and settled partially on the stopper. The
stopper did not act materially on the water of the calorimeter (see fig. 5). The
quantity of liquid in the glass which acted directly on the water of the calorimeter,
decreased somewhat in each experiment ; but this decrease is very inconsiderable. In the
following experiments y denotes first the weight of the liquid in the glass at the com-
mencement of the experiment, and at last its weight at the end of the experiments, that
* is, after subtracting the liquid which had vaporized and condensed on the stopper.
After the end of the experiment the stopper was dried to remove the liquid, and by
another weighing of the glass, together with its contents and stopper, the weight of the
liquid still contained in the glass was obtained. The decrease of weight of the liquid
in the glass was always found to be inconsiderable, and might without any harm have
been neglected ; for the last experiment of a series I have always taken the diminished
weight of the liquid into account, but for those between the first and the last I have
neglected the diminution of the weight of the liquid in the glass. What I have here
said explains a remark of frequent subsequent use, “ after drying the stopper.” In re-
ference to the influence of the formation of vapour on the accuracy of the results obtained
for the specific heat of the individual substances, compare §38.
Two series of experiments in which water was contained in the glass, gave the fol-
lowing results for the specific heat of this liquid : —
Experiments with Glass 1. Temperature of the Air 19o,0.
T
T'.
t\
45*2
20-9
20-62
46-6
21-2
20-92
47-4
21-3
20-96
t. M.
o grms.
16- 83 26-945
17- 03 26-935
17-03 26-965
* After drying the stopper.
/•
sp. H.
grms.
grin.
3-43
0-651
1-035
1-013
3-42*
0-997
P
q
98
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Experiments with Glass 3. Temperature of the Air 19°*0.
T.
T'.
t'.
t.
M.
/•
X.
sp. H.
O
0
O
o
grms.
grms.
grm.
46*8
21*1
20*76
17*03
26*95
3*445
0*453
1*004
46*8
21*1
20*83
17*12
26*985
0*999
47*0
21*2
20*93
17*22
26*935
3*435*
55
0*996
The value found for the specific heat of the contents of the glass comes very near the
number 1, assumed for the specific heat of water f.
Determinations in which mercury was contained in the glass gave the following results
for the specific heat of the contents of the glass.
Experiments with
Glass 1.
Temperature of the Air 13°*8-14
°*4.
T.
T'.
a.
t.
M.
/•
X .
sp. H.
o
51*1
16*8
16*50
13*41
grms.
26*945
grms.
53*015
grm.
0*651
0*0335
48*5
16*8
16*48
13*64
26*95
55
55
0*0333
45*2
16*5
16*20
13*63
26*965
55
55
0-0333
Experiments with Glass 2.
Temperature of the Air 130,8-140*
4.
T.
T'.
t'.
t.
M.
/•
X.
sp. H.
50*0
O
171
16*79
13*74
grms.
26*935
grms.
60*015
grm.
0*487
0*0335
4
45*6
16*7
16*41
13*72
26*935
55
55
0*0337
The mean of these five determinations gives 0*0335 for the specific heat of mercury,
in accordance with the results found by other observers for this metal (0*0330 between
0° and 100°, Dulong and Petit; 0*0333, Regnault).
26. For the liquid which is to be placed in the glass along with the substance whose spe-
cific heat is to be investigated, I could in many cases use water ; but many substances, the
* After drying the stopper.
t In § 24 it was mentioned that the numbers obtained for the specific heat of the contents of the glass are
somewhat too small, if the maximum temperature of the water in the calorimeter, t', exceeds the temperature of
the air by much more than 2°. As an example I give the following determinations, in which the glass used
contained water.
Experiments with Glass 1. Temperature of the Air 13°-5-13°-8.
T.
T'.
t'.
t.
M.
/-
X.
sp. H.
0
0
o
o
grms.
grms.
grm.
46-5
18-1
17-81
13-64
26-94
3-40
0-651
0-976
43-9
16-7
16-38
12-33
26-955
»
»
0-989
Experiments with Glass 2.
Temperature of the Air 13°-5-13°*8.
T.
T'.
t'.
t.
M.
/•
X.
sp. H. t
O
O
0
0
grms.
grms.
grm.
49-1
18-3
18-03
13-37
26-94
3-66
0-487
0-981
47-6
18-3
18-04
13-66
26-99
„
„
0-969
47-0
17*5
17-22
12-73
26-97
3-65*
„
0-991
* After drying the stopper.
PEOFESSOB KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
99
determination of which is important, dissolve in. water, and hence I had to use a different
liquid. Coal-tar naphtha has. the advantage that it is a mobile liquid, does not dissolve
most salts, and does not resinify in contact with the air ; but besides the disagreeable
odour, with continuous working, respiring air charged with its vapour appears to act
injuriously on the organs of the voice. As compared with water, coal-tar naphtha has
the disadvantage, that its specific heat must be specially determined, and any possible
uncertainty in this is transferred to the determination of the specific heat of the solid
substance ; but the thermal action of a given volume of naphtha is only about ^ that of
the same volume of water*; and in experiments in which the thermal action of a solid
substance is determined, along with that of the necessary quantity of liquid which is
contained with that substance in a glass, the thermal action due to the solid is a larger
fraction of the total if coal-tar naphtha is used than if water is the liquid, which is a
favourable circumstance in the accurate determination of specific heat. As it was more
especially important for me to obtain comparability in the results for specific heat, I
have, for a great many substances which are insoluble in water, and for whose investi-
gation water might have been used, also employed coal-tar naphtha. Water was used
for a few substances which are soluble in coal-tar naphtha (sulphur, phosphorus, ses-
quichloride of carbon, for instance). Several substances I determined both with water
and with naphtha ; the results thus obtained agree satisfactorily. To the question as to
whether any possible change in the specific heat of naphtha with the temperature can
be urged against the use of this liquid, I shall return in § 29.
27. The coal-tar naphtha A which I principally used in the subsequent experiments
was prepared from the commercial mixture of hydrocarbons Gn H2„_6, by purifying it by
means of sulphuric acid, treating the portion which distilled between 105° and 120°
with chloride of calcium for six days, then again rectifying it, and collecting separately
that which passed between 105° and 120°. This liquid had the specific gravity 0-869
at 15°; in determining its specific heat I made four series of experiments, two at first
when I was engaged on experiments in which I used this naphtha, and two towards
the end.
I. — Experiments with Glass 1. Temperature of the Air 12°T-12°-9.
T.
T'.
f.
t.
M.
/•
X .
sp. H.
O
o
0
o
grms.
grms.
grm.
46-1
13-8
13-51
11-24
26-99
2-875
0-651
0-433
48-6
14-0
13-71
11-24
26-945
2-875 f
55
0-443
45-5
14-1
13-83
11-59
26-97
2-975$
55
0-439
45-3
14-3
14-01
11-80
26-94
2-970 f
55
0-428
Mean . . . 0-436
* The specific heat of the coal-tar naphtha A, with which I made most of my experiments, is 0-431, and its
specific gravity at 15°=0869.
f After drying the stopper.
After adding some; naphtha.
100
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
II. — Experiments with Glass 2. Temperature of the Air 12°T-12°-7.
T.
T'.
t'
t.
M.
/•
x.
sp. H.
49-0
13-8
13-53
11-02
grms.
26-955
grms.
3-28
grm.
0-487
0-438
45-9
14-1
13-83
11-50
26-93
3-48*
55
0-427
43-3
14-2
13-86
11-73
26-95
55
0-427
46-6
14-5
14-23
11-85
26-95
3-475 f
5 5
0-435
Mean
0-432
III . — Experiments
with Glass
1. Temperature of the Air 16°
•7.
T.
T'.
t'.
t.
M.
/•
so.
sp. H.
51°-4
18-6
18*32
16-02
grms.
26-98
grms.
2-895
grm.
0-651
0-429
51-5
18-4
18-06
15-73
26-97
„
55
0-431
51-5
18-4
18-14
15-81
26-985
„
55
0-431
51-0
18-5
18-22
15-93
26-96
2-88f
55
0-434
Mean
0-431
IV . — Experiments
with Glass
3. Temperature of the Air 16°
•7.
T.
T'.
t'.
t.
M.
/•
X.
sp. H.
0
51-7
18-7
18-43
16-22
grms.
26-935
grms.
3-195
grm.
0-453
0-423
50-7
18-6
18-32
16-14
26-935
55
„
0-431
50-7
18-6
18-27
16-13
26-95
55
55
0-421
50-2
18-6
18-26
16-14
26-93
3-18 f
55
0-426
Mean
0-425
The average of the means of these four series of experiments, 0-436, 0-432, 0-431,
0-425, gives 0-431 as the specific heat of the coal-tar naphtha A between 14° and 52°;
this value is taken in calculating the experiments in the following section.
28. If it were only a question as to the determination of the specific heat of this
naphtha, the method described in the preceding might be advantageously replaced by
another. For by this method the specific heat of the liquid must be found somewhat
too great, owing to the fact that in the empty space in the glass under the stopper a dis-
tinct quantity of vapour is formed, which condenses when the glass is dipped in the
water of the calorimeter (compare § 25). Direct experiments J, in which this forma-
tion of vapour was almost entirely avoided, have shown that the method used for the
previous determinations, that is, the use of glasses for heating the liquid in which a
* After adding some naphtha. t After drying the stopper.
J I determined the specific heat of coal-tar naphtha A, using a glass in which only very little vapour could
form above the heated liquid. This glass (which I used in experiments for the determination of the specific
heat of liquid compounds) had a narrow neck, and was filled so that there was very little space in which
vapour could form; the calorimetric value of this glass, in so far as it was immersed in the water of the
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
101
relatively considerable space above the liquid remains empty, gives the specific heat of
readily vaporizable liquids somewhat too high, but that at the same time this influence
of the formation and condensation of vapour is very small in the conditions under which
I worked*. — The number 0-431 obtained in the previous determinations expresses the
thermal action due to the cooling of 1 grm. naphtha A through 1° in my experiments,
which thermal action depends to by much the greatest extent on the specific heat of this
liquid, and only to a very small extent on the condensation of the previously formed vapour.
In calculating the experiments communicated in the third section, that number is taken
as the expression for the thermal action of naphtha, which is put as proportional to the
weight of the latter. This is, strictly speaking, not accurate, in so far as the thermal
action arising from condensation of vapour only depends on the magnitude of the empty
space and the temperature, and not on the quantity of naphtha in the glass. But the
small possible inaccuracy due to this cause in my experiments is not to be compared
with other uncertainties. The manner in which I have taken into account the naphtha
contained in the glass corresponds most accurately to the actual conditions of the expe-
riment, when this thermal action is most considerable (only naphtha in the glass) ; and
if my mode of calculation less satisfies these conditions (less naphtha in the glass), the
entire amount is less considerable, and the influence of that which might be missed in
that calculation, a vanishing quantity.
29. My experiments have been made at very different temperatures. The tempe-
rature of the air was often something under 10°, sometimes above 20°. These numbers
represent the limits to which the liquid in the glass, together with the solid substance
cooled in the calorimeter. In most experiments I heated the glass with its contents to
about 50°, in some cases not so high. Now, for the various intervals of temperature
within which the liquid in the glass cooled, can its specific heat be assumed to be
always the samel For water this may be done, and for coal-tar naphtha I did not
calorimeter (comp. fig. 6), was = 0-688 grm. A series of experiments in which this glass was used to
determine the specific heat of the naphtha A gave the following results : —
Temperature
of the Air 15°-5-
-15°-6.
T.
T'.
t'.
t.
M.
f.
X.
sp. H.
O
Q
O
grms.
grms.
grm.
52-5
17-8
17-53
14-93
26-945
3-205
0-688
0-415
49-6
17-4
17-13
14-73
26-955
„
„
0-412
50-9
17-6
17-29
14-83
26-96
„
„
0-407
50-5
17-6
17-26
14-83
26-975
„
„
0-407
51-6
17-7
17-38
14-84
26-985
„
„
0-416
50-9
17-8
17-47
15-03
26-94
„
„
0-405
Mean . . . 0-410
* This is seen from the experiments on water communicated in § 25, and from the subsequent determinations
in the next section, in which water was contained in the glass along with the solid substance.
102
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
doubt it while engaged in my experiments. I first, when they were finished, became
acquainted with Regnault’s * investigations on the specific heat of liquids at various
temperatures; according to these experiments the specific heat of some liquids con-,
siderably increases with the temperature. I have not directly investigated coal-tar
naphtha in this respect, but it is probable that the specific heat of this mixture of
hydrocarbons Gn H2 n_6, alters but little with the temperature, and it is certain that this
change is without influence on the accuracy of my determinations of the specific heats
of solid substances. Regnault’s experiments f , made by the method of cooling, show no
change for benzole, €e He, between 20° and 5°, while there is a distinct change in the
case of alcohol. For pure benzole % I found the specific heat by the method of mix>
ture to be 0-450 between 46° and 19°; Regnault § found it between 71° and 21° to
be 0-436. These numbers, obtained with different preparations, are not indeed com-
parable for a decision of the question just discussed, but they render improbable a com
siderable increase in the specific heat of benzole with the temperature. What I more
especially lay weight upon is this : the specific heats of solids which I have determined
at various temperatures, by their agreement with the numbers previously found by
others, do not indicate any influence of a change of specific heat of naphtha with the
temperature.
30. My stock of the naphtha, discussed in § 27, was used before I had investigated all
the solid substances, for which a determination of the specific heat appeared necessary.
Another quantity of the same coal-tar naphtha was subjected to the same treatment as
indicated there, and the portion passing over between 105° and 120° used for the
remainder of the experiments. To ascertain the specific heat of this naphtha B, I made
the four following series of experiments : —
I. — Experiments with Glass 1. Temperature of the Air 18°-l-18°-3.
T.
T'.
i.
t.
M.
/•
X.
sp. H.
O
O
0
0
grms.
grms.
g™.
51-5
19-6
9-33
17-22
26-96
2-70
0-651
0-419
52-7
19-9
19-64
17-49
26-95
59
55
0-413
50-5
19-8
19-54
17-51
26-99
0-420
49-9
20-0
19-73
17-75
26-995
2-695 ||
59
0-422
Mean . . . 0-418
* Relation des experiences .... pour determiner les lois et les donnees physiques necessaires au calcul des
machines a feu, vol. ii. p. 262 (1862).
t Ann. de Chim. et de Phys. [3] vol. ix. pp. 336 & 349.
£ Poggendorff’s ‘ Annalen,’ vol. lxxv. p. 107. § Relation, etc vol. ii. p. 283.
|| After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES. 103
II. — Experiments with Glass 3. Temperature of the Air 18°T-18°-3.
T.
T'.
t\
t.
M.
/.
X.
sp. H.
51-4
19-7
19-36
17-32
grins.
26-94
grms.
3-085
grm.
0-453
0-415
51-5
19 9
19-63
17-56
26-965
55
0-426
49-1
19-9
19-61
17-73
26-955
55
«
0-416
50-5
20-1
19-82
17-86
. 26-98
3*08 *
0-418
Mean
• - -
0-419
III.-
—Experiments with
Glass 1.
Temperature of the Air 17°-8-18°-3.
T.
T'.
t'.
t.
M.
/•
X.
sp. H.
52-2
19-8
19-49
17-27
grms.
26-97
grms.
2-80
grm.
0-651
0-427
50-6
20-0
19-73
17-64
26-96
59
„
0-425
51-2
20-2
19-92
17 82
26-98
55
0-420
51-3
20-2
19-86
17-76
26-99
95
??
0-418
50-4
20-2
19-86
17-85
26-95
2-785 *
55
0-410
Mean
0-420
IV. — Experiments with Glass 3. Temperature of the Air 18°
■4. .
T.
T'.
t'.
t.
M.
/•
X.
sp. H.
50-2
19-7
19-43
17-33
grms.
26-96
grms.
3-31
grm.
0-453
0-424
50-1
20-1
19-77
17-66
26-99
55
95
0-416
52-5
20-2
19-87
17-65
26-96
55
59
0-423
50-1
20-1
19-83
17-82
26-95
55
55
0-409
51-4
20-2
19-93
17-82
26-97
3-29 *
55
0-417
Mean
0-418
The average of the means of these four series of experiments, 0-418, 0-419, 0*420, 0-418,
gives 0-419 for the specific heat of coal-tar naphtha B between 20° and 50°.
In the preceding method of experiment, whether water or naphtha of the kind
described is contained in the vessel, a temperature much higher than 50° cannot be
employed; for otherwise the quantity of liquid evaporating and condensing on the
stopper becomes far too considerable. Perhaps with hydrocarbons of higher boiling-
points higher temperatures might be ventured upon: I have no experiments on this
subject.
PART III.— DETERMINATION OF THE SPECIFIC HEAT OF INDIVIDUAL SOLID SUBSTANCES.
31. By the method whose principle and mode of execution have been discussed in the
preceding, I have determined the specific heat of a large number of solid substances. I
* After drying the stopper.
MDCCCLXV.
Q
104
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
should have liked to include a still larger number of bodies in my investigations ; but
a limit was put by the straining of the eyes from constant reading of finely divided
scales, and by the injurious action which the long-continued working with coal-tar
naphtha produces.
My crystallographic collection furnished me with much material for investigating the
specific heat of both naturally occurring and artificially prepared substances, but for
much more I have to thank others. By far the greater part of the chemical prepara-
tions investigated ! obtained from the Laboratory of the University of Giessen, through
the kindness of the Director, Professor Will, and of the assistants, Professor Engelbach,
to whom my thanks are especially due, Drs. Korner and Dehn. Professor Wohler, of
Gottingen, placed a number of chemical preparations at my disposal. Professor
Bunsen, of Heidelberg, has helped me to the investigation of some rubidium-com-
pounds. Platinum and iridium I have been furnished with by M. Her^eus, the pro-
prietor of the well-known platinum-manufactory in Hanau. I have had a very large
number of minerals from the mineral collection of the University of Giessen,
through the kindness of the Director, Professor Knop; and to obtain the necessary
quantity of dioptase, Professors Blum of Heidelberg, and Dunker of Marburg, have
contributed.
32. The signification of the letters in the statement of the following experiments
and their calculation is clear from § 17 ; in reference to the value of the numbers for
M, compare § 21, for x § 22, for T' § 23, for y § 27 and § 30.
It would require too much space always to give the comparison of my results with
those of other observers. I can only do this in individual cases where there are con-
siderable differences and their discussion is of importance. For other substances, where
there are recent observations by trustworthy observers, the Tables in § 82 to § 89 give
data for comparison.
33. Sulphur: pieces of transparent (rhombic) crystals from Girgenti. I made three
series of experiments with this substance.
I.—
Experiments with Water. Glass 1.
Temperature of the Air 13°-2.
T.
O
T'.
O
t'.
o
t.
M.
grms.
m.
grms.
/•
grm.
y*
sc.
grm.
sp. H.
45-8
15-5
15-24
11-74
26-95
4-16
1-765
1-000
0-651
0-168
46*0
16-2
15-93
12-52
26-935
55
55
55
55
0-160
45-2
16-0
15-73
12-42
26-945
55
55
55
0-153
45-8
16-4
16-05
12-74
26-96
55
1-75*
55
Mean
55
0-153
0-159
* After drying the stopper : compare § 25.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
105
II. — Experiments with Water. Glass 2. Temperature of the Air 13°*2.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
O
O
0
0
grins.
grms.
grms.
grin.
45*8
16*4
16*07
12*36
26*96
4*815
2*09 1*000
0*487
0*171
47*3
16*6
16*33
12*46
26*95
33
55 5?
33
0*170
44*1
16*5
16*15
12*74
26*925
33
99 55
33
0*156
45*1
16*6
16*28
12*77
26*96
33
2*07* „
Mean
33
0*159
0*164
Both these series of determinations are from the time when I first worked at this
subject. Towards the end, when I had acquired tolerable readiness, I made a third
series, which agreed very closely with the results previously obtained.
III. —
-Experiments with Water. Glass 3.
Temperature of the Air 17°*2.
T.
T.
o
t'.
0
t.
o
M.
grms.
m.
grms.
/•
grms.
y-
CC.
grm.
sp. H.
43*7
19*1
18*83
15*79
26*99
4*92
2*065
1*000
0*453
0*166
43*5
19*1
18*84
15*84
26*97
33
33
33
33
0*162
43*3
19*2
18*92
15*92
26*94
33
33
33
0*170
43*1
19*2
18*87
15*93
26*98
33
2*05 *
33
Mean
33
0*166
0*166
Taking the mean of the means obtained in the three series of experiments, 0T59,
0T64, 0T66, we obtain 0T63 as the specific heat of rhombic sulphur between 17° and
45°. By the method of cooling, Dulong and Petit found the specific heat of sulphur
at the mean temperature to be 0T88 ; Neumann found 0*209 by the method of
mixture; for sulphur which had been purified by distillation, fused and cast in rolls,
Begnault found f the specific heat between 14° and 98° to be 0*2026. In these expe-
riments a development of heat depending on a change from amorphous sulphur into
rhombic-crystallized appears to have cooperated, and to have caused the circumstance
observed by Begnault, that after immersing the heated sulphur in the water of the
calorimeter, the maximum temperature was only set up after an unusually long time.
Sulphur which has solidified after being melted, usually contains an admixture of
amorphous sulphur, the greater the more the melting-point has been exceeded, which at
the ordinary temperature passes slowly, at 100° more rapidly, into crystallized, accom-
panied by disengagement of heat. The transformation of the sulphur set up by the
heating, and continued in the water of the calorimeter, brought about this slow appear-
ance of the maximum temperature, and made the specific heat appear too great ; for
Begnault’s subsequent determinations J, also made between 97° and 99° and the mean
temperature, gave it considerably less: 0*1844 for freshly melted sulphur (in which
* After drying the stopper.
t Ann. de China. et de Phys. [2] vol. lxxiii. p. 50. Ibid. [3] vol. ix. pp. 326 & 344.
Q 2
106
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
superfusion had been avoided P) ; 0-1803 for sulphur which had been melted two months ;
0*1764 for what had been melted two years (and which had then given 0-2026) ; 0-1796
for sulphur of natural occurrence. The difference between the latter result and my
own doubtless depends, partially at least, on the fact that Regnault’s determination was
made between 14° and 99° (the latter of which temperatures is very near the melting-
point of rhombic sulphur) ; mine was made between 17° and 45° *.
Tellurium : crystalline pieces f .
Experiments with Naphtha A.
Glass 3. Temperature of the Air 18
°*6-19°v
T.
T'. t'. t.
M. m.
/• y-
■ X.
sp. H.
o
o o o
grms. grms.
grm.
grm.
51-8
20-4 20-07 17-96
26-93 10-80
1-93 0-431
0-453
0-0486
51-3
20-3 20-02 17-93
26-98
35 33
33
0-0495
51-5
20-7 20-36 18-33
26-93
33 33
„
0-0454
51-0
20-7 20-43 18-43
26-955 „
1-91$
33
0-0466
Mean
0-0475
34. Boron. — I have made some experiments with this substance, which have some
interest for the question whether this body has essentially different specific heats in its
different modifications ; but the results are not very trustworthy, owing to the spongy
nature of the amorphous boron and the doubtful purity of the crystallized variety.
The amorphous Boron § which I investigated was pressed in small bars, and had stood
several days in vacuo over sulphuric acid.
Experiments with Naphtha A. Glass 1. Temperature of the Air 17o"0-17o-2.
T.
o
T'.
o
o
t.
o
M.
grms.
m.
grm.
/•
grms.
y-
X .
grm.
sp. H.
49-0
18-7
18-73
16-36
26-955
1-52
2-515
0-431
0-651
0-246
48-1
18-6
18-55
16-23
26-965
99
99
99
99
0-254
48-0
18-6
18-64
16-33
26-95
99
99
99
99
0-252
47-9
18-7
18-72
16-42
26-95
99
2*49 J
99
Mean
99
0-262
0-254
Even if the results of the individual experiments agree tolerably with each other they
are not very trustworthy ; for the quantity of boron (only 1^ grm.) is very small, and
the amount of heat due to the boron is a very small part of the total (comp. § 19).
Yet I do not consider the result of the above series of experiments (that between 18°
and 48° the specific heat of amorphous boron is about 0-254) as being very far from
* There is nothing known certainly as to whether the different modifications of sulphur have essentially
different specific heats. Marchand and Scheerer’s experiments on brown and yellow sulphur made by the
method of cooling, compare in Journal fiir Prakt. Chemie, vol. xxiv. p. 153.
f “ Obtained from Yienna, and obviously distilled.” — Wohler.
+ After drying the stopper.
§ “ Prepared from boracic acid by sodium, and treated with hydrochloric acid.” — Wohler.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
107
the truth. There are no considerable accidental errors of observation in these experi-
ments, to judge from their agreement with one another. Of the constants for calcu-
lating the experiments, x and y must be taken into account in regard to any possible
uncertainty. It has been assumed that #=0‘615 and ^=0-431 ; if we took #=0*63
and y=0*41, the specific heat as the mean of four experiments would be =0*30 ; if x
were 0-67 and y 0*45, the specific heat would be 0*21. But from what has been com-
municated in § 22 and § 27 in reference to the determination of x and y, it cannot be
assumed that any possible uncertainty in reference to these values can reach either of
the above limits. It can be assumed with the greater certainty that the specific heat of
amorphous boron is between 0*2 and 03 and nearly 0*25, because x and y could not
simultaneously both be found too great or too small (if x had been too small y would
have been too great, and vice versd).
Crystallized Boron *.
Experiments with Naphtha A. Glass 3. Temperature of the Air 18°*9-18°*7.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
O
0
0
o
grms.
grms.
gnn.
grm.
50*9
20*8
20*52
18*53
26*94
2*82
1*53 0*431
0*453
0*237
51*3
20*8
20*52
18*52
26*975
55
55 55
55
0*233
51*5
20*8
20*53
18*53
26*985
n
55 55
55
0*229
51*4
20*8
20*46
18*43
26*99
55
l*52f „
Mean
55
0*222
0*230
Hence the specific heat of the crystallized (adamantine) boron investigated is 0*230
between 21° and 51°; it is pretty near that found for amorphous boron, 0*254. Reg-
nattlt found J (between 98° and 100° and the mean temperature) 0*225 for a specimen of
crystallized boron prepared by Rousseau; 0*257 for one prepared by Debray; 0*262
for one obtained from Deville; and 0*235 for a specimen of graphitic boron prepared
by Debray. The specific heat of amorphous boron could not be determined by Reg-
nault’s method, because, when heated to 100° in air, it partially oxidizes into boracic acid
with disengagement of heat (three experiments, in which the quantity of boracic acid
formed was determined, and its specific heat, but not the thermal action due to the forma-
tion of hydrated boracic acid in immersion in water allowed for, gave respectively 0*405,
0*348, and 0*360, which numbers Regnault does not consider as even approximately re-
presenting the specific heat of amorphous boron), and when greatly cooled disengages a
quantity of air when immersed in warmer water, which renders the results uncertain.
* “Made in Paris, probably by Rousseau, and doubtless by melting borax with aluminium. To conclude
from its external appearance, it probably contained some aluminium and carbon : compare the analysis in
Ann. der Chem. und Pharm. vol. ci. p. 347.” — Wohlek.
t After drying tbe stopper.
+ Ann. de Chim. et de Pbys. [3] vol. lxiii. p. 31.
108
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
35. Phosphorus. — I have only made a few determinations with ordinary yellow phos-
phorus, which was cast in sticks.
Experiments with Water. Glass 1. Temperature of the Air 10o,9.
T.
T'.
t'.
t.
M.
m.
/•
y-
X m
sp. H.
O
o
0
o
grms.
grms.
grms.
grm.
38-8
13-5
13-20
10-05
26-95
3-075
2-065
1-000
0-651
0-208
33-8
12-9
12-62
10-03
26-97
„
„
,,
55
0-204
35-5
13-2
12-91
10-17
26-93
55
2-06*
J?
55
0-195
Mean
0-202
The specific heat of yellow phosphorus, as deduced from these determinations, is
somewhat greater than that found by Regnault, doubtless because in my experiments
the upper limit of temperature, T', was nearer the melting-point of phosphorus, 44°.
Compare § 82.
Antimony. — Purified by Liebig’s method ; crystalline pieces.
I. — Experiments with Naphtha A. Glass 2. Temperature of the Air 14°-7.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
O
o
0
o
grms.
grm.
grm.
46-4
16-0
15-65
13-42
26-945
12-245
1-925 0-431
0-487
0-0539
44-9
15-9
15-64
13-54
26-98
5>
55 55
55 %
0-0520
44-2
15-8
15-53
13-52
26-96
55
1-91* „
Mean
'55
0-0496
0-0518
II. — Experiments with Water. Glass 1. Temperature of the Air 15°
•8-16°-l.
T.
T'.
t\
t.
M.
m.
/• y-
X .
sp. H.
0
o
o
o
grms.
grms.
grms.
grm.
45-0
17-9
17-60
14-22
26-945
11-835
2-095 1-000
0-651
0-0519
45-1
17-9
17-64
14-25
26-96
55
55 55
55
0-0519
45-0
17-9
17-64
14-25
26-965
55
55 55
55
0-0530
45-4
18-1
17-76
14-34
26-955
”
2-085* „
Mean
51
0-0542
0-0528
From these determinations, the average of the means of both series of determinations,
0-0518 and 0-0528, the number 0-0523 is the specific heat of antimony between 17°
and 45°.
Bismuth. — Purified by melting with nitre, and cast in small bars. In the case of
this metal also, I have made a series of determinations with coal-tar naphtha in the glass,
and one with water.
After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
109
I. — Experiments with Naphtha A. Glass 3. Temperature of the Air 180,9-180,8.
T.
50-8
T'.
20-6
t'. .
20-33
t.
18-33
M.
grms.
26-99
m.
grms.
20-71
/•
grm.
1-70
y-
0-431
x. sp. H.
grm.
0-453 0-0291
50-3
20-7
20-42
18-43
26-955
99
99
„
„ 0-0302
50-1
20-6
20-33
18-37
26-955
99
99
99
0-0292
50-9
20-7
20-40
18-42
26-955
99
1-685
*
99
„ 0-0284
Mean
. . . 0-0292
II. — Experiments with Water. Glass 1. Temperature of the Air 16°-7-16°-8.
T.
45-2
T'.
18? 7
t'.
18-44 .
t.
15-25
M.
grms.
26-97
m.
grms.
19-43
/-
grm.
1-995
1-000
x. sp. H.
grm.
0-651 0-0309
45-5
18-9
18-57
15-36
26-965.
99
„
99
,. 0-0313
45-0
18-9
18-64
15-47
26-975
99
99
99
„ 0-0324
46-0
181
18-82
15-56
26-99
99
1-985*
99
Mean .
„ 0-0327
. . 0-0318
From these determinations we get for the specific heat of bismuth between 30° and
48° the number 0-0305.
36. Carbon. — It is known how different are the numbers obtained for the specific heat
of carbon in its different forms. I have determined the specific heat for comparatively
only a few of the modifications of carbon — for gas-carbon, for natural and artificial gra-
phite. Before the experiment each of these substances was strongly heated for some
time in a covered porcelain crucible, and then allowed to cool, and immediately trans-
ferred into the glass for its reception, and, after weighing, naphtha poured over it.
Gas-carbon from a Paris gas-works ; very dense, of an iron-grey colour, and left very
little ash when calcinedf. It was used in pieces the size of a pea, and two series of
experiments were made.
* After drying the stopper.
t This carbon, as well as the above-mentioned varieties of graphite, was analyzed in the Laboratory at
Giessen by Mr. Hubek. The gas-carbon gave, when placed in a platinum boat and burned in a stream of
oxygen,—
I.
II.
III.
IV.
V.
Carbon
. . 97-19
98-25
97-73
98-08
98-55
Hydrogen . '.
. . 0-53
0-15
0-68
0-37
1-00
Ash
. . 0-61
0-62
0-73
0-23
0-69
98-33
99-02
99-14
98-68
100-24
110
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
I. Experiments with Naphtha A. Glass 1. Temperature of the Air 18o,9-190,2.
T.
T'.
t'.
t.
M.
m.
/•
y •
X.
sp. H.
O
O
o
0
grms.
grms.
grm.
grm.
52*9
20*8
20*53
18*13
26*955
3*135
1*825
0*431
0*651
0*184
52*6
20*9
20*63
18*26
26*98
„
33
„
0*185
51*7
20*7
20*42
18*06
26*97
33
35
33
„
0*196
52*4
20*9
20*58
18*23
26*98
33
1*805*
33
J?
0*186
Mean . . . 0T88
II. — Experiments with Naphtha A. Glass 3. Temperature of the Air 20°*5-20°*8.
T.
T'.
t'
t.
M.
m.
/•
y-
X.
sp. H.
52*6
22*6
22*33
20*23
grms.
26*985
grms.
3*345
grm.
1*935
0*431
grm.
0*453
0*180
52*2
22*5
22*23
20*14
26*985
33
33
33
33
0*183
52*3
22*5
22*20
20*12
26*965
33
33
33
33
0*179
52*5
22*6
22*31
20*22
26*955
1*91*
33
33
0*182
Mean . . . 0*181
These determinations give as the average of the means of both sets of experiments
the number 0*185 as the specific heat of gas-carbon between 22° and 52°.
Natural graphite from Ceylon. Left very small quantities of ash when calcinedf.
I. — Experiments with Naphtha A. Glass 3. Temperature of the Air 18°*9-19°*2.
T.
T'.
t'.
t.
M.
o
o
o
0
grms.
51*4
20*8
20*48
18*13
26*975
51*4
20*8
20*51
18*13
26*99
51*8
20*8
20*54
18*15
26*975
52*0
20*8
20*54
18*13
26*99
* After drying the stopper,
t In Mr. Hubeb’s analyses this substance was
m.
/• y-
X .
sp. H.
grms.
grms.
grm.
4*025
2*085 0*431
0-453
0*179
55
33
0*186
„
?5
33
0*181
„
2*06* „
33
0*183
Mean
0*183
in a platinum boat, then burned in a porcelain tube in
oxygen.
I.
II
III.
Carbon
99-11
98-52
Hydrogen . .
0-17
0-06
Ash
. . 0-26
0-27
0-51
99-55
99-09
The residual porous ash left after the combustion was tolerably white, with admixed red particles.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES. Ill
II. — Experiments with Naphtha A. Glass 1. Temperature of the Air 19°-0-18°*7.
T.
T'.
t\
t.
M.
m.
/•
y-
X.
sp. H.
0
o
grms.
grms.
gnu.
grm.
53-9
21-1
20-77
18-22
26-97
3-515
1-935
0-431
0-651
0-174
52-2
21-0
20-73
18-31
26-96
55
55
»
„
0-176
52*1
21*2
20-86
18-52
26-94
„
0-158
53-0
21-0
20-73
18-32
26-97
„
55
„
„
0-155
52-8
21-0
20-73
18-33
26-965
55
1-91*
„
„
0-160
Mean
0-165
III. — Experiments with Naphtha
A. Glass 3. Temperature of
1 the Air
■ 19°-9-20°-0.
T.
T'.
t'.
t.
M.
m.
/-
y-
X .
sp. H.
0
o
o
o
grms.
grms.
grms.
grm.
51-6
21*9
21-55
19-33
26-97
3-90
2-05
0-431
0-453
0-174
51-3
22-0
21-71
19-52
26-955
55
55
0-174
51-5
22-0
21-70
19-52
26‘97
55
55
0-168
51-5
21-9
21-63
19-42
26-96
5J
2-04*
55
55
0-175
Mean . . . 0T73
The average of the means of these three series of determinations, 0T83, 0T65, and
0T73, gives 0T74 as the specific heat of Ceylon graphite between 21° and 52°.
Iron graphite from Oberhammer, near Sayn, separated upon black ordnance iron.
Thin, very lustrous laminae, freed from iron by treatment with aqua regia as much as
possible, yet not completely f.
* After drying the stopper.
t This iron graphite, according to Mr. Huber’s analyses, in which it was also burned in oxygen in a plati=
i num boat placed in a porcelain tube, gave the following results : — •
I.
II.
III.
Carbon
. . 97-01
96-12
96-37
Hydrogen . .
0-12
0-18
Ash
. . 4-88
C»
3-99
101-89
101-11
100-54
It is probable that both in this graphite and in that of natural occurrence, the hydrogen is not essential, but
arises from hygroscopic moisture. The residual ash contained porous particles consisting of sesquioxide of iron
and silica, and also small pellets, covered externally with a layer of magnetic oxide of iron : these dissolved in
hydrochloric acid at first quietly, and afterwards under disengagement of hydrogen ; and in the solution small
blisters of graphite could he perceived. It is owing to the oxidation of the iron that the sum of the constituents
in all cases exceeds 100.
R
MDCCCLXV.
112
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
I. Experiments with Naphtha A. Glass 3. Temperature of the Air 19o-0-18°-7.
T.
T'.
t'.
t.
M.
m.
/•
y ■ ■
X,
sp.H.
O
grins.
grms.
grms.
grm.
52-5
20-8
20-53
18-21
26-955
2-51
2-445
0-431
0-453
0-186
52-9
21-1
20-84
18-54
26-98
55
2-565*
55
55
0-156
51-4
20-9
2064
18-43
26-94
„
55
,,
„
0-157
52-0
20-9
20-60
18-33
26-99
55
2-545f
„
55
0-168
Mean
0-167
.—Experiments with
Naphtha
A. Glass 1.
Temperature of the Air
19°-9-20°-0.
T.
T'.
t'.
t.
M.
ra.
/•
y-
oc.
sp. H.
o
O
0
o
grms.
grms.
grms.
grm.
52-1
21-9
21-57
19-32
26-94
2-48
2-205
0-431
0-651
0-164
51-7
22-0
21-66
19-45
26-97
55
55
55
55
0-163
51-5
22-0
21-73
19-54
26-98
55
55
„
0-162
51-5
22-0
21-66
19‘46
26-945
55
2-19f
55
55
0*167
Mean .
0T64
The average of the means of both these series of experiments, 0T67 and 0T64, gives
0T66 as the specific heat of iron graphite between 22° and 52°.
The results previously known in reference to the specific heat of carbon, differ greatly
for its different conditions, as also do the results obtained by different inquirers and
by different methods for the same condition. But even leaving out of consideration the
numbers obtained by De la Rive and Marcet by the method of cooling, there are still
considerable differences between Regnault’s results, obtained by the method of mixture,
and my own. Regnault found for animal charcoal 0-261, for wood-charcoal 0-241, for
gas-carbon 0-209, for natural graphite 0-202, for iron graphite 0*197, for diamond 0-1469 ;
his experiments gave greater numbers for the same substance than my own. I think that
exactly for a substance like carbon in its less dense modifications, my method promises
more accurate results than that of Regnault. Even in mine, the substance, after being
strongly heated before the experiment, might absorb gases or aqueous vapour, which
would make the specific heat too great. But in Regnault’s method this source of error
might also operate, and more especially also the source of error due to the disengage-
ment of heat when porous substances are moistened by water. These sources of error,
which affect the determination of the specific heat of the various modifications of carbon
and make it too high, have the more influence the looser and the more porous the sub-
stance investigated. I believe that the only certain determination of the specific heat
of carbon is that of diamond, and all other determinations are too high, owing to various
circumstances, and in Regnault’s experiments with wood and animal charcoal, &c.,
owing to the heat disengaged when these substances are moistened by water.
* After some more naphtha had been added.
t After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
113
37. Silicium. — I have investigated this substance in four different modifications.
Amorphous Silicium *. — For the experiments picked coherent pieces were used, which
had stood for several days in vacuo over sulphuric acid.
Experiments with Naphtha A. Glass 3. Temperature of the Air 19°-2.
T.
T'.
t'.
t.
M.
m.
/•
V'
X.
sp. H.
0
grms.
grm.
grms.
grm.
0-251
5l-5
20-7
20-38
18-13
26-95
1-095
2-88
0-431
0-453
50-0
20-8
20-54
18-46
26-975
55
„
99
99
0-208
50-4
21-0
20-66
18-55
26-98
„
,,
99
99
0-221
50-5
20-9
20-59
18-52
26-935
„
2-87f
„
99
0-177
Mean . . . 0-214
The very discordant results of these experiments are very little trustworthy ; the
quantity of silicium, 1 grm., was too small, and its thermal action inconsiderable as com-
pared with that of the other substances immersed with it in the water of the calorimeter.
Graphitoidal Silicium J.
Experiments with Naphtha A. Glass 3. Temperature of the Air 16°-7-17°-2.
T.
T'.
a.
t.
M.
m.
/•
y-
x. sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
51-0
18-8
18-51
16-34
26-965
3-155
1-83
0-431
0-453 0-182
52-3
19-1
18-82
16-59
26-975
99
99
99
„ 0-181
51-1
18-9
18-62
16-44
26-98
99
99
99
„ 0-185
50-4
18-8
18-52
16-43
26-95
l-81f
99
„ 0-174
Mean . . . 0-181
Crystallized Silicium . — Grey needles §.
Experiments with Naphtha A. Glass 1. Temperature of the Air 19°-1.
T.
O
T'.
o
t'.
0
t.
o
M.
grms.
m.
grms.
/•
grm.
y-
X.
grm.
sp. H.
53-8
21-1
20-83
18-53
26-94
2-395
1-955
0-431
0-651
0-168
52-6
21-0
20-74
18-52
26-975
99
99
99
,5
0-168
52-3
21-0
20-72
18-52
26-98
99
99
99
55
0-168
51-9
21-0
20-66
18-53
26-975
99
l-935f
Mean
55
0-156
0-165
* “ Prepared from silicofluoride of potassium by means of sodium.” — Wohler.
t After drying the stopper.
+ “ Obtained by melting silicofluoride of potassium, or sodium, with aluminium ; the aluminium was then
extracted with hot hydrochloric acid, and the oxide of silicium with fluoric acid.” — Wohler.
§ “ This silicium was prepared from the silicofluoride of potassium, or sodium, by sodium and zinc, and the
lead (from the zinc) removed by nitric acid. Whether it was afterwards treated with hydrofluoric acid 1
cannot say, but probably so. It was quite unchanged when heated in the vapour of hydrochlorate of chloride
of silicium (passed by means of hydrogen). Probably it contained, however, like all silicium reduced by zinc,
a trace of iron, which appears when it is heated in chlorine. An experiment with another portion of such
silicium gave, however, so little iron that its quantity could not be determined.” — Wohler.
R
114
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Fused Silicium *.
Experiments with Naphtha A. Glass 1. Temperature of the Air 18°*9-180,7.
T.
T'.
t'.
t.
M.
m.
/• y-
a?.
sp. H.
Q
grms.
grms.
grm.
grm.
0-142
49-0
20-5
20-24
18-40
26-97
417
1-555 0-431
0-651
50-5
20*7
20-43
18-52
26-96
99
55
0139
49-7
20-6
20-27
18-42
26-965
99
55 55
55
0136
50-8
20-7
20-43
18-52
26.94
99
l-145f „
55
0136
Mean . . . 0138
38. Tin : reduced from the oxide, cast in small bars.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 17°-8-180,8.
T.
T'.
t'.
t.
M.
m.
/•
y-
CO.
sp. H.
0
0
grms.
grms.
grm.
grm.
51-4
19-8
19-46
1714
26-965
14-835
1-385
0-431
0-651
0-0493
51-4
19-9
19-62
17-23
26-98
99
99
99
99
0-0539
51-3
20-0
19-72
17-34
26-95
99
99
99
0-0540
51-5
20-3
20-03
17-65
26-995
99
1-365 f „
99
0-0553
Mean
0-0531
11. — Experiments with Water. Glass
1. Temperature of the Air 15'
3-5-15°-9.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
0
o
o
grms.
grms.
grm.
grm.
45-1
17-5
17-24
14-13
26-975
14-62
1-595
1-000
0-651
0-0543
46-4
17-5
17-24
13-94
26-985
99
99
99
99
0-0571
45-6
17-6
17-34
1414
26-99
99
99
99
99
0-0574
45-7
17-6
17-34
1414
26-95
99
1-58 f
99
99
0-0573
Mean
0-0565
The average of the means of these two series of observations gives 0-0548 as the
specific heat of tin between 19° and 48° at 0-0548.
Platinum : several pieces of fused platinum and of thick platinum wire.
Experiments with Naphtha A. Glass 1. Temperature of the Air 170,8-18°-2.
T.
T’.
t'.
t.
M.
m.
/•
y •
X .
sp. H.
53-5
20-4
20-14
17-23
grms.
26-96
grms.
23-625
grm.
2-225
0-431
grm.
0-651
0-0322
52-8
20-0
19-65
16-73
26-975
99
99
99
99
0-0335
51-5
20-0
19-73
16-95
26-96
99
99
99
0-0326
50-9
20-0
19-74
17-05
26-96
„
2-205 f
99
99
0-0316
I have also made a few experiments with a piece of fused iridium which M. Herjsus
gave me.
"Wohler had obtained it from Detille ; it formed a cylindrical piece.
After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES. 115
Experiments with Naphtha A. Glass 3. Temperature of the Air 170,8-18°-2.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
O
o
o
o
grms.
grms.
grms.
grm.
51-8
19-5
19.24
16-93
26-995
16-66
2-04
0-431
0-453
0-0359
51-0
19-6
19-26
16-95
26-97
55
95
59
55
0-03911
50-0
19-5
19-24
17-06
26-965
59
55
55
59
0-0357
50-5
19-6
19-34
17-13
26-93
„
2-03 *
0-0359
Excluding
• the second experiment, which
is obviously uncertain, these determinations
give 0-0358 as the specific heat of iridium. This iridium was not free from metals of
smaller atomic weight and greater specific heat. For various specimens of impure
iridium, Regnault (Ann. de Chim. et de Phys. [2] vol. lxxiii. p. 53; [3] vol. xlvi.
p. 263 ; vol. lxiii. p. 16) found 0-0368, 0-0363, 0-0419, and for almost pure iridium
0-0326.
39. Silver : pure, cast in bars.
Experiments with Naphtha A. Glass 3. Temperature of the Air 18°-9-19°T.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
O
o
o
grms.
grms.
grm.
grm.
52-1
21-1
20-82
18-15
26-975
21-51
1-585 0-431
0-453
0-0552
51-5
21-1
20-77
18-14
26-99
55
55 55
55
0-0557
51-4
20-9
20-62
17-94
26-98
55
55 95
„
0-0574
50-9
21-0
20-65
18-06
26-95
55
59 55
„
0-0557
51-0
21-1
20-83
18-25
26-965
59
1-565* „
55
0-0558
Copper. — Commercial copper wires f .
I. — Experiment with Naphtha A. Glass 1.
Mean
Temperature
. . . 0-0560
of the Air 13°-2.
T.
T'.
t\
t.
M.
m.
/• y ■
X .
sp. H.
o
0
0
0
grms.
grms.
grm.
grm.
44-3
15-9
15-64
12-64
26-985
16-505
1-675 0-43]
. 0-651
0-0895
46-2
15-1
14-82
11-43
26-97
„
55 55
„
0-0949
45-7
15-2
14-91
11-63
26-97
55
55 55
55
0-0926
47-7
15-2
14-93
11-43
26-98
„
1-67* „
„
0-0930
* After drying the stopper,
t With reference to what has been said
in § 24, I
Mean
here communicate a series
. . . 0-0925
of experiments (one o
earliest) where t' was much more above the temperature of the air than usual, and hence too small numbers
were obtained for the specific heat of the substance in question.
Experiments with Naphtha A. Glass 2. Temperature 130-8.
T.
T'.
t'.
t.
M.
m.
/.
y>
X.
sp. H.
45-6.
16-5
16-23
13-02
grms.
26-98
grms.
18-33
grm.
1-96
0*431
grm.
0*487
0-0897
48-5
16-9
16-64
13-21
26-97
99
0-0870
43-7
16-5
16-15
13-21
26-98
99
1-95*
0-0867
* After drying the stopper.
116
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
II. — Experiments with Naphtha B. Glass 3. Temperature of the Air 19°‘4-19o,0.
T.
T'.
t'.
t.
M.
TO.
/• y-
X.
sp. H.
grms.
grms.
grm.
grm.
55-0
21-9
21-62
18-06
26-96
19-725
1-56 0-419
0-453
0-0909
54-1
21-4
21T1
17-60
26-965
55
55 55
55
0-0906
53-6
21-2
20-86
17-36
26-99
55
55 55
55
0-0917
54-2
21-3
20-96
17-44
26-98
55 55
55
0-0902
51-7
21-2
20-85
17-55
26-965
”
1-545 * „
Mean
55
0-0921
0-0911
hi.—:
Experiments with Water. Glass 1. Temperature of the Air 18!
o*
OO
i — 1
1
T.
T'.
t'.
t.
M.
TO.
/• y-
OB.
sp. H.
0
O
0
o
grms.
grms.
grm.
grm.
49-7
20-8
20-50
16-17
26-95
18-26
1-625 1-000
0-651
0-0965
50-0
20-6
20-32
15-93
26-96
55
55
0-0958
49-5
20-8
20-50
16-22
26-93
55
„
0-0953
47-9
20-9
20-62
16-64
26-945
55
1-615 * „
Mean
55
0-0934
0-0953
According to these determinations, the mean of the average results 0-0925, 0-0911,
0-0953, the number 0-093 represents the specific heat of copper between 20° and 50°.
40. Lead : reduced from sulphate of lead and cast in small bars.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 18°-9-18°-8.
T.
T'.
t'.
t.
M.
TO.
/•
y-
X.
sp. H.
O
O
o
o
grms.
grms.
grm.
grm.
50-5
20-6
20-33
18-23
26-995
19-93
1-465
0-431
0-651
0-0308
50-5
20-7
20-43
18-35
26-975
55
55
55
„
0-0302
50-9
20-7
20-44
18-35
26-965
55
55
55
55
0-0293
50-5
20-6
20-32
18-24
26-94
55
1-445
*
55
0-0302
Mean , . . 0-0301
II. — Experiments with Water. Glass 1. Temperature of the Air 15°-5-150,9,
T.
T'.
t'.
t.
M.
TO.
/•
y-
X .
sp. H.
46-0
o
17-5
17-21
14-02
grms.
26-96
grms.
24-845
grm.
1-56
1-000
grm.
0-651
0-0325
45-3
17-6
17-32
14-23
26-985
55
55
55
0-0322
45-9
17-7
17-42
14-25
26-945
55
55
55
55
0-0329
46-1
17-9
17-61
14-43
26-985
„
1-55 *
55
55
0-0339
Mean . . . 0-0329
The mean of the averages of both series of experiments, 0-0301 and 0-0329, gives for
the specific heat of lead between 19° and 48° the number 0-0315
* After drying the stopper,
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
117
Zinc : purified, cast in small bars.
I. — Experiments with Naphtha A. Glass 3. Temperature of the Air 170,8-18°-9.
,T.
T'.,
t'.
o
t.
o
M.
grms.
m.
grms.
/•
grm.
y •
X.
grm.
sp. H.
51-5
20-5
20-22
17*23
26-995
15-555
1-745
0-431
0-453
0-0899
51-1
20-3
19-95
16-96
26-985
„
55
55
55
0-0909
51-7
20-6
20-25
17-24
26-99
55
55
55
55
0-0905
50-9
20-5
20-23
17-25
26-945
55
1-72*
55
Mean
”
0-0930
0-0911
II. — Experiments with Water. Glass 1. Temperature of the Air 16o,0-16°-5.
T.
T'.
t'.
t.
M.
m.
/• y •
X .
sp. H.
o
o
o
o
grms.
grms.
grm.
grm.
43-0
17-7
17-43
13-82
26-98
14-25
1-855 1-000
0-651
0-0943
43-1
18T
17-84
14-26
26-965
55
55 55
„
0-0951
42-7
18-1
17-82
14-32
26-96
55
55 55
55
0-0933
42-7
18-4
18-05
14-54
26-99
55
55 55
„
0-0977
42-9
18-5
18-23
14-74
26-97
1-845 * „
55
0-0956
Mean . . . 0-0952
These determinations give 0-0932 as the mean of the means of the two series of
determinations for the specific heat of zinc between 19° and 47°.
Cadmium : cast in small bars.
Experiments with Naphtha A. Glass 1. Temperature of the Air 18°-9-19°T.
T.
T'.
t[.
t.
M.
m.
/•
2/*
X .
sp. H.
o
O
o
0
grms.
grms.
grm.
grm.
53-7
21-0
20-72
18-24
26-955
13-335
1-555
0-431
0-651
0-0542
51-6
20-9
20-56
18-23
26-97
55
55
55
55
0-0544
51-9
20-8
20-47
18-12
26-98
55
„
55
0-0538
52-3
20-8
20-52
18-14
26-975
„
1-535*
55
55
0-0544
Mean . . . 0-0542
Magnesium : metallic globules and masses comminutedf .
Experiments with Naphtha A. Glass 1. Temperature of the Air 180,6-19°1.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
O
o
o
grms.
grms.
grm.
grm.
53-3
20-6
20-32
17-74
26-995
3-485
1-42
0-431
0-651
0-249
51-8
20-6
20-26
17-83
26-97
55
0-240
51-0
20-6
20-33
17-94
26-99
,,
5}
0-247
51-6
21-0
20-72
18-33
26-96
„
1-40
*
55
„
0-244
Mean . . . 0-245
* After drying the stopper.
t “ The magnesium was prepared hy the methods of Deville and Caron, and Wohler. The reguline masses
were not remelted, hut treated with dilute hydrochloric acid, then washed with water and dried at a gentle
temperature.” — Engelbach.
118
PKOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Iron : pieces of iron wire.
I. — Experiments with Naphtha A. Glass 2. Temperature of the Air 130-2.
T.
T'.
t'.
t.
M.
m.
/•
y-
SC.
sp. H.
0
o
o
o
grms.
grms.
grm.
grm.
46-6
16-2
15-92
12-52
26-97
17-565
1-46
0-431
0-487
0-108
45-4
15T
14-83
11-33
26-95
55
„
,,
55
0-114
46-0
15-1
14-77
11-22
26-935
55
„
55
55
0-113
46-2
15-2
14-91
11-34
26-98
55
1-455
*
55
„
0-113
Mean
0-112
II. — Experiments with Water.
Glass
1. Temperature of the
Air 16°-
o"
r-
i— i
1
oo
T.
T'.
t'.
t.
M.
m.
/•
y •
sc.
sp. H.
O
0
a
o
grms.
grms.
grm.
grm.
43-2
18-8
18-46
15-02
26-985
15-57
1-425
1-000
0-651
0-111
42-9
19*1
18-84
15-47
26-975
55
55
,,
„
0-112
43-6
19*3
19-04
15-62
26-99
55
55
„
0-111
42-5
19*3
19-01
15-72
26-985
55
1-42*
55
55
0-113
Mean .
. .
0-112
The means of both series of experiments give for the specific heat of iron between
17° and 44° the number 0T12.
With reference to what has been said in § 24, the following series of experiments
made at the beginning of my investigation are given, in which t' exceeded the ordinary
temperature much more than usual, and hence the numbers for the specific heat of iron
were found somewhat too small.
Experiments with Naphtha A. Glass 1. Temperature of the Air 13°-8.
T.
T'.
t'.
t.
M.
m.
/•
y-
sc.
sp. H.
o
O
0
o
grms.
grms.
grm.
grm.
48-1
16-4
16-12
12-73
26-93
15-57
1-185
0-431
0-651
0-111
44-5
16-3
15-97
13-03
26-905
,,
„
„
„
0-106
45-7
16-6
16-26
13-23
26-97
55
55
„
55
0-106
47-0
16-7
16-43
13-23
26-96
55
1-17*
55
55
0-103
Another
source
of error
which
may make the numbers
for the specific heat <
substance investigated too small, has been discussed in § 18 and 24, — the circumstance,
namely, that the substance may fill the glass so densely as to impede the circulation of
the liquid, or make it impossible. This circumstance made the numbers for the
specific heat of chromium , which were obtained from the following series of observa-
tions, too small. The chromium was reduced from chloride of chromium according to
Wohler’s method by means of zinc (Ann. der Chem. und Pharm. vol.'cxi. p. 230);
the heavy, finely crystalline powder deposits in the glass as a dense mass impeding the
circulation. The following results were obtained : —
* After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
119
Experiments with Naphtha A. Glass 3. Temperature of the Air 19°*8-19°T.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
0
o
0
o
grm.
grms.
grms.
grm.
51-2
21-6
21*34
18*96
26*965
6*725
2*405
0*431
0*453
0*101
51*2
21-6
21*33
18*95
26*97
55
„
„
0*101
50-8
21-5
21*24
18*92
26*945
55
55
„
„
0*096
51*8
21-5
21*22
18*81
26*99
55
2*36 *
„
„
0*101
As the atomic weight of chromium is somewhat smaller than that of iron, it is to be
supposed that the specific heat of chromium is somewhat greater than that of iron.
Aluminium : a piece of a small bar f.
Experiments with Naphtha A. Glass 3. Temperature of the Air 18°*6-18°*4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
0
O
0
o
grms.
grms.
grm.
grm.
52*3
20*9
20*64
18*03
26*98
5*916
1*45
0*431
0*453
0*197
51*9
20*7
20*44
17*83
26*995
55
55
55
„
0*200
52*2
20*9
20*62
17*95
26*97
55
55
55
55
0*207
51*0
20*8
20*47
17*93
26*975
55
1*435
*
55
55
0*202
Mean . . . 0-202
42. Remisulphide of Copper, €u2S$. Copper-glance was investigated ; a dense spe-
cimen with conchoidal fracture from Liberty Mine in Maryland and a crystallized
specimen of unknown locality, which also I tested as to its purity.
Experiments with Naphtha A. Glass 1. Temperature of the Air 160,T.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
52*6
19*0
18*72
15*74
grms.
26*995
grms.
8*775
grm.
1*595
0*431
grm.
0-651
0*120
52*0
18*9
18*58
15*65
26*995
55
55
„
55
0*120
52*6
19*0
18*72
15*74
26*99
55
55
55
55
0*120
51*6
18*8
18*53
15*63
26*96
„
1*58 *
55
55 •
0*120
Mean . . . 0*120
* After drying the stopper.
t “ By remelting Paris aluminium, by which, it became poorer in iron ; contains probably still some iron
and silicium.” — Wohler.
+ All formulae of compounds whose specific heat is discussed in the following are written under the assump-
tion of the new atomic weights (see § 2).
MDCCCLXV.
S
120
PEOFESSOB KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Sulphide of Mercury, -HgS. Pieces of a sublimed cake of cinnabar*.
Experiments with Naphtha A. Glass 1. Temperature of the Air 20o,3-21°T.
T.
T'.
t\
t-
M.
m. f. y.
X.
sp. H.
O
o
o
o
grms.
grms. grm.
grm.
50-9
22-2
21-94
19-79
26-95
13-44 1-565 0-431
0-651
0-0516
51-8
22-3
22-02
19-80
26-95
55 55 55
35
0-0523
51-2
22-4
22-05
19-92
26-98
55 55 55
33
0-0499
51-8
22-4
22-14
19-93
26-98
„ 1-55 f „
Mean ,
”
0-0528
0-0517"
Sulphide of Zinc. -Zn -S. Fragments of crystals of black Zinc-blende from Bohemia.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°T.
T.
T'.
t'.
t.
M.
to.
/•
y-
sp. H.
■ 0
O
o
o
grms.
grms.
grm.
grm.
50-8
16-3
16-02
13-18
26-975
7-00
1-64 0
•431
0-651
0-123
46-7
16-1
15-83
13-33
26-935
55
55 •
55
55
0-120
44-1
15-9
15-63
13-32
26-94
55
55
55
55
0-121
44-8
16-2
15-93
13-63
26-94
5?
55
55
55
0-116
43-1
15-9
15-63
13-42
26-97
5?
1-625 f
55
55
0-120
Mean . . . 0T20
Sulphide of Lead, Pb -S. Cleavage fragments of Galena from the Harz.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°-5-14°-9.
T.
T'.
t\
t.
M.
TO.
/• y-
X.
sp. H.
o
o
0
o
grms.
grms.
grm.
grm.
51-3
16-4
16-05
13-34
26-93
13-835
1-78 0-431
0-651
0-0486
48-6
16-4
16-05
13-54
26-975
55
55 55
55
0-0495
45-7
16-1
15-83
13-53
26-95
55
55 55
55
0-0489
48-4
16-2
15-94
13-44
26-925
55
1-765 f „
Mean
55
0-0490
0-0490
* This cinnabar was found, on being tested, to be free from admixed uncombined sulphur. In experiments
with another specimen of beautiful crystalline appearance, I obtained considerably greater numbers for the
specific beat.
Experiments with Naphtha A. Glass 1. Temperature of the Air 160,3-16°-6.
T.
T'.
t'.
t.
M.
TO.
/-
y-
X.
sp. H.
0
O
o
o
grms.
grms.
grm.
grm.
53-0
18-5
18-23
15-72
26-975
9-805
1-72
0-431
0-651
0-0582
51-5
18-4
18-14
15-76
26-96
„
„
„
}>
0-0557
52-0
18-4
18-13
15-73
26-99
„
„
„
„
0-0546
51-6
18-5
18-16
15-81
26-97
1-70+
„
,,
0-0542
But the Naphtha which bad been in contact with this cinnabar, left on evaporation a considerable quantity of
sulphur, the admixture of which made the specific beat too large,
f After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
121
43. Sulphide of Copper and Iron, Cu Ee -S2, or Gu^Ee^S. Crystals and fragments of
crystalline masses of Copper pyrites from Dillenburg.
Experiments with Water.
Glass 1.
Temperature of the Air 17°-2-
-17° -5.
T.
T'.
t'.
t.
M.
m.
/•
y •
X.
sp. H.
47-5
o
19-1
18-82
15-22
grms.
26-975
grms.
7-365
grm.
1-825
1-000
grm.
0-651
0-128
48-0
19-4
19-12
15-44
. 26-985
55
99
99
„
0-135
47-6
19-5
19-23
15-65
26-975
59
„
99
55
0-131
48-1
19-6
19-25
15-64
26-985
59
59
95
55
0-128
47-6
19-5
19-23
15-64
26-94
59
1-81*
55
55
0-133
Mean . . . 0-131
Bisulphide of Iron, Ee S2. Small crystals and crystalline fragments of Iron pyrites
from Dillenburg.
I. — Experiments with Naphtha A. Glass 2. Temperature of the Air 130,3.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
O
o
o
0
grms.
grms.
grm.
grm.
47-1
16-0
15-66
12-74
26-92
10-11
1-81 0-431
0-487
0-125
46-2
15-9
15-61
12-77
26-93
„
55 55
59
0-124
47T
16-0
15-74
12-87
26-97
55
55 55
„
0-121
47-9
16-2
15-87
12-95
26-93
1-795 * „
55
0-121
Mean . . . 0-123
II. — Experiments with Water. Glass 3. Temperature of the Air 17°-4-17°'5.
T.
T'.
o
t'.
t.
M.
grms.
m.-
grms.
/•
grms.
y-
X.
grm.
sp. H.
47-1
19-7
19-43
15-33
26-97
10-145
2-295
1-000
0-453
0-127
47-5
19-7
19-42
15-23
26-955
„
„
„
55
0-130
47-6
19-8
19-47
15-33
26-965
59
55
,,
55
0-125
47-4
19-8
19-52
15-36
26-945
55
2-28* „
Mean
55
0-131
0-128
The average of the means of both these series of experiments, 0*123 and 0-128,
makes the specific heat of iron pyrites between 18° and 47°=0T26.
44. Suboxide of Copper, €u20. A crystalline fine-grained Bed copper-glance of con-
choidal fracture was used for investigation.
s 2
* After drying the stopper.
122
PKOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Experiments with Naphtha A. Glass 3. Temperature of the Air 160,7.
T.
T'.
t'.
t.
M.
m.
/• y-
X»
sp. H.
O
o
0
o
grms.
grms.
grm.
grm.
51-6
18-7
18-36
15-80
26-97
8-67
1-635 0-431
0-453
0-109
51-0
18-6
18-26
15-73
26-995
55
55 55
0-110
50-8
18-6
18-26
15-72
26-96
55 55
5?
0-112
52-3
18-6
18-33
15-66
26-95
”
1-625 * „
Mean
??
0-113
0-111
Oxide of Copper, €u O. Granular freshly ignited oxide of copper.
Experiments with Naphtha A. Glass 1. Temperature of the Air 17°T-170,9.
T.
O
51- 1
52- 0
51T
50-8
T'.
19-2
19-3
19*4
19-4
t'.
18-86
18- 95
19- 11
19-07
t.
16-23
16-23
16-43
16-43
M.
grins.
26-965
26-985
26-94
26-97
m.
grins.
6-295
/•
grm.
1-85
y-
0-431
1-83 * „
Mean
X.
grm.
0-651
sp. H.
0-123
0-126
0-132
0-131
0-128
Oxide of Lead , PbO. Larger pieces of litharge freed by the sieve from the finer
particles.
Experiments with Naphtha A. Glass 3. Temperature of the Air 17°-4-17°-6.
T.
O
T'.
O
t'.
0
t.
0
M.
grms.
m.
grms.
/•
grms.
y-
X.
grm.
sp. H.
51-5
19-1
18-83
16-51
26-965
10-17
2-11
0-431
0-453
0-0559
50-4
19-1
18-84
16-63
26-95
??
55
0-0532
49-2
19-0
18-73
16-56
26-98
„
55
55
0-0567
48-5
19-0
18-73
16-63
26-985
2'10 * „
Mean
55
0-0554
0-0553
Oxide of Mercury , HgO. Crystalline pieces of Mercurius prcecipitatus per se, freed
by the sieve from finer particles.
Experiments with Naphtha A. Glass 1. Temperature of the Air 170,4-170-6.
T.
T'.
t\
t.
M.
m.
/• y-
X.
sp. H.
O
0
0
0
grms.
grms.
grm.
grm.
53-1
19-3
19-03
16-64
26-985
8-45
1-925 0-431
0-651
0-0506
52-0
19-1
18-83
16-46
26-975
55
„
55
0-0547
51-5
19-1
18-83
16-53
26-935
55
„
0-0510
50-4
19-1
18-82
16-56
26-965
”
1-915 * „
Mean
55
0-0557
0-0530
Hydrate of Magnesia , MgO + H20. Transparent cleavage laminae of Brucite from
Texas in Pennsylvania. Dried at 40°-50°.
After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
123
Experiments with Naphtha A. Glass 3. Temperature of the Air 170-2.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
0
O
o
o
grms.
grms.
grms.
grm.
51-9
19-4
19-13
16-02
26-985
3-59
2-29 0-431
0-453
0-318
52-2
19-5
19-23
16-12
26-99
55
5> ?)
55
0-314
48-2
19-3
19-04
16-32
26-95
55
y>
55
0-305
49*2
19*6
19-32
16-53
26-985
55
2-27* „
Mean
55
0-310
0-312
45. Spinelle, Mg Al204f . Transparent crystalline grains from Ceylon of octahedral form.
I. — Experiments with
Naphtha A. <
Glass 1.
Temperature
of the Air ll°-5.
T.
T'.
t'.
t.
M.
in.
/•
y •
X.
sp. H.
o
0
0
o
grms.
grms.
grm.
grm.
45-6
13-8
13-52
10-88
26-925
5-025
1-325
0-431
0-651
0-202
44-1
13-5
13-23
10-68
26-965
55
55
55
55 •
0-204
46-0
13-8
13-46
10-84
26-96
55
55
55
55
0-193
44-8
13-9
13-55
11-04
26-975
55
1-32*
55
55
0-193
Mean
0-198
II. — Experiments with Naphtha A.
Glass 2.
Temperature
of the Air ll°-5,
T.
T'.
t'.
t.
H.
m.
/•
y-
X.
sp. H.
O
0
o
o
grms.
grms.
grm.
grm.
45-7
14-1
13-83
11-47
26-935
5-025
1-265
0-431
0-487
0-195
46-1
13-8
13-54
11-14
26-95
„
55
55
55
0-193
46-2
13-2
12-85
10-33
26-975
55
55
55
„
0-205
48-0
13-8
13-45
10-93
26-95
„
1-26*
55
55
0-190
Mean . . . 0T96
I subsequently received another quantity of spinelle grains, also from Ceylon, and
have made the following series of experiments with this material.
III. — Experiments with Naphtha A. Glass 1. Temperature of the Air 15°-5.
T.
T'.
t'.
t.
M.
in.
/•
y-
X.
sp. H.
o
o
o
0
grms.
grms.
grm.
grm.
46-6
17-7
17-36
14-53
26-94
7-53
1-34
0-431
0-651
0-187
47-5
17-8
17-46
14-53
26-96
„
55
55
55
0-190
47-6
17-8
17-54
14-63
26-965
55
55
„
55
0-187
48-4
17-8
17-54
14-54
26-95
55
1-32*
55
55
0-189
Mean . . . 0188
* After drying the stopper.
t Abich’s analysis of red spinelle from Ceylon (Rammeesberg’s ‘ Handbuch der Mineralchemie,’ p. 161),
gave the following results compared with those calculated by the above formula : —
A1„03. Cr203. MgO. FeO. Si02. Total.
Analysis 69-01 1-10 26-21 0-71 2-02 99-05
Calculation 71-99 „ 28-01 „ „ 100-00
124
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
These determinations give as the average of the means of the three series of experi-
ments (0T98, 0T96, and 0T88) 0T94 for the specific heat of spinelle between 15°
and 46°.
Chrome Iron Ore , Mg] -FeA Or* Al, G4#. Fragments of granular pieces, partly dis-
tinctly crystalline, of chrome iron ore from Baltimore.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°‘2-13°’8.
T.
T'.
n.
t.
M.
m.
/•
y-
cc.
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
47-6
16-4
16-12
13-14
26-97
7-625
1-63
0-431
0-651
0T63
46-9
16-5
16-24
13-38
26-985
33
J}
33
0-155
46-8
16-4
16-13
13-24
26-925
33
„
55
33
0-158
46-4
1.6-4
16-13
13-28
26-955
„
1-61 f
5J
33
0-159
Mean . . . 0459
Magnetic Iron Ore , Fe3 04. Small crystals and crystalline fragments from Pfitsch
in Tyrol.
I. — Experiments with
Naphtha A. Glass 1.
Temperature of the Air ll°-0.
T.
T'.
t'.
t.
M.
m.
/•
y -
X.
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
45-1
13-9
13-64
10-54
26-96
9-07
1-43 0
1-431
0-651
0-156
47-4
13-8
13-53
10-23
26-97
33
33
33
33
0-152
49T
14-1
13-84
10-42
26-98
33
33
33
0-151
47-6
14-1
13-83
10-54
26-92
33
1-415 f
33
33
0-152
Mean .
0-153
II. — Experiments with
. Water.
Glass
3. Temperature of the Air 19°-5-190,4.
T.
T'.
t'. .
t.
M.
m.
/•
y-
X.
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
43-5 :
21-6
21-32 :
18-02 26-985
10-625
1-925
1-000
0-453 0-159
42-7
21-6
21-32 :
18-13 26-99
33
33
33
t33
0-160
43-0 :
21-6
21-33 :
18-12 26-97
33
1-91 f
33
3 3,
0-158
Mean
. 0-159
These determinations give as the mean of the averages of the two sets of experi-
ments, 0-156 for the specific heat of magnetic iron ore between 18° and 45°.
* The admissibility of this formula for the ore investigated follows from the following comparison of the
results calculated from it, with those which Abich had obtained (Rammelsbebg’s £ Handbuch der Mineral-
chemie,’ p. 172) by the analysis, a of compact, b of crystallized chrome iron ore from Baltimore.
Cr203.
Al,03.
Fe O.
MgO.
Total.
Analysis
f a 55-37
13*97
19-13
10-04
98-51
' 1 b 60-04
11-85
20-13
7-45
99-47
Calculation . .
... 58-32
13-11
18-37
10-20 ’
100-00
f After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
125
46. Sesquioxide of Iron , Ee2 03. Crystals and crystalline pieces of specular iron
from St. Gotthard.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 12°*4-120,3.
T.
T'.
t'.
t.
M.
M.
/•
y-
x.
sp. H.
Q
grms.
grms.
grm.
grm.
47-0
14-8
14-47
11-38
26-97
7-51
1-74
0-431
0-651
0-158
46-4
14-7
14-43
11-43
26-975
33
33
55
33
0-153
45-8
14-7
14-44
11-52
26-925
„
„
„
„
0-150
45-8
15-0
14-73
11-83
26-98
33
1-72*
„
33
0-153
Mean
0-154
II.-
-Experiments with Water. Glass 1.
Temperature of
the Air
19°-5.
T.
T.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
0
O
0
0
grms.
grms.
grm.
grm.
44-1
21-5
21-17
17-81
26-97
8-845
1-935
1-000
0-651
0-161
43-6
21-6
21-26
18-01
26-985
33
33
33
55
0-158
42-5
21-5
21-23
18-12
26-985
„
33
55
0-159
42-8
21-6
21-33
18-22
26-98
33
1-92*
33
„
0-157
Mean
0-159
The specific heat of specular iron between 18° and 45°, according to these determi-
nations, is 0T57, the mean of the averages of both series of experiments 0T54 and
0-159.
Iserine, Ee6 Ti3 03 f . Indistinct crystalline grains from the Iserwiese in the Riesenge-
birge.
Experiments with Naphtha A. Glass 2. Temperature of the Air 140,2-130'8.
T.
T'.
t'.
t.
M.
m.
/•
y-
x. sp. H.
o
o
0
o
grms.
grms.
grm.
grm.
46-6
17-1
16-77
13-43
26-975
11-145
1-415
0-431
0-487 0-176
47-0
16-7
16-43
12-97
26-98
33
„
33
,, 0-178
46-5
16-6
16-33
12-93
26-93
33
33
33
„ 0-176
47-0
16-9
16-56
13-15
26-98
33
1-39 *
33
Mean
„ 0-177
. . . 0T77
* After drying the stopper.
f This formula corresponds to the composition assumed by Rammelsberg (Handbuch der Mineralchemic,
pp. 413, 1015) for iserine from the Iserwiese, namely, 3 (FeO Ti 02)+Fe3 03.
126
PKOFESSOB KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Oxide of Chromium , Cr2 03. Crystalline crusts prepared from oxychloride of chromium.
Experiments with Naphtha A. Glass 3. Temperature of the Air 19°T.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
52-1
21-5
21*23
18*53
grms.
26*955
grms.
5*405
grm.
2*255
0*431
grm.
0*453
0*176
51-5
2T2
20*93
18*22
26*955
55
55
55
0*181
53-1
21-4
21*06
18*25
26*945
55
55
55
55
0*178
52-1
21*2
20*94
18*23
26*99
55
2*245 *
55
„
0*175
Mean . . . 0T77
Hydrated Sesguioxide of Manganese Mn2 03-|-H2 Of. Fragments of good crystals
of Manganite from Ihlefeld in the Harz, dried at 40° to 50°.
Experiments with Naphtha A. Glass 3. Temperature of the Air 14°*6-14°*4.
T.
T'.
t\
t.
M.
m.
/• y-
X .
sp. H.
c
0
o
grms.
grms.
grm.
grm.
47*0
17*1
16*82
13*83
26*985
8*31
1*855 0*431
0*453
0*174
45*6
17*0
16*69
13*83
26*94
55
55 55
55
0*173
45*7
17*0
16*73
13*85
26*92
”
1*845* „
Mean
55
0*174
0*174
I made subsequently another series of experiments with a specimen from the same
locality dried at the ordinary temperature.
Experiments with Naphtha A. Glass 3. Temperature of the Air 17°*7— 1 7°*4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
o
0
0
grms.
grms.
grm.
grm.
52*0
20*5
20*15
17*06
26*95
8*04
1*77
0*431
0-453
0*178
52*3
20*3
2Q-02
16*86
26*975
55
55
55
55
0*180
51-9
20*1
19*77
16*65
26*965
55
55
55
55
0*178
51*6
20*1
19*84
16*80
26*995
55
1*75
%
55
55
0*174
Mean
0*178
The specific heat of manganite between 19° and 49° is 0T76, the mean of the
averages of both series of determinations.
* After drying the stopper.
t “ Manganite dried at about 80°-90°, and then kept for half a day over sulphuric acid, gave in a ■water-
determination, in which the water was collected in a chloride of calcium tube, 9-96 per cent, of water.” — Knop.
The above formula requires 10-23 per cent, of water.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
127
47. Binoxide of Manganese, Mn 02. Pyrolusite from Ilmenau, dried at 100°-110°*.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°*4-140,5.
T.
T'.
ti.
t.
M.
m.
/•
y-
X .
sp. H.
5T6
o
17-0
16-70
13-41
grins.
26-955
grms.
6-32
grms.
2-06
0-431
grm.
0-651
0-162
48-5
16-9
16-63
13-63
26-945
55
55
55
55
0-161
45-9
16-9
16-61
13-86
26-93
55
55
55
55
0-161
44-0
16-9
16-64
14-13
26-97
55
2-04 f
55
99
0-153
Mean . . . 0T59
Titanic Acid, Ti G2. I have investigated the one quadratic modification, rutile, and
the rhombic modification Brookite or Arkansite ; I had no material for the investigation
of anatase, the other quadratic modification.
Rutile. Fragments of crystals from Saxony and from France.
Experiments with Naphtha A. Glass 1. Temperature of the Air 130,5-130,7.
T.
T'.
ti.
t.
M.
m.
/■
y-
X.
sp. H.
0
O
o
0
grms.
grms.
grm.
grm.
47-9
16-0
15-73
12-63
26-95
8-055
1-60
0-431
0-651
0-159
47-6
16-1
15-78
12-73
26-97
55
55
5?
0-158
45-2
15-9
15-56
12-73
26-965
55
55
„
,,
0T56
45-6
16-1
15-84
13-01
26-965
55
l-58f
„
5?
0-156
Mean . . . 0T57
Brookite or Arkansite. Beautiful small crystals from hotsprings in Arkansas, puri-
fied by treatment with hydrochloric acid from adherent oxide of iron.
Experiments with Naphtha A. Glass 1. Temperature of the Air 16°T-160,3.
T.
T'.
ti.
t.
M.
m.
/•
y-
X.
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
47-1
18-2
17-94
15-22
26-97
8-00
1-415
0-431
0-651
0-160
49-3
18-5
18-23
15-22
26-96
55
,,
5?
0-161
49-2
18-7
18-40
15-52
26-935
55
55
55
55
0T60
49-0
18-6
18-31
15-43
26-96
55
1-395 f
55
55
0-163
Mean . . . 0T61
.* This pyrolusite was not pure binoxide, but probably contained some manganite also. In experiments made
by Mr. Oeseb in the Giessen laboratory, this pyrolusite, dried at 100° to 110°, gave, when heated in a current
of dry air, the water being collected in a chloride of calcium apparatus, 1-21 per cent, of water ; treated with
oxalic acid, 'as much carbonic acid was disengaged as corresponded to 95-36 per cent, of binoxide. As the
specific beat of manganite (0-176) does not very much differ from that found for pyrolusite (0-159), I neglected
to introduce a correction for the small quantity of manganite.
t After drying the stopper.
MDCCCLXV.
T
128 PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Binoxide of Tin, Sn G2. Fragments of crystals of tinstone from Saxony.
Experiments with Naphtha A. Glass 2. Temperature of the Air 140,5.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
O
0
0
grins.
grms.
grm.
grm.
50-4
17-0
16-66
13-52
26-99
14-495
1-71
0-431
0-487
0-0906
46-6
16-4
16T4
13-33
26-925
55
55
55
55
0-0884
45-1
16-4
16-05
13-35
26-96
55
55
59
55
0-0905
45-7
16-3
16-04
13-32
26-98
55
1-695
*
55
„
0-0882
Mean . . . 0-0894
48. Silicic Acid, Si 02. Pieces of transparent quartz (rock-crystal) from the Grimsel.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 17°-7-17°'4.
T.
T'.
t'.
t.
M.
m.
/• y •
X.
sp. H.
grms.
grms.
grm.
grm.
53-8
20-1
19-83
17-03
26-99
4-88£
► 1-58 0-431
0-651
0T86
52-5
19-8
19-53
16-77
26-96
55
5 5 55
55
0-193
51-8
19-7
19-43
16-77
26-98
55
55 55
55
0-185
51-7
19-7
19-42
16-76
26-945
55
55 55
55
0-186
52-7
19-7
19-35
16-64
26-96
55
1-56 * „
55
0-182
Mean
0-186
II. — Experiments with Naphtha A. Glass 3.
Temperature of the Air 19°T-19°-4.
T.
T'.
t'.
t.
H.
m.
/• y-
X.
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
51-5
21-0
20-74
18-36
26-985
5-135
1-635 0-431
0-453
0-185
51-0
21-1
20-79
18-45
26-96
55
55 55
55
0-185
52-6
21-2
20-92
18-45
26-955
55
55 55
55
0-187
52-6
2i*2
20-89
18-42
26-97
55
1-62* „
55
0-189
Mean
0-187
III. — Experiments with Naphtha B. Glass 3.
Temperature of the Air 17°-8-17°-9.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
0
0
o
o
grms.
grms.
grm.
grm.
50-0
20-0
19-69
17-27
26-98
5-645
1-70 0-419
0-453
0T75
50-5
19-9
19-64
17-14
26-97
,,
55 55
55
0-184
50-0
20-1
19-82
17-40
26-99
„
55 55
5J
0T81
50-0
20-0
19-66
17-22
26-975
1-685* „
5J
0-178
Mean
0-180
* After drying the stopper.
PEOEESSOE KOPP ON THE SPECIFIC HEAT OE SOLID BODIES.
129
IV. — Experiments with Water. Glass 1. Temperature of the Air 170,8-18°-3.
T.
T'.
t'.
t.
M.
m.
/• >
X.
sp. H.
O
O
o
o
grms.
grms.
grm.
grm.
47-6
19-7
19-37
15-72
26-945
5-02
1-93 1-000
0-651
0-188
47-9
19-9
19-57
15-92
26-95
55
55 55
55
0-186
47-6
20-0
19-65
16-03
26-985
55
55 55
55
0-191
47-3
20-0
19-67
16-08
26-98
55
1-915* „
0-196
Mean . . . 0T90
The average of these four means, 0T86, 0T87, 0T80, 0T90, gives 0T86 as the
specific heat of quartz between 20° and 50°.
It was interesting to determine also the specific heat of amorphous silicic acid. I ac-
cordingly made experiments with opal and with hyalite, taking into account the water
contained in these minerals. If the quantity of silica in the mineral taken is m , that
of the water in it w, and z the specific heat of the water contained in the mineral, then,
taking the other symbols in the sense hitherto assigned to them, the specific heat of
the silica in the mineral can be calculated by the formula
sp. H=
M(t'—t) — (x+fy + wz) (T— T')
m (T-T')
But though the quantity of water contained in the (air-dried) minerals investigated
is so small (scarcely exceeding 4 per cent.), the specific heat of silicic acid is found to
be very different, according as (a) the specific heat z is put equal to 1, that of liquid
water, (/3) or equal to 048, that of solid water or ice (which is at least correct for
far the greater part of the water of these minerals, vide § 97). I give as follows,
under a and (3, the numbers resulting from both calculations.
Noble Opal from Honduras: yellowish, colourless in small pieces. The air-dried
mineral contained 4-3 per cent, of water ; in the following experiments 4T2 grms. of
opal were used, containing, therefore, 3- 943 grms. of anhydrous substances ( m ) and
0T77 grm. of water (w).
Experiments with Naphtha B. Glass 3. Temperature of the Air 18°-5-18°-7.
T. T'. t'. t. M. m. w. f. y. x. sp. H.
o o o o grms. grms. grm. grm. grm. a. (}.
50- 4 20-6 20-34 18-10 26-98 3-943 0-177 1-69 0-419 0-453 0-175 0-198
52-6 20-6 20-32 17-84 26-985 „ „ „ „ „ 0-191 0-214
51- 9 20-6 20-32 17-92 26-98 „ „ „ „ „ 0-185 0-209
51-3 20-6 20-32 17-96 26-955 „ „ 1-67* „ „ 0-188 0-211
Mean . . . 0-185 0-208
Hyalite from Steinheim near Hanau. Small limpid spheroidal masses. The air-
dried mineral contained 3-65 per cent, of water. In the following experiments 3‘795
* After drying the stopper.
T 2
130 PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
grms. of hyalite were used, which therefore contained 3*656 grms. of anhydrous sub-
stance (m) and 0*139 grm. of water (w).
Experiments with Naphtha B. Glass 1. Temperature of the Air 17°*8-17°*9.
T. T'. t'. t. ■< M. m. w. f. y. x. sp. H.
o o o o grms. grms. grm. grm. grm. a. (i.
50*4 19*8 19*50 17*26 26*98 3*656 0*139 1*345 0*419 0*651 0*170 0*190
0*172 0*192
0*175 0*194
0*173 0*193
0*173 0*192
In another series of experiments 4*475 grms. of hyalite were used, containing
4*312 grms. anhydrous substance (m) and 0*163 grm. water (w).
Experiments with Water. Glass 1.
Temperature of the Air 17°
*1-17°*2.
T.
r.
t'.
t.
M.
m.
w.
/• y-
X .
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
grm.
a. /3.
43*5
18*9
18*55
15*41
26*97
4*312
0*163
1*88 1*000
0-651
0*174 0*193
42*7
19*1
18*83
15*79
26*99
55
55
55 55
55
0*182 0*201
42*7
19*2
18*87
15*84
26*955
55
„
55 55
55
0*181 0*201
42*9
19*2
18*94
15*92
26*955
55
55
1*865* „
Mean .
55
0*175 0*195
0*178 0*197
The specific heat of amorphous silica must lie between the numbers standing
under a and (3, and coming nearer those under (3. It does not seem to differ materially
from that found for crystallized silica.
49. Molybdic Acid, Mo Os. Greyish-white powder, which, when heated in a porce-
lain crucible, became permanently bright grey : the results are not trustworthy.
Experiments with Naphtha A. Glass 3. Temperature of the Air 19°*5-20°*1.
T.
T'.
t'.
t.
M.
m.
/•
y •
X .
sp. H.
o
o
0
0
grms.
grms.
grms.
grm.
51*4
20*9
20*64
18*44
26*99
2*27
2*65
0*431
0*453
0*155
51*3
21*3
21*04
18*88
26*97
55
55
„
0*153
51*5
21*4
21*12
18*94
26*995
55
>5
55
55
0*159
51*2
21*4
21*06
18*93
26*96
55
2*635
*
55
55
0*149
Mean
. , *
0*154
50*8 19*8 19*51 17*23 26*98
50*4 19*8 19*53 17*27 26*97
51*4 19*8 19*53 17*21 26*98
1*33*
IVfpnn
After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
131
Tungstic Acid , W 03. Yellow powder.
Experiments with Naphtha A. Glass 1. Temperature of the Air 19o,5-20°T.
T. T'. t'. t. M. m. f. y. x. sp. H.
o o o o grms. grms. grm. grm.
52T 21-3 21-02 18-60 26-98 6*89 1-965 0-431 0-651 0-0902
52-8 21-5 21-16 18-73 26-99 „ „ „ „ 0-0868
50- 5 21-4 21-14 18-84 26-965 „ „ „ „ 0-0919
51- 9 21-6 21-29 18-93 26-985 „ 1-95* „ „ 0-0886
Mean . . . 0-0894
Of the above pulverulent metallic acids only small quantities were used, and their
thermal action was only a small proportion of the whole thermal action observed. The
results can only be considered as approximations to the true specific heat.
50. Chloride of Sodium, Na Cl. Pure chloride of sodium fused.
Experiments with Naphtha A. Glass 1. Temperature of the Air 10o"9-ll°-5.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
o
0
o
grms.
grms.
grm.
grm.
45-8
12-3
11-97
9-34
26-91
3-65
1-57
0-431
0-651
0-215
45-5
12-7
12-44
9-88
26-94
55
55
,,
0-212
45-7
13-0
12-74
10-20
26-99
55
1-56*
55
„
0-212
Mean . . . 0-213
Almost clear pieces of rock-salt, sharply dried.
Experiments with Naphtha A. Glass 2. Temperature of the Air 10°-9-ll°-5.
T.
T'.
t'.
t.
M.
m.
/• y-
X .
sp. H.
o
0
0
o
grms.
grms.
grms.
grm.
44-8
12-6
12-32
9-63
26-95
3-955
2-025 0-431
0-487
0-225
45-8
13-0
12-73
10-04
26-935
55
55 55
55
0-214
44-6
13-3
13-01
10-43
26-95
55
2-015 * „
Mean
”
0-219
0-219
Chloride of Potassium, K Cl. Pure salt fused f .
I. — Experiments with Naphtha A. Glass 2. Temperature of the Air 12°T-12°-2.
T. T'. t'. t. M. m. f. y. x. sp. H.
o o o o grms. grms. grm. , grm.
46-3 14-0 13-73 11-24 26-98 3-665 2-265 0-431 0-487 0-168
45-7 14-2 13-86 11-44 26-99 „ „ „ „ 0-167
* After drying the stopper.
t These experiments with fused chloride are more trustworthy than those with crystallized salt, which,
however, are very near ; for the latter, in loose crystals, only in small quantity, filled the glass used in the
determinations. The experiments with sharply dried crystallized chloride of potassium gave the following
results : —
132
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
II. — Experiments with Naphtha A. Glass 2. Temperature of the Air 10°*9.
T.
T'.
t'.
t.
M.
m.
/-
y-
X.
sp. H.
46*0
o
12*7
12*41
9*98
grms.
26*95
grms.
3*685
grm.
1*915
0*431
grm.
0*487
0*178
45*6
12*8
12*53
10*15
26*96
„
99
99
„
0T75
46*4
13*0
12*74
10*34
26*955
99
99
99
99
0*169
45*0
12*9
12*64
10*34
26*975
99
1*90*
99
99
0*170
The mean of the preceding six determinations gives 0T71 as the specific heat of
chloride of potassium between 13° and 46°.
Chloride of Rubidium, Rb Cl. Pure salt fused.
Experiments with Naphtha A. Glass 2. Temperature of the Air 14°*3-14°*5.
T.
T'.
o
t'.
t.
0
M.
grms.
m.
grms.
/•
grm.
y-
X.
grm.
sp. H.
47*9
16*1
15*84
13*64
26*96
5*22
1*835
0*431
0*487
0*112
46*0
16*2
15*92
13*83
26*975
99
99
„
99
0*118
44*3
16*2
15*93
14*00
26*94
99
99
99
99
0*110
43*8
16*4
16*13
14*26
26*98
”
1*82*
99
Mean
99
0*109
0*112
51. Chloride of Ammonium , NH4 Cl. I have made five series of experiments with
different forms of this salt.
Chloride of Ammonium , crystallized from pure aqueous solution in very small octa-
hedra.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 12°T-11°*8
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
0
0
0
• o
grms.
grm.
grms.
grm.
51*3
13*7
13*43
10*39
26*96
1*445
2*255 0*431
0*651
0*387
44*9
13*7
13*44
10*93
26*99
„
99 99
99
0*380
44*6
14*0
13*70
11*26
26*905
„
2*245* „
99
0*365
Mean . . . 0*377
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 12°-l-12°-2.
T.
T'
t\
t.
M.
m.
/•
y-
X.
sp. H.
o
O
0
0
grms.
grms.
grms.
grm.
44-1
13-7
13-39
11-11
26-945
1-795
2-485
0*431
0-651
0-166
47*0
14-1
13-84
11-42
26-96
»
»
99
0-145
II.-
-Experiments with Naphtha A.
Glass 1.
Temperature of the Air 12°-9.
45-6
14-5
14-22
11-90
26-945
2-365
2-125
0-431
0-651
0-187
45-7
14-4
14-14
11-90
26-98
,,
}J
0-154
46-5
14-7
14-43
12-14
26-955
2-115*
„
0-160
* After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
133
II. — Experiments with Naphtha A. Glass 2. Temperature of the Air 120,9.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
O
o
0
o
grms.
grm.
grms.
grm.
47-0
14-5
14-24
11-45
26-93
1-88
2-495 0-431
0-487
0-399
45-0
14-8
14-46
11-93
26-98
95
55 55
55
0-371
45-1
14-8
14-46
11-93
26-99
”
2-485* „
Mean
55
0-370
0-380
Only a small quantity of this finely crystallized chloride of ammonium goes into the
glasses which I used for the experiments. Hence I also investigated chloride of ammo-
nium in more compact pieces.
Long fibrous pieces from a sublimation cake :
III. — Experiments with Naphtha A. Glass 2. Temperature of the Air 12°T-11°'8.
T.
T'.
t'.
t.
M. , m.
/• y-
X.
sp. H.
0
0
o
o
grms. grms.
grms.
grm.
45-5
13-9
13*63
10-73
26-97 2-76
2-20 0-431
0-487
0-377
45-1
14-2
13-92
11-07
26-97 „
55 55
55
0-381
44-2
14-2
13-93
11-20
26-98 „
2-19* „
Mean
55
0-371
0-376
From the so-called “ gas liquor,” Noellner has prepared a very pure chloride of am-
monium, apparently in quadratic trapezoedra. With such crystals, 8 to 10 millims.
long, I made the following determinations : —
. — Experiments with Naphtha A. Glass 1.
Temperature of the Air
14°-1-
T.
T'.
t.
t.
M.
m.
/• y-
X.
sp. H.
o
o
o
o
grms.
grm.
grms.
grm.
48-5
15-9
15-63
12-84
26-99
1-978
2-085 0-431
0-651
0-384
44-7
16-0
15-73
13-32
26-93
„
55 55
55
0-360
44-8
16-0
15-70
13-32
26-97
59
2-075* „
Mean
”
0-346
0-363
Finally, I examined chloride of ammonium which had crystallized, from a solution
containing urea, in beautiful transparent cubes of 2 to 3 millims. in the side.
V. — Experiments with Naphtha A. Glass 2. Temperature of the Air 14°T-13°-8.
T.
o
T'.
t'.
o
t.
o
M.
grms.
m.
grms.
/•
grms.
y-
X.
grm.
sp. H.
45-2
16-0
15-73
13-05
26-92
2-595
2-34
0-431
0-487
0-376
44-4
16-1
15-83
13-25
26-975
55
55
95
55
0-371
45-7
16-4
16-08
13-45
26-96
55
2-33* „
Mean
55
0-358
0-368
The mean of the means of the five series of determinations, 0-377, 0-380, 0-376, 0-363,
0-368, gives 0-373 for the specific heat of chloride of ammonium between 15° and 45°.
* After drying the stopper.
134
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
52. Chloride of Mercury, Hg Cl2. Well-dried crystals.
Experiments with Naphtha A. Glass 1. Temperature of the Air 9°*2.
T.
T'.
t'.
t.
M.
m.
/•
y-
oc.
sp. H.
O
o
0
o
grms.
grms.
grms.
grm.
45*2
11*5
11*17
8*86
26*985
6*07
1*885
0*431
0*651
0*0636
44*3
11*2
10*90
8*50
26*99
55
2*105*
55
5J
0*0657
46*1
11*5
11*21
8*72
26*915
55
2*10f
55
0*0628
Mean . . . 0*0640
Chloride of Magnesium , Mg Cl2. Pieces of a beautiful preparation which had solidi-
fied with crystalline structure after being melted.
Experiments with Naphtha A. Glass 1. Temperature of the Air 13°*2.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
o
0
o
grms.
grms.
grms.
grm.
47*5
14*8
14*53
12*13
26*98
2*235
2*01 0*431
0-651
0*207
46*4
15*0
14*72
12*43
26*98
55
55 55
55
0*201
45*6
15*1
14*84
12*63
26*96
55
2*115* „
55
0*175
46*9
15*3
15*03
12*73
26*945
55
2*105f „
Mean
55
0*180
0T91
Chloride of Barium , Ba Cl2. Pieces of a specimen which was of a dead white colour
after solidifying.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°*4.
T.
T'.
t'.
t.
M.
m.
/.
y-
X.
sp. H.
o
o
0
0
grms.
grms.
grm.
grm.
46*2
16*2
15*87
13*64
26*975
6*795
1*72
0*431
0*651
0*0902
48*0
16*3
16*02
13*64
26*96
55
55
55
„
0*0930
47*1
16*3
16*03
13*73
26*945
55
55
55
„
0*0912
46*4
16*2
15*94
13*73
26*97
55
l*705f
55
55
0*0865
Mean . . . 0*0902
Crystallised Chloride of Barium, Ba Cl2+ 2H20. Crystals dried in vacuo.
Experiments with Naphtha A. Glass 3. Temperature of the Air 16°T-16°*8.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
o
o
0
o
grms.
grms.
grms.
grm.
45*5
17*6
17*34
15*04
26*975
5*055
2*14
0*431
0*453
0*168
47*1
17*8
17*50
15*03
26*955
55
55
55
55
0*177
47*0
18*0
17*74
15*33
26*975
5J
55
55
0*171
46*2
18*2
17*94
15*63
26*965
55
2*125f
55
55
0*169
Mean . . . 0*171
* After adding some more naphtha. (The naphtha was apparently sucked up by the crystals of chloride of
mercury, hence more naphtha was added. The liquid formed a smeary border at the side of the glass, but
there was no deliquescence of the crystals in the naphtha.)
f After drying the stopper.
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
135
Chloride of Chromium, €r2 Cl6. Violet insoluble chloride of chromium twice boiled
out with water, washed and dried at 130°. As a porous mass this substance is but ill
suited for an accurate determination of the specific heat. I pressed it, by means of a glass
rod, in a glass tube into small disks, between which the naphtha could circulate. Th e
object of this is to prevent a stagnation of the liquid absorbed by the solid mass, in
consequence of which the water of the calorimeter assumes its maximum more slowdy,
and hence the specific heat is found too low (compare §§ 18 & 24) ; but this object is not
quite attained in this way*.
Experiments with Naphtha A. Glass 1. Temperature of the Air ll0-4-ll°-5.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
O
O
o
o
grms.
grms.
grms.
grm.
47-5
13-2
12-86
10-32
26-93
3-165
2-095 0-431
0-651
0-139
47-5
13-0
12-73
10-13
26-97
55
55 55
„
0-151
43-8
12-9
12-63
10-33
26-945
55
55 55
55
0-143
46-0
13-0
12-65
10-21
26-94
55
2-085f „
55
0-140
Mean . . . 0T43
I should have liked to determine the specific heat of a solid metallic chloride of the
formula 11 Cl3, and tried with chloride of antimony, but it coloured naphtha yellow
when poured upon it, and became itself milky white, forming a heavy layer below the
naphtha, and fused completely a little above 40°.
53. Chloride of Zinc and Chloride of Potassium, ZnK2Cl4. Crystals dried at 100°
to 110°$.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°-3-14°-5.
T.
T'.
i.
t.
M.
in.
/•
y-
X.
sp. H.
o
o
o
0
grms.
grms.
grms.
grm.
48-7
16-2
15-93
13-53
26-915
3-01
2-02
0-431
0-651
0-155
47-1
16-3
16-04
13-77
26-965
55
,,
55
55
0-155
46-5
16-4
16-12
13-92
26-955
55
„
55
0-150
44-1
16-4
16-14
14-13
26-94
55
2-00f
55
„
0-147
Mean . . . 0T52
* The above source of error was of more importance, and the experiments gave far lower numbers for the
specific heat of chloride of chromium when this body was not formed in disks, but just placed in the vessel and
moderately lightly pressed. The following results were obtained in this manner : —
Experiments with Naphtha A. Glass 2. Temperature of the Air ll°-5.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
46-4
O .
13-4
13-12
10-52
grms.
26-915
grms.
2-425
grms,
3-035
0-431
grm.
0-487
0-134
45-6
13-8
13-53
11-04
26-985
„
„
0-131
45-7
13-8
13-52
11-02
26-99
yy
yy
0-132
45-6
13-8
13-48
11-02
26-95
„
3-015f
yy
0-123
f After drying the stopper.
+ “ These crystals were deposited from a solution which contained for one equivalent of chloride of potassium
MDCCCLXV. U
136
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Hydrated Chloride of Copper and Potassium , €uK2Cl4+2H2G. Air-dried crystals.
Experiments with Naphtha A. Glass 3. Temperature of the Air 17°-0-17°-2.
T.
T'.
t'.
t:
M.
m.
/•
y-
X.
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
51-4
19-1
18-80
16-33
26-95
4-085
1-86
0-431
0-453
0-197
50-4
19-0
18-66
16-26
26-94
55
55
55
55
0-197
50-0
19-1
18-77
16-43
26-955
„
55
55
0-193
49-2
19-0
18-68
16-35
26-95
59
1* *84*
55
55
0-204
Mean . . . 0-197
Chloride of Tin and Potassium, Sn K2 Cl6. Crystals dried at 105°-
Experiments with Naphtha A. Glass 3. Temperature of the Air 16°-4-17°-3.
T.
T'.
t'.
t.
M.
m. /.
y-
x. sp. H.
Q
Q
o -
o
grms.
grms. grm.
grm.
50-1
18-3
17-97
15-70
26-96
5-305 1-77
0-431
0-453 0-134
51-1
18-7
18-42
16-12
26-93
9 9 55
55
„ 0-131
49-5
18-7
18-36
1.6-19
26-955
55 55
55
„ 0T29
49-1
18-8
18-52
16-34
26-965
„ 1-76*
55
„ 0-137
Mean . . . 0-133
Chloride of Platinum and Potassium, Pt K2 Cl6. Well-formed small'crystals.
Experiments with Naphtha A. Glass 2. Temperature of the Air ll°-5-ll°-2.
T.
T\
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
O
o
o
grms.
grms.
grm.
grm.
44-3
13-2
12-91
10-55
26-93
7-25
1-55
0-431
0-487
0-122
46T
13-4
13-06
10-67
26-975
55
55
„
55
0-113
47-9
13-5
13-18
10-68
26-975
55
55
55
0-111
48-1
13-5
13-23
10-76
26-98
1-535
*
55
55
0-107
Mean . . . 0-113
at least two equivalents of chloride of zinc. In the analyses (the potassium was not determined) there were—
Found 24-0 per cent. Zinc, 49-3 and 49-6 Cl.
Calculated .... 22-85 per cent. Zn, 49*75 per cent. Cl, and 27*40 K.
“ The crystals were only pressed between paper, and hence were impregnated with some mother-liquor, which
explains the excess of zinc found.” — Engelbach.
* After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
137
54. Fluoride of Calcium , €a Fl2. Cleavage pieces of fluor-spar from Miinsterthal in
Baden.
Experiments with Naphtha A. Glass 1. Temperature of the Air 18°-4-19T.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
50-5
20-7
20-42
17-67
grms.
26-985
grms.
5-675
grin.
i 1-56
0-431
grm.
0-651
0-206
49-9
20-4
20-07
17-33
26-94
„
99
99
0-208
50-1
20-5
20-22
17-43
26-97
95
ii
0-215
49-9
20-6
20-26
17-53
26-965
ii
99
99
0-209
50-5
20-8
20-49
17-75
26-98
„
T54:
99
9/
0-207
Mean
0-209
Cryolite , A1 Na3 Fl6. Comminuted cryolite from
Greenland, smartly dried.
Experiments with Naphtha A.
Glass 2
!. Temperature of the Air 19°
•2-19°-5.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
50-6
21*5
21-21
18-44
grms.
26-975
grms.
5-55
grm.
1-775
0-431
grm.
0-453
0-243
50-0
21-5
21-15
18-43
26-965
,,
99
99
99
0-244
49-6
21-5
21-17
18-53
26-965
99
99
99
99
0-237
50-6
21-6
21-27
18-56
26-985
99
„
99
99
0-235
51-0
21-6
21-34
18-62
26-99
99
1-75*
„
„
0-232
Mean
0-238
55. Cyanide of Mercury, Hg C2 N2. Well-dried
crystals.
Experiments with Naphtha A. Glass 2.
Temperature of the Air
9°-2.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
45-2
o
11-2
10-86
8-34
grms.
26-935
grms.
6-555
grm.
1-955
0-431
grm.
0-487
0-100
47-0
11-5
11-23
8-62
26-965
99
99
99
99
0-098
49-5
11-7
11-43
8-64
26-955
99
99
99
0-099
43-7
11-5
11-22
8-84
26-95
„
1-94*
99
„
0-101
Mean
0-100
Cyanide of Zinc and Potassium , Zn K2 G4 N4. Distinct crystals. I made four series
of experiments with this substance.
Crystals dried in vacuo.
I. — Experiments with Naphtha A. Glass 2. Temperature of the Air ll°-8-ll°*5.
T.
T'.
t'.
t.
M.
m.
/•
V'
X .
sp. H.
44-9
13-8
13*53
11-13
grms.
26-96
grms.
2-515
grms.
2-195
0-431
grm.
0-487
0-257
48-0
13-9
13-64
11-13
26-93
ii
99
99
99
0-218
46-9
13-9
13-57
11-12
26-94
„
99
99
0-225
45-0
13-9
13-63
11-34
26-975
ii
2-175*
„
99
0-223
Mean . . . 0-231
* After drying the stopper.
138
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
II. — Experiments with Naphtha A. Glass 2. Temperature of the Air 12°-4-12°*3.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
O
o
o
o
grms.
grms.
grms.
grm.
45-5
14-5
14-15
11-83
26-97
2-465
2-225
0-431
0-487
0-232
46-7
14-5
14-22
11-74
26-97
„
99
99
99
0-256
45-2
14-3
13-96
11-72
26-945
99
2-17*
99
99
0-215
45-2
14-5
14-23
11-95
26-92
„
„
99
99
0-234
Mean . . . 0-234
Crystals dried at 100°.
III. — Experiments with Naphtha A. Glass 1. Temperature of the Air ll°-8-ll°-5.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
46-6
13-5
13-20
10-74
grms.
26-955
grms.
2-415
grm.
1-665
0-431
grm.
0-651
0-263
48-5
13-8
13-53
10-96
26-99
99
99
99
0-261
44-3
13-6
13-26
11-05
26-99
„
99
99
99
0-238
45-2
13-6
13-32
11-04
26-93
„
l-655f
99
99
0-240
Mean . . . 0-251
IV. — Experiments with Naphtha A. Glass 1. Temperature of the Air ll°-2-ll-3.
T.
o
T'.
o
t'.
o
t.
o
M.
grms.
m.
grms.
/•
grm.
V’
X.
grm.
sp. H.
49-4
13-3
13-04
10-43
26-94
2-255
1-78
0-431
0-651
0-235
46-7
13-4
13-11
10-62
26-98
99
99
99
„
0-266
49-2
13-6
13-33
10-72
26-955
99
99
99
55
0-247
48-0
13-5
13-22
10-73
26-97
99
l-765f „
Mean
55
0-237
0-246
The specific heat of cyanide of zinc and potassium between 14° and 46° is 0-241 as the
mean of the averages of the four series of determinations, 0-231, 0-234, 0-251, 0-246.
Crystallized Ferrocyanide of Potassium , Ee K4 G6 N6+ 3 H2 G. Fragments of air-dried
crystals.
Experiments with Naphtha A. Glass 1. Temperature of the Air 19°-2.
T.
T'.
t'.%
t.
M.
m.
/• y •
X.
sp. H.
o
O
o
o
grms.
grms.
grm.
grm.
50-6
21-3
21-03
18-46
26-98
3-425
1-69 0-431
0-651
0-288
51-3
21-1
20-82
18-22
26-98
99
99 99
99
0-275
51-0
21-0
20-74
18-14
26-97
99
99 99
99
0-280
51-0
21-1
20-84
18-26
26-965
99
l-675f „
Mean
99
0 278
0-280
* After removing some naphtha on the stopper,
t After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Ferridcyanide of Potassium, Fe K3 €6 N6. Well-formed crystals, smartly dried.
Experiments with Naphtha A. Glass 2. Temperature 13°*2.
T.
T'. t'.
o o
t.
o
M.
grins.
m.
grms.
/•
grms.
y •
X.
grm.
sp. H.
48-5
15-3 15-01
12-23
26*95
3-63
2-025
0*431
0*487
0*247
45-1
15-0 14-66
12-20
26-92
55
55
55
„
0*232
47T
15-5 15-23
12-68
26-975
55
55
55
55
0*225
44*4
15-3 15-00
12-64
26*98
55
2-015*
55
Mean
55
0*229
0*233
56. Nitrate of Soda, Na NG3. Crystallized salt, briskly dried.
Experiments with Naphtha A. Glass 2. Temperature of the Air 11°*8.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
O
o
o
grms.
grms.
grms.
grm.
47*2
14*3
13*95
11*02
26*91
3-645
2*25 0*431
0*487
0*258
46*2
14*9
14*55
11*82
26*945
55
55 55
,,
0*245
46*5
14*3
14-02
11*13
26*93
55
55 55
„
0*263
44*3
14*1
13-84
11*15
26*945
55
2-235* „
55
0*261
Mean . . . 0*257
Fused Salt.
Experiments with Naphtha A. Glass 1. Temperature of the Air 11°*8.
T.
o
T'.
o
t'.
o
t.
o
M.
grms.
m.
grms.
/•
grm.
y-
X.
grm.
sp. H.
47*8
13*9
13*62
10*57
26*98
3*92
1*66
0*431
0*651
0*271
43*9
14*3
14*03
11*43
26*065
,,
55
55
55
0*256
43*6
14*6
14*33
11*83
26*925
55
55
55
55
0*243
46-4
14*5
14*22
11*43
26*965
”
1*65*
Mean
55
0*254
0^
Nitrate of Potass , K N G3. Smartly dried crystallized salt.
Experiments with Naphtha A. Glass 1. Temperature of the Air 12°T-12°*4.
T.
T'.
t’.
t.
M.
m.
/•
y-
X.
sp. H.
44*2
o
14*2
13*88
11*43
grms.
26*93
grms.
3*105
grm.
1*845
0*431
grm.
0*651
0*242
46*5
14*4
14*14
11*56
26*99
55
55
0*233
45*6
14*3
14*03
11*53
26*97
55
55
55
0*228
44*7
14*0
13*74
11*31
26*98
55
1*83*
55
55
0*224
Mean . . . 0-232
After drying the stopper.
140
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Fused Salt.
Experiments with Naphtha A. Glass 2. Temperature of the Air 12°T-12°-4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
O
o
o
grms.
grms.
grms.
grm.
46-6
14-5
14-20
11-53
26-94
3-745
2-035
0-431
0-487
0-234
45-9
14-4
14-14
11-56
26-935
55
55
55
55
0-225
46-1
14-3
14-03
11-44
26-96-
55
55
55
55
0-222
44-7
14-1
13-83
11-32
26-96
55
2-02*
„
0-228
Mean . . . 0-227
57. Nitrate of Ammonia, N2H403. Vitreous transparent pointed crystals, like those
of nitre ; dried in vacuo over sulphuric acid.
I. — Experiments with Naphtha A. Glass 2. Temperature of the Air 10°-9.
T.
T'.
£.
t.
M.
m.
/•
y-
X.
sp. H.
o
32-3
12-7
12-43
10*53
grms.
26-92
grms.
2-555
grms.
2-41
0-431
grm.
0-487
0-424
31-1
12-8
12-52
10-66
26-945
55
55
55
55
0-475
29-2
12-6
12-33
10-63
26-92
55
55
55
55
0-482
33-5
13-1
12-81
10-74
26-93
55
2-405* „
55
0-473
Mean . . . 0-463
. — Experiments with Naphtha A. Glass 2. Temperature of the Air 140,4-15r
T.
T'.
t'.
t.
M.
m.
/• .
y-
X .
sp. H.
O
32-4
15-9
15-57
14-02
grms.
26-96
grms.
2-025
grms.
2-29
0-431
grm.
0-487
0-455
30-8
15-7
15-44
14-03
26-975
55
55
55
55
0-449
31-5
16-0
15-66
14-23
26-95
55
5 5
55
55
0-435
32-9
16-2
15-93
14-37
26-97
55
55
55
0-449
Mean . . . 0-447
The specific heat of nitrate of ammonia between 14° and 31° is as the mean of the
averages of both series of experiments, 0-463 and 0-447, = 0-455. The crystals were
quite unchanged at this temperature. In these experiments the difference of temperature
T — T' was but small, and it would not be surprising to find even greater deviations
among the individual results than are exhibited by the above numbers in the last
column. Nitrate of ammonia cannot be heated much above 30°, because it then
undergoes a molecular change, which apparently is accompanied by disengagement of
heat. This was observed in a series of experiments in which the heat was raised
to 45° or 48°; the crystals which, dried in vacuo , were originally of a vitreous
lustre and transparent, became, like the crystals dried at 100°, milky-white, porous.
* After drying the stopper.
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
141
and absorbent of naphtha. In these experiments the following numbers were
obtained.
Experiments with Naphtha A. Glass 2. Temperature of the Air 12°T-12°-4.
T.
T'.
t'.
t .
M.
m.
/•
y
X .
sp. H.
o
O
o
o
grms.
grms.
grms.
grm.
44-9
14-8
14-53
11-23
26-935
2-69
2-295
0-431
0-487
0-549
45-9
14-9
14-62
11-23
26-94
99
99
99
,,
0-546
47-6
14-6
14-32
10-70
26-925
99
2*445*
99
99
0-531
46-4
15-0
14-73
11-24
26-98
99
2-425f
99
0-545
The numbers for the specific heat of nitrate of ammonia are throughout greater
than those found between 14° and 31°; and probably because through the heating to
45° or 48° the change was set up during the experiments. Experiments with nitrate of
ammonia in which, by drying at 100°, this change had been effected before making the
experiments, gave numbers which more closely approach the first set, though somewhat
greater, and on the whole not very concordant. I obtained in a series of experiments
the following results with dull milky crystals dried at 100°.
Experiments with '
Naphtha A. Glass 1.
Tempe:
rature
of the Air 9°-7.
T.
T'.
t\
t.
M. m.
/.
y-
X.
sp. H.
O
O
o
o
grms. grms.
grms.
grm.
45-0
12-3
11-95
8-96
26-975 '2-03
1-77
0-431
0-651
0-519
45-6
12-3
12-03
9-01
26-935
33
99
„
0-507
44-9
12-6
12-26
9-32
26-965
1-90*
99
99
0-485
45-1
12-5
12-24
9-31
26-98
33
99
99
0-470
45-4
12-6
12-33
9-32
26-965 „
2-08$
99
99
0-457
Crystals dried at 100°-110°, which apparently had been softened, gave the
following numbers.
Experiments with Naphtha A. Glass 1. Temperature of the Air 12°T-12°-4.
T.
T\
t'.
t.
M.
m. /. y.
x. sp. H.
O
0
o
0
grms.
grms. grms.
grm.
44-6
14-2
13-93
11-03
26-97
2-095 1-91 0-431
0-651 0-524
43-6
14-4
14-13
11-42
26-935
99 99 99
„ 0-489
47-8
14-8
14-54
11-44
26-975
„ 2-04* „
0-479
46-5
14-6
14-32
11-23
26-96
„ 2-02f „
„ 0-520
I do not know the nature of the change which nitrate of ammonia undergoes fust
above 40°.
* After adding some naphtha. t After drying the stopper. $ After more naphtha.
142 PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
58. Nitrate of Strontia, Sr N2 06. Crystallized, dried at 100°.
Experiments with Naphtha A. Glass 3. Temperature of the Air 14°*9-16°-0.
T.
T'.
t\
t.
M.
m.
/•
y-
CC.
sp. H.
O
o
o
o
grms.
grms.
grms.
grm.
46-0
16-6
16-33
13-95
26-955
4-575
2-10
0-431
0-453
0-180
46-8
17-1
16-83
14-43
26-95
*9
99
99
99
0-179
46-7
17-1
16-84
14-44
26-935
99
99
99
99
0-180
47-9
17-2
16-93
14.43
26-975
99
2-085*
„
„
0-185
Mean . . . 0T81
Nitrate of Baryta, Ba N2 06. Crystals dried at 100°.
Experiments with Naphtha A. Glass 2. Temperature of the Air 130,3-1 3°*4.
T.
o
T'.
o
t'.
o
t.
o
M.
grms.
m.
grms.
/•
grms.
y-
X.
grm.
sp. H.
48-7
15-3
15-23
12-52
26-98
4-995
2-255
0-431
0-487
0-149
48-5
15-4
15-13
12-43
26-985
99
99
99
„
0-149
47-1
15-5
15-23
12-72
26-955
99
99
„
0-137
46-1
15-6
15-32
12-85
26-95
99
2-24*
99
Mean
55
0-146
(KL46
Nitrate of Lead, Bb N2 06. Crystals dried at 100°.
Experiments with Naphtha A. Glass 1. Temperature of the Air 13°-3-13°-4.
T.
T'.
t\
t.
M.
m.
/• y.
X.
sp. H.
o
O
o
0
grms.
grms.
grm.
grm.
46-8
15-7
15-35
12-73
26-925
7-955
1-675 0-431
0-651
0-113
48-2
15-8
15-53
12-82
26-98
99
99 99
0-111
48-1
16-1
15-83
13-22
26-965
99
99 99
0-104
45-0
15-9
15-57
13-15
26-99
99
1-655* „
Mean
55
0-111
0-110
59. Chlorate of Potass, K C103. Pure well-dried crystals.
Experiments with Naphtha A. Glass 1. Temperature of the Air 16°-4-17°-3.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
50-6
18-4
18-12
15-63
grms.
26-97
grms.
2-485
grms.
2-18
0-431
grm.
0-651
0-199
50-0
18-6
18-25
15-83
26-945
99
99
99
0-196
48-3
18-8
18-45
16-22
26-95
99
99
99
0-180
48-4
18-8
18-53
16-24
26-96
„
2-165*
99
99
0-202
Mean . . . 0-194
* After drying the stopper.
PKOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
143
Crystallized Chlorate of Baryta, Ba Cl2 06+H2 O. Crystalline crusts, dried in vacuo.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°*3-14°*4.
T.
T'.
t'.
t.
M.
m. /.
y-
X.
sp. H.
Q
o
0
o
grms.
grms. grms.
grm.
46*7
16*1
15*83
13*53
26*97
3*02 2*135
0*431
0*651
0*151
46*2
16*2
15*92
13*62
26*915
99 99
99
99
0*163
46*5
16*1
15*76
13*45
26*95
99 99
99
99
0*158
46*5
16*1
15*83
13*53
26*99
„ 2*13*
0*157
Mean . . . 0*157
Perchlorate of Potass, K Cl 04. Well-formed crystals.
Experiments with Naphtha A. Glass 2.
T. T'. t'. t. M. m.
o o o o grins. grms.
46*6 13*7 13*43 11*02 26*93 3*205
45*7 13*6 13*33 10*94 26*98
44*9 13*7 13*43 11*10 26*955
44*0 13*6 13*33 11*04 26*945
Temperature of the Air 11°*5.
y. x. sp. H.
/•
grms.
2*115
2*095*
X.
grm .
0*431 0*487 0*179
„ „ 0*190
„ „ 0*192
„ „ 0*199
Permanganate of Potass, K Mn 04. Crystals.
Experiments with Naphtha A. Glass 1. Temperature of the Air 11°*5.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
o
0
o
grms.
grms.
grm.
grm.
44*3
13*7
13*43
11*02
26*955
3-655
1*83
0*431
0*651
0T87
45*6
13*7
13*43
10*94
26*955
99
99
99
99
0*181
46*0
13*8
13*51
11*03
26*99
99
99
99
0*175
46*2
13*7
13*44
10*95
26*935
99
1*815*
99
99
0*173
Mean . . . 0*179
60. Metaphosphate of Soda, NaP03. Prepared as a transparent vitreous mass by
igniting phosphate of soda and ammonia.
Experiments with Naphtha A. Glass 2. Temperature of the Air 14°*4-14°*5.
T.
T'.
t'.
t.
M.
m.
/•
y-
x. sp. H.
o
o
0
o
grms.
grms.
grm.
grm.
49*1
16*7
16*37
13*54
26*92
4*70
1*845
0*431
0*487 0*227
48*3
16*8
16*45
13*75
26*975
99
99
99
„ 0*219
43*1
16*5
16*23
13*96
26*92
99
„ 0*216
43*3
16*7
16*44
14*23
26*935
99
1*83*
99
„ 0*205
Mean . . . 0*217
* After drying the stopper.
MDCCCLXV.
X
144
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Phosphate of Silver , Ag3PG4: yellow powder dried at 110°. This substance, in
the quantity I used, is but ill fitted for procuring accurate results. I have made two
series of experiments with it, but the results obtained thereby are only to be considered
as rough approximations.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 20°-5-20o,8.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
O
0
o
0
grms.
grms.
grms.
grin.
51-4
22-5
22-19
20-16
26-99
3-775
2-105 0-431
0*651
0-0895
52-0
22-4
22-14
20-12
26-955
33
33 3?
33
0-07451
51-5
22-5
22-16
20-13
26-965
33
33 33
33
0-0872
51-5
22-5
22-15
20-14
26-985
„
2-095* „
33
0-0839
Meanf . . . 0-0869
II. — Experiments with Naphtha A. Glass 3. Temperature of the Air 16°-3-16°-6.
T.
T'.
t'.
t.
M.
m.
/•
y-
00.
sp. H.
o
0
o
grms.
grms.
grms.
grm.
51-1
18-4
18-12
15-72
26-955
4-545
2-555
0-431
0-453
0-0933
51-5
18-4
18-13
15-73
26-995
33
53
,,
„
0-0887
51-8
18-5
18-22
15-76
26-94
33
33
33
33
0-0959
51-6
18-6
18-33
15-93
26-98
33
2-54*
33
33
0-0911
Mean . . . 0-0923
The mean of both these means gives 0 0896 as the specific heat of phosphate of
silver. This number, as already remarked, is but little trustworthy. But it may be
concluded from these experiments that the specific heat of phosphate of silver cannot
differ much from 0-09.
Phosphate of Potass, K H2P 04. Clear crystals dried at 110°.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°-9-16o,0.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
46-8
16-9
16-56
14-21
grms.
26-96
grms.
3-95
grm.
1-575
0-431
grm.
0-651
0-200
48-0
17-2
16-89
14-43
26-965
33
33
33
33
0-209
47-5
17-4
17-09
14-71
26-96
33
33
33
33
0-203
48-0
17-2
16-92
14-43
26-995
33
1-56*
33
33
0-218
Mean . . . 0-208
* After drying the stopper.
f Excluding the second experiment.
PROFESSOR KOPP GIST THE SPECIFIC HEAT OF SOLID BODIES.
Arseniate of Potass, KH2As 04. Clear crystals dried at 105°.
Experiments with Naphtha A. Glass 2. Temperature of the Air 14°*3-14°*4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
0
0
0
grms.
grms*
grms.
grm.
47*1
16*2
15*93
13*43
26*96
4*455
2*05
0*431
0*487
0*182
47*5
16*2
15*92
13*43
26-975
99
99
99
0*174
45*1
16*1
15*84
13*54
26*955
„
99
99
99
0*172
45*5
16*3
16*01
13*70
26*955
„
2*045*
99
99
0*172
Mean . . . 0-175
61. Carbonate of Soda, Na2 G 03. Fused salt.*
Experiments with Naphtha A. Glass 2. Temperature of the Air 150-5.
T.
T'.
G
t.
M.
m.
/• .
y ■
a?.'
sp. H.
o
0
o
o
grms.
grms.
grms.
grm.
48*0
17*7
17*35
14*54
26*935
4*575
2*08
0*431
0*487
0*244
47*9
17*7
17*43
14*63
'26*95
99
99
?5
0*244
48*1
17*7
17*40
14*53
26*985
. .
99
99
0*254
48-1
17*7
17*43
14*63
26*965
99'
2*055
*
99 *
„ '
0*243
Mean . . . 0*246
Carbonate of Potass, K2 C03. Fused salt.
Experiments with Naphtha A.
Glass 1.
Temperature
of the
Air 15°*
T.
T'.
t'.
t.
M.
TO. /.
X»
sp. H.
O
o
o
o
grms.
grms. grm.
grm.
47*4
.17*4
17*14
14*75
26*975
3*045 1*96
0*651
0*215
47*5
17*4
17*12
14*73
26*975
99 99
99
0*212
47*3
17*4
17*14
14*82
26*95
99 95
99
0*196
45*6
17*5
17*21
15*02
26*96
„ 1*95*
99
0*200
Mean .
0*206
Carbonate of Bubidium, Rb2 €03. Fused salt.
Experiments with Naphtha A. Glass 2. Temperature of the Air 150-5.
T.
T'.
t'.
t.
M.
m.
/•
X.
sp. H.
o
O
0
o
grms.
grms.
grm.
grm.
49*3
17*7
17*38
14*80
26*965
6*855
1*95
0*431
0*487
0*127
47*1
17*4
17*13
14*70
26*955
99
99
99
0*128
46*8
17*6
17*33
14*94
26*97
99
99
99
0*128
45*8
17*6
17*33
15*16
26*93
99
1*93*
„
0*110
Mean . . . 0*123
* After drying the stopper.
146
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
62. Carbonate of Lead, Pb C03. Cerussite from Washington mine, Davidson county,
North Carolina : beautiful clear crystals.
Experiments with Naphtha A. Glass 1. Temperature of the Air 130,8.
T.
T'.
t'.
t.
31.
m.
/•
y*
X.
sp. H.
49-2
103
16*03
13-16
grms.
26-95
grms.
11-42
grm.
1-90
0-431
grm.
0-651
0-0772
49-8
16-0
15-68
12-72
26-94
55
55
55
??
0-0779
47-4
15-9
15-60
12-80
26-94
55
55
55
„
0-0810
46-5
15-9
15-64
12-94
26-97
55
55
55
?>
0-0797
43-2
15-8
15-55
13-14
26-96
„
1-885*
??
0-0795
Mean . . . 00791
Carbonate of Lime , €a C03. I have investigated both the rhombic and the rhom-
bohedral modification.
Arragonite. Fragments of clear crystals from Bilin, in Bohemia
Experiments with Naphtha A. Glass 1. Temperature of the Air 13°*8.
T.
o
T\
o
t'.
o
t .
o
31.
grms.
m.
grms.
A
grm.
y-
X.
grm.
sp. H.
51-1
16-8
16-53
13-25
26-965
6-445
1-94
0-431
0-487
0-195
46-6
16-0
15-70
12-73
26-98
??
55
55
??
0-201
45-8
16-1
15-83
12-94
26-975
?!
55
??
0-216
44-0
16-0
15-74
13-03
26-965
„
55
55
„
0-200.
44-3
15-9
15-63
12-86
26-955
??
1-92*
55
Mean
??
0-204
0-203
Calcareous Spar. Cleavage pieces of transparent specimens from Auerbach, on the
Bergstrasse.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°-4-14°-7.
T.
T'.
t'.
t.
31.
m.
/■
y-
cc.
sp. H.
o _
O
0
o
grms.
grms.
grm.
grm.
49-5
15-5
15-24
12-13
26-98
5-425
1-48
0-431
0-651
0-217
49-6
16-3
15-96
13-00
26-96
55
55
55
0-204
48-2
16-1
15-83
12-94
26-915
55
55
55
55
0-209
45-2
16-2
15-94
13-42
26-93
55
1-465*
„
55
0-195
Mean . . . 0-206
After drying the stopper.
PEOFESSOB KOPP OX THE SPECIFIC HEAT OF SOLID BODIES.
147
63. Magnesian Spar, Ca^ Mgi C03*. Specimens of magnesian spar from the Zillerthal.
Experiments with Naphtha A. Glass 3. Temperature of the Air 15°T-15°*9.
T.
T.
f.
t.
IT.
m, .
/• y.
X.
sp. H.
c
0
o
grms.
grms.
grm.
grm.
48*9
17*7
17*43
14*52
26*96
6*195
1*76 0*431
0*453
0*210
48*3
17*9
17*60
14*77
26*96
55
55 55
55
0*210
47*0
17*9
17*64
15*02
26*995
1*745 f ,,
0*198
Mean . . . 0*206
Spathic Iron, -F Mn^ Mg^ C03$ . Cleavage pieces of reddish crystals from Bieber,
Hesse Cassel.
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°*6-14°*4.
T.
T.
t'.
t.
11.
m .
/• y-
X .
sp. H.
o
O
0
o
grms.
gnus.
grm.
grm.
47*7
17*0
16*74
13*92
26*98
6*56
1*78 0*431
0*651
0*162
45*6
16*9
16*63
13*94
26*93
„
55 55
55
0*169
46*1
16*9
16*55
13*83
26*965
1*765 f „
0*168
Mean . . . 0*166
64. Zircon, ZrSi04, or Irh SL 0.,. Hyacinth crystals from Ceylon.
Experiments with Naphtha A. Glass 1. Temperature of the Air 18c*4-19°*8.
T.
T-
t\
t.
ll.
rn.
/• y-
sp. H.
o
o
o
o
grms.
grms.
grm.
grm.
51*2
20*6
20*33
17*46
26*945
9*69
1*32 0*431
0*651 0T35
50*2
20*8
20*54
17*83
26*955
55
55 55
„ 0*131
51*0
21*0
20*74
18*01
26*97
55 55
„ 0*127
52*0
21*2
20*87
18*03
26*96
55
55 55
„ 0*131
51*1
21*3
21*03
18*24
26*93
55
l*30f „
„ 0*135
Mean . . . 0*132
* The results of my analysis of this spar (Ann. der Chem. nnd Pharm. Ixxxi. 50) are, compared with the
numbers required by the above formula, as follows : —
CaO COs. ITgOCO,. FeO CO/. Total.
Found 54-3 42-2 37 100-2
Calculated .... 54-3 45-7 „ 100-0
t After drying the stopper.
X The numbers found in my analysis of this spathic iron (Ann. der Chem. nnd Pharm. Ixxxi. 51) are given
below, compared with those calculated on the above formula.
FeO C02. HhO C02. CaOCO,. Mg0C02. Xb. Total.
Found 73-7 19-0 0-9 6-6 0-7 100-9
Calculated .... 74-7 18-6 ,, 6-7 „ 100-0
“With some HnO C03.
b Insoluble in aqua regia.
148
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Chrysolite , Mg^. -Fe^. Si04*. From Dockweiler in the Eifel. Transparent to trans-
lucent bright green crystalline fragments.
Experiments with Naphtha A. Glass 1. Temperature of the Air 190,2-19°-5.
T.
T.
t'.
t.
M. m. f.
y •
so.
sp. H.
G
grms. grms. grm.
grm.
5P3
21-4
21-14
18-53
26-985 5-84 1-475
0-431
0-657
0-183
50-4
21-4
21-13
18-55
26-965 „
55
55
0T91
50-9
21-5
21-17
18-54
26-985 „
55
9?
0-193
50-9
21-5
21-16
18-55
26-96
55
0-189
49-9
21-4
21-13
18-63
26-975 „ l-45f
„
99
0-187
Mean
0-189
Olivine , Mg* » Fe^ Si 04 J,
, From
a spheroidal mass surrounded by lava from the Eifel.
Experiments with Naphtha A.
Glass 1. Temperature of the Air 190,
0-19°-6.
T.
T'.
t'.
t.
M. m. /.
y-
X ,
sp. H.
0
o
0
o
grms, grms. grm.
grm.
51-5
21-6
21-26
18-53
26-975 6-37 1-425
0-431
0-651
0-188
51-4
21*3
-20-97
18-22
26-975
,,
59
0-188
51-5
21-6
21-25
18-52
26-975 „
55
0T88
52-1
21-8
21-52
18-72
26-97 „ 1-41 f
„
99
0-194
Mean
0-187
65. Wollastonite,
€a Si G;
5. Pure
j pieces of Wollastonite from Finnland.
Experiments with Naphtha A. Glass 1. Temperature of the Air 17°*2.
T. T'.
t'. t.
M.
m. f.
y. x.
sp. H.
O O
o o
grms.
grms. grm.
grm.
51-0 19-4
19-12 16-33
26-955
5-31 1-81
0-431 0-651 0-179
50-5 19-1
18-76 16-01
26-945
5-9 5 9
55 55
0-175
50-0 19-2
18-92 16-19
26-98
95 95
55 55
0-181
50-7 19-4
19-13 16-40
26-97
l-785f „
0-176
Mean . .
. 0-178
* An analysis by Professor Knop gave tbe
following
results, which are collated with the numbers required
by the above formula
SiOs.
MgO.
FeO.
Ah03.
Total.
Found
40-95
50-82
8-83
trace
100-60
Calculated
.... 41-15
49-87
8-98
39
100-00
t After drying the stopper.
t This olivine has
the same composition
as the above chrysolite.
Professor Knop found for this olivine
the following numbers, which are compared with those required by the above formula
Si02.
MgO.
FeO.
A1203.
Total.
Found ...
41-85
49-10
8-75
trace
99-70
Calculated
.... 41-15
49-87
8-98
100-00
PROFESSOR EOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
149
Diopside, Mgj Si 03. Fragments of a greenish and white crystal of the charac-
teristic aspect of the diopside from Schwarzenstein in the Tyrol.
Experiments with Naphtha A. Glass 1. Temperature of the Air 16°’3-160-5,
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
G
o
0
o -
grms.
grms.
grin.
grin.
48-1
18-7
18-42
15-65
26-99
6-17
1-55
0-431
0-651
0-186
49-4
18-4
18-13
15-22
26-98
55
55
55
0-185
51-8
18-6
18-25
15-13
26-98
55
55
55
0-185
50-8
18-8
18-54
15-53
26-925
55
1-53*
55
55
0-186
Mean . . . 0-186
Diqptase, €uSi03-j-H2O. Eine crystals from the Kirgisensteppe.
Experiments with Naphtha A. Glass 3. Temperature of the Air,16°-7-T6°-4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
49-8
18-9
18-63
16-04
grms.
26-94
grms.
5-545
grm.
1-80
0-431
grm.
0-453
0-186
50-3
19-1
18-76
16-17
26-95
55
55
55
5?
0-182
50-3
18-9
18-64
16-05
26-99
55
55
55
0-180
48-5
18-9
18-5.8 :
16T3
26-945
55
1-79*
55
55
0-181
Mean . . . 0-182
Qrthoclase, Al2 K2 Si6 016. Cleavage pieces of a flesh-coloured reddish orthoclase from
Aschaffenburg.
Experiments with Naphtha A. Glass 3. Temperature of the Air 18°‘4-19°T.
T.
T'.
t\
t.
M.
m.
/• y-
X.
sp. H.
0
O
0
o
grms.
grms.
grm.
grm.
50-6
20-2
19-86
17-42
26-945
5-185
1-78 0-431
0-453
0-182
49-6
20-3
20-00
17-63
26-95
55
55 55
„
0-185
51-1
20-5
20-15
17-71
26-94
55
55 55
55
0-179
51-2
20-5
20-21
17-73
26-965
55
1*77* „
55
0-186
Mean . . . 0-183
Albite, Al2 Na2 Si6 0i6. Fragments of white crystals from Pfunders, in Tyrol.
Experiments with Naphtha A. Glass 3. Temperature of the Air 180-7-19°-8.
T.
T'.
t\
t.
M.
m.
/• y-
X .
sp. H.
o
0
o
o
grms.
grms.
grm.
grm.
52-4
20-3
20-04
17-44
26-955
4-835
1-84 0-431
0-453
0-194
50-7
20-8
20-53
18-14
26-975
55
55 55
0-188
50-1
20-9
20-63
18-30
26-935
55
55 55
55
0-187
52-0
21-1
20-82
18-33
26-955
55
55 55
55
0-192
50-4
21-3
21-04
18-73
26-97
„
T82* „
55
0-187
Mean . . . 0-190
* After drying the stopper.
150
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
66. Borate of Soda, Na2B407. Beautiful transparent vitreous pieces of fused borax.
Experiments with Naphtha A. Glass 2. Temperature of the Air 140,4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
0
o
o
grms.
grms.
grms.
grm.
46-6
16-6
16"33
13-67
26-95
4.475
2-005
0-431
0-487
0-232
46-8
16-6
16-33
13-65
26-98
99
99
„
0-233
46-5
16-6
16-33
13-73
26-965
99
,,
0-222
46-6
16-8
16-54
13-93
26-945
99
1-99*
„
,,
0-227
Mean . . . 0-227
Hydrated Borate of Soda, Na2 B4 07+lO H2 0. Crystallized borax dried in the air.
Experiments with Naphtha A. Glass 3. Temperature of the Air 16°-3-160-5.
T.
T'.
t'.
t.
M.
m.
/■
y •
X.
sp. H.
50-9
18-7
18-43
15-43
grms.
26-98
grms.
3-38
grm.
1-745
0-431
grm.
0-453
0-387
50-3
18-4
18-13
15-15
26-95
99
99
99
0-388
49T
18-5
18T6
15-33
26-96
99
99
99
99
0-381
49-5
18-8
18-45
15-61
26-945
99
1-73*
99
99
0-383
Mean . . . 0-385
67. Tungstate of Lime, Ca W04. Crystals of Scheelite from Zinnwald in Bohemia.
Experiments with Naphtha A. Glass 1. Temperature of the Air 16°-7-16°-4.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
o
o
o
grms.
grms.
grm.
grm.
50-3
19-3
19-00
16-27
26-96
11-575
1-34 0-431
0-651
0-0990
49-5
19T
18-84
16-22
26-96
99
99 99
99
0-0946
50-5
19-0
18-71
15-94
26-97
99
99 99
99
0-0988
48-6
19-0
18-66
16-12
26-99
99
1-325* „
99
0-0945
Mean . . . 0-0967
Wolfram, Fe§ Mn* W04f. Fragments of crystals from Altenberg in the Erzgebirge.
Experiments with Naphtha B. Glass 1. Temperature of the Air 19°T-19°-0.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
0
o
0
o
grms.
grms.
grm.
grm.
52-1
21-1
20-83
18T4
26-985
11-455
1-525
0-419
0-651
0-0918
52-9
21-2
20-92
18-14
26-975
5?
99
99
99
0-0939
54-0
21-2
20-92
18-04
26-97
99
0-0941
54-8
21-4
21-13
18-23
26-945
„
1-51*
99
99
0-0921
Mean . . . 0-0930
*■ After drying the stopper.
t According to Kerndt’s analysis of. the wolfram of Altenberg (Rammelsberg’s ‘ Handbuch der Mineral.
Ohemie,’ p. 308).
PEOFESSOE K.OPP ON THE SPECIFIC HEAT OF SOLID BODIES.
151
Molybdate of Lead , Pb M 04. Comminuted crystals of Wiilfenite (Gelbbleierz) from
Bleiberg in Carinthia.
Experiments with Naphtha A. Glass 3 Temperature of the Air 17°-6-17°-4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
50-2
19-3
18-95
16-45
grms.
26-98
grms.
8-69
grms.
2-32
0-431
grin.
0-453
0-0840
50-0
19-2
18-92
16-43
26-97
55
55
??
„
0-0837
48-6
19-1
18-84
16-47
26-935
55
5T
55‘
>»
0-0818
49-3
19-3
19-01
16-62
26-98
„
2-295* „
55
0-0814
Mean . . . 0-0827
68. Chromate of Lead, Pb €r G4. For the investigation pieces of artificially prepared
chromate of lead were used, which after fusion had solidified to an aurora-red mass of a
fibrous crystalline structure, and with crystal needles on the surface.
Experiments with Naphtha A. Glass 3. Temperature of the Air 17°T-17°’9.
T.
T'.
t'.
t.
M.
m.
A U’
X.
sp. H.
o
o
0
0
grms.
grms.
grm.
grm.
50-0
19-0
18-74
16-22
26-975
10-60
1-93 0-431
0-453
0-0857
50-1
19-2
18-92
16-34
26-985
55
55 55
55
0-0931
49-6
19-2
18-93
16-42
26-975
55
55 55
55
0-0889
49-9
19-3
19-02
16-44
26-99
55
1-915* „
55
0-0940
Mean .
0-0900
Chromate
of Potass, K2 Cr G4.
Crystals
of the neutral salt dried
at 105°
Experiments with Naphtha A. Glass
1. Temperature of the
Air 16c
•l-16°-8.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
o
0
o
grms.
grms.
grm.
grm.
49-1
18-0
17-69
15-13
26-985
4-995
1-535 0-431
0-651
0-182
45-7
17-8
17-49
15-14
26-975
55
55 55
„
0-192
47-3
17-9
17-62
15T3
26-995
55
55 55
55
0-195
48-2
18-2
17-93
15-43
26-955
»
1-525* „
55
0-188
Mean . . . 0-189
Acid Chromate of Potass, K2 Cr2 G7 Crystals of the so-called bichromate.
Experiments with Naphtha A. Glass 1. Temperature of the Air 19°T-19°'5.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
o
o
o
o
grms.
grms.
grm.
grm.
53-3
21-1
20-83
18-33
26-97
4-275
1-58
0-431
0-651
0-178
51-5
21-1
20-82
18-42
26-95
5 5
„
55
55
0-186
51-6
21-1
20-76
18-33
26-96
55
55
55
„
0-191
52-6
21-2
20-93
18-45
26-975
55
1-555*
„
55
0T89
Mean . . . 0T86
* After drying tlie stopper.
T
MDCCCLXV.
152
PKOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
69. Sulphate of Soda, Na2 S04. Crystalline crusts briskly dried.
Experiments with Naphtha A. Glass 1. Temperature of the Air 110,2-110,4.
T.
T.
t’.
t.
M.
m.
/• y-
X.
sp. H.
O
o
o
0
grms.
grms.
grm.
grm.
44-2
12-8
12-52
9-94
26-97
3-465
1-73 0-431
0-651
0-236
47*8
13-2
12-93
10-14
26-93
59
95 55
0-224
46*1
13-2
12-93
10-25
26-95
59
95 99
„
0-230
46-6
13-6
13-32
10-69
26-975
55
1-716* „
Mean
”
0-219
0-227
Sulphate of Potass , K2 S04. Crystal crusts sharply dried.
Experiments with Naphtha A. Glass 2. Temperature of the Air ll°*2-ll0-4.
T.
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
0
o
<3
grms.
grms.
grms.
grm.
44-5
12-7
12-44
12-02
26-915
3-405
2-145 0-431
0-487
0-187
47-0
13-2
12-93
10-22
26-95
„
2-30f „
0-200
45-9
13-3
13-02
10-41
26-95
99
55 95
„
0-200
43-1
13-3
13-03
10-67
26-95
2-275* „
Mean
59
0-196
0-196
Acid Sulphate of Potass, KH S04. Well-formed crystals dried at 100° J. The salt
became feebly red on the surface in contact with the coal-tar naphtha.
cperiments with Naphtha A.
Glass 1.
Temperature of the Air 17°
•0-17°-
T.
T'.
t\
t.
M.
m.
/• y-
X.
sp. H.
o
o
o
o
grms.
grms.
grm.
grm.
50-7
19-4
19-12
16-43
26-94
3-445
1-85 0-431
0-651
0-251
50-4
19-3
19-01
16-36
26-945
95
55
0-245
50-5
19-3
18-97
16-34
26-96
5? J?
59
0-239
51-9
19-4
19-05
16-32
26-965
59
1-83* „
Mean
55
0-239
0-244
70. Sulphate of Ammonia, N2 H8 S04. I made two series of experiments with this salt.
Crystals dried in vacuo over sulphuric acid.
I. — Experiments with Naphtha A. Glass 2. Temperature of the Air 10o,9-llo,3.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
o
o
o
0
grms.
grms.
grm.
grm.
45-1
13-0
12-73
9-73
26-93
3-425
1-825
0-431
0-487
0-363
44-5
13-4
13-12
10-25
26-98
??
59
59
99
0-355
44-3
13-2
12-93
10-08
26-93
1-815* „
55
0-350
Mean
0-356
* After drying the stopper. + After adding some naphtha.
$ Dr. Engelbach found the quantity of potass in these crystals to be 33'70 and 34-13 per cent. Calculated
from the above formula 34-61 per cent, are required.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
153
Crystals dried at 120°.
II. — Experiments with Naphtha A. Glass 1. Temperature of the Air 10°'9-llo,31.
T.
T'.
t'.
t.
M.
m.
/•
&
X.
sp. H.
O
0
0
o
grms.
grms.
gnu.
grm.
44-2
12-9
12-63
9-97
26-94
2*84
1*555
0-431
0-661
0-341
42-2
12-6
12-33
9-81
26-95
T. )
*5
r)
55
0-343
45-4
13-3
12-96
10-30
26-985
55
55
55
55
0-322
46-7
13-0
12-72
9-77
26-935
„
1-535*
55
55
0-368
Mean . . . O' 344
The mean of the means of both series of experiments, 0-356 and 0-344, gives for the
specific heat of sulphate of ammonia between 13° and 45° the number 0-350f.
71. Sulphate of Lead, Bb£G4. Fragments of transparent crystals of lead- vitriol
from Miisen, near Siegen.
Experiments with Naphtha A. Glass 1. Temperature of the Air 17°-6-17°*4.
T.
O
T'.
o
t'.
t.
O-
M.
grms.
m.
grms.
/•
grm.
y-
X*
grm.
sp. H.
48-3
19-6
19-33
16-90
26-975
12-575
1-47
0-431
0-651
0-0795
50-9
19-3
19-00
16-23
26-96
55
55
55
55
0-0858
49-9
19-3
19-01
16-33
26-985
„
55
55
0-0858
50-4
19*6
19-24
16-63
26-99
55
1-45*
55
Mean
55 *'
0*0798-
0-0827
Sulphate of Baryta , Ba S04. Cleavage pieces of crystal of heavy spar from the
Auvergne.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 15°T-150,9.
T.,
T'.
t'.
t.
M.
m.
/• y-
X.
sp. H.
o
0
o
o
grms.
grms.
grm.
grm.
46-5
17-4
17-12
14-64
26-945
9-15
1-405 0-431
0-651
0-113
48-5
17-5
17*17
14-56
26-97
55
55 55
5?
0-111
44-6
17-4
17-05
14-82
26-97
55
1-395* „
Mean
55
0-105
0*110
* After drying the stopper.
t I had made a third series of experiments with large dry transparent crystals of sulphate of ammonia, but
in which t' exceeded more than usual the temperature of the air, and hence numbers were found for the body
investigated which are somewhat too small.
Experiments with Naphtha A. Glass 2.. Temperature of the Air 9°-7.
t:
T'
t'.
U
M.
w.
/•
&
X.
sp^ H.
45-6
O
12-4
12-05
8-86
grms.
26-935
grms.
3-725
grms.
2-015
0-431
gnn.
0-487
0-331
47-1
12-8
12-45
9-22
26-97
„
„
,,
0-318
42-9’
12-6
12-25
9-42
26-99
„
„
55
,,
0*313
44-1
12-5
12-22
9-24
26-95
,,
„
>>
55*
0-318
47-0
12-7
12-36
9-16
26-94
„
1-985®
,r
0-314
® After removing some naphtha from the stopper.
Y 2
154
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
XX.— -Experiments with Naphtha A. Glass 1. Temperature of the Air 160'7-17°-2.
T.
T',
t'r
t.
M.
m.
/•
y-
X.
sp. H.
O
o
o
o
grms.
grms.
grin.
grni.
49-9
19-0
18-65
16-13
26-96
7-77
1-68
0-431
0-651
0-106
50*9
19-0
18-74
16-14
26-94
55
55
55
0-106
49-0
19-0
1067
16-22
26-96
„
1-665*
55
„
0-107
Mean . . . 0T06
The mean of the means of these two sets of experiments gives 0T08 for the specific
heat of heavy spar between 18° and 44°.
Sulphate of Strontia, Sr S04. Crystals of celestine from Dornburg, near Jena.
Experiments with Naphtha A. Glass 3. Temperature of the Air 150,6-16°T.
T.
T'.
t'.
t.
M.
m.
/•
V‘
X .
sp. H.
O
O
o
0
grms.
grms.
grm.
grm.
50-2
17-8
17-47
14-74
26-965
7-63
1-90
0-431
0-453
0-137
50-5
T7-7
17-43
14-64
26-955
55
55
0-134
51-4
17 -8
17-51
14-64
26-995
>5
55
„
0-135
52-7
17-9
17-55
14-61
26-955
55
1-875*
„
„
0-133
Mean . . . 0T35
72. Sulphate of Lime, CaS04. Small crystalline pieces of anhydrite.
I. — Experiments with Naphtha A. Glass 1. Temperature of the Air 130,2-13°*7.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
46-1
15-6
15-33
12-72
grms.
26-98
grms.
5-305
grm.
1-715
0-431
grm.
0-651
0-173
46-5
15-5
15-22
12-53
26-93
55
55
55
55
0-178
45-7
15-6
15-34
12-74
26-92
55
55
55
„
0-176
43-6
15*7
15-44
13-11
26-94
v
1-70*
55
55
0-163
Mean .
0-173
II. — Experiments with
Water.
Glass
3. Temperature of the
Air 17'
3-9-18°-3.
T.
T'.
t'.
t.
M.
m.
/•
V'
X.
sp. H.
47-5
19-9
19-62
15-62
grms.
26-95
grms.
5-62
grms.
2-415
1-000
grm.
0-453
0-185
47T
19-8
19-53
15-61
26-99
55
55
„
0-179
47-1
20-1
19-77
15-87
26-975
55
55
55
0-183
47-5
20-2
19-94
16-03
26-98
55
2-40*
0-180
Mean . . . 0T82
The average of the means of these determinations gives 0T78 as the specific heat of
anhydrite between 18° and 46°.
After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
155
Hydrated Sulphate of Lime, GaSG4+2 H2 O. Cleavage pieces of transparent Gypsum
from Reinhardtsbrunn, in Thuringen.
Experiments with Naphtha A. Glass 2. Temperature of the Air 13°-2-13°-7.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
47-2
15-6
15-29
12-32
grms.
26-94
grms.
4-335
grms.
2-115
0-431
giro.
0-487
0-261
47-4
15-8
15-53
12-57
26-99
„
99
99
5)
0-261
45-7
15-8
15-53
12-73
26-96
99
99
99
„
0-260
44-2
16-0
15-73
12-13
26-94
99
2-095*
99
5?
0-252
Mean . . . 0-259
73. Crystallized Sulphate of Copper , Gu SG4-J-5 H20. Crystals of Blue vitriol dried
in the air.
xperiments with Naphtha A.
Glass
1. Temperature of the Air 14c
•1-14°-
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
0
o
o
grms.
grms.
grm.
grm.
50-8
16-4
16-08
12-82
26-99
4-12
1-65
0-431
0-651
0-290
47-3
16-4
16-05
13-12
26-965
99
99
„
„
0-290
46-7
16-5
16-16
13-34
26-99
99
99
99
99
0-281
45-0
16-6
16-26
13-63
26-965
99
1-635*
99
99
0-277
Mean
0-285
Crystallized Sulphate of Manganese, Mn S04-J-5 H2 O. Crystals of the salt isomor-
phons with blue vitriol.
speriments with Naphtha A.
Glass
2. Temperature of the Air 14'
3-l-14°-2.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
o
o
o
grms.
grms.
grm.
grm.
48-5
16-7
16-42
13-23
26-945
4-12
1-97
0-431
0-487
0-332
45-7
16-4
16-14
13-24
26-945
99
99
99
0-323
46-5
16-7
16-43
13-53
26-98
99
99
0-313
44-0
16-8
16-53
13-85
26-945
99
1-955*
99
??
0-322
Mean
0-323
Crystallized Sulphate of Nickel, Ni S04-{-6 H2 0. Crystals of quadratic nickel
vitriol dried in vacuo.
xperiments with Naphtha A.
Glass
1. Temperature of the Air 15
°-6-16°-
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
O
o
o
grms.
grms.
grm.
grm.
52-5
18-0
17-74
14-61
26-97
3-60
1-655
0-431
0-651
0-307
50-3
17-7
17-42
14-37
26-995
99
99
5)
0-322
51-5
17-7
17-36
14-24
26-985
99
„
0-313
52-8
181
17-82
14-62
26-94
9*
1-63*
5?
,,
0-314
Mean
0-313
After drying the stopper.
156
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
74. Crystallized Sulphate of Magnesia, Mg S04+7 H2 G. Air-dried crystals of Epsom
salt. I have made two series of experiments with this salt. In one the temperature
did not exceed 40°, and in the other did not attain 50°. In both cases the crystals
remained transparent and unchanged.
I. — Experiments with Naphtha A. Glass 3. Temperature of the Air 19°-8-19° -9.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
O
0
o
grms.
grms.
grm.
grm.
38-5
21 6
21-29
19-77
26-96
3-175
1-845
0-431
0-453
0-371
39-3
21-6
21-32
19-73
26-945
,,
55
55
5J
0-369
38*7
21-6
21-34
19-83
26-98
55
55
55
0-357
37-7
21-6
21-27
19-85
26-935
„
1-835*
55
„
0-356
Mean . . . O’ 363
II. — Experiments with Naphtha A. Glass 1. Temperature of the Air 16°T.
T.
T'.
tr.
t.
M.
m.
/•
y-
X.
sp. H.
o*
o
o
0
grms.
grms.
grm.
grm.
47-6
18-3
18-04
15-42
26-97
2-775
1-81
0-431
0-651
0-353
47*9
18-4
18-12
15-43
26-985
55
55
55
55
0-371
45-2
18-3
17-96
15-53
26-94
„
55
55
55
0-361
43-9
18-3
17-96
15-67
26-975
55
1-795
*
55
55
0-356
Mean . . . 0-360
These determinations give as the mean of the two series 0-362 for the specific heat of
crystallized sulphate of magnesia below 50°f .
Crystallized Sulphate of Zinc, Zn S04+7 H2 0. Transparent crystals of white vitriol,
dried in the air. In the determinations a heat but little over 50° could be employed;
towards 50° the crystals undergo decomposition in the coal-tar naphtha J.
Experiments with Naphtha A. Glass 1. Temperature of the Air 13°-4.
T. T'. t'. t. M. m. /. y<. x. Sp. H.
ooo o grms. grms. grm- grm.
28-7 14-6 14-33 12-93 26-945 3-55 1-655 0-431 0-651 0*369
30-7 14-9 14-62 13-13 26-95 „ „ „ „ 0-332
This series of experiments had to be interrupted here. I subsequently made another set.
* After drying the stopper.
f Above 50° the salt with 7 at. water of crystallization undergoes decomposition. A series of experiments
in which the temperature exceeded 50° gave the following results.
Experiments with Naphtha A. Glass 3. Temperature of the Air 20°-3-21°-l.
T.
T'.
t'.
t.
M.
m.
f-
y-
X.
sp. H.
o
51-5
22-6.
22:32
1061
grms.
26-995
grms.
3-43
grm.
1-57
0-431
grm.
0-453
0-409
51-4
22-8
22-52
19-55
26-93
„
„
)}
0-475
51-0
23-0
22-71
19-73
26-945
„
„
„
0-507
500’
23-0
22-71
19-81
26-93
„
1-56*
„
99
0-515
The results are as if more and more water in the free state had been eliminated.. After the experiments the
crystals were swollen, and externally milk white, still containing a clear nucleus inside.
% In the following series of experiments, in which a heat of towards 50° was employed, the crystals of white
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
157
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°-4-15°-Q.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
Q
o
0
grms.
grms.
grm.
grm.
3,0-9
15-7
15-43
14* * * §03
26-93
3-49
1-645
0-431
0-651
0-321
32-3
16-0
15-65
14-13
26-96
55
55
55
55
0-331
30-8
15-8
15-52
14-03
26-95
55
„
„
55
0-377
32-8
16-1
15-83
14-23
26-97
.55
1-635*
55
55
0-352
In all these experiments the crystals employed remained clear. The mean of the six
experiments gives 0-347 as the specific heat of crystallized sulphate of zinc.
Crystallized Sulphate of Iron, Ee S04+7 H2 0. Dry crystals of green vitriol.
Experiments with Naphtha A. Glass 2. Temperature of the Air 16°T.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
0
o
o
grms.
grms.
grm.
grm.
47-9
18*6
18-32
15-56
26-93
3-47
1-91
0-431
0-487
0-354
47-5
18-6
18-25
15-55
26-925
„
„
„
„
0-347
46-0
18-5
18-21
15-64
26-955
55
55
55
55
0-348
44-6
18-4
18-13
15-73
26-96
„
1-895*
55
55
0-336
Mean . . . 0-346
Crystallized Sulphate of Cobalt, Co B04+7 H2 G. Crystals of the salt isomorphous
with green vitriol. In the following experiments the crystals remained transparentf .
Experiments with Naphtha A. Glass 2. Temperature of the Air 13°'4-13°-2.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
0
o
o
grms.
grms.
grm.
grm.
31-6
14-9
14-63
12-96
26-97
3-445
1-895
0-431
0-487
0-405
29-9
14-8
14-54
13-14
26-945
55
55
55
,,
0-347
28-4
15-0
14-67
13-43
26-93
55
55
55
55
0-345
31-6
15-2
14-94
13-44
26-94
1-885*
55
0-338
Mean . . . 0-343 J
vitriol undergo an essential change. At the end of the experiments they were opaque, and no longer detached,
as before, hut as if swollen up in the glass. These experiments gave the following numbers : — ,
Experiments with Naphtha A. Glass 1. Temperature of the Air 14°-8-14°-4.
T.
T'.
t'.
t.
M.
TO.
/•
y-
X .
sp. H.
o
O
0
0
grms.
grms.
grm.
grm.
47-4
17-0
16-74
13-62
26-94
3-465
1-695
0-431
0*651
0-399
47-6
17-0
16-72
13-62
26-945
„
„
„
0-389
45-1
16-9
16-63
13-77
26-975
„
1-655 §
„
0-396
43-8
17-1
16-83
14-22
26-99
„
,,
„
0-368
* After drying the stopper.
f In a series of experiments, in which the temperature amounted to 50°, the crystals of sulphate of cobalt
with seven atoms of water underwent a change ; they were opaque, and stuck in the glass as if swollen up ;
and the numbers found for the specific heat were considerably greater.
J Excluding the first experiment. The temperature of the glass, together with the solid substance and the
liquid, exceeded in all experiments the final temperature of the water in the calorimeter only by about 15°.
§ After removing some naphtha from the stopper.
158
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
75. Crystallized Sulphate of Magnesia and Potass , Mg K2 S2 Os+ 6 H2 O. Well-
shaped crystals.
Experiments with Naphtha A. Glass 3. Temperature of the Air 17°’0-17°-2.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
51-0
19-4
19-13
16-43
grms.
26-99
grms.
4-135
grms.
1-735
0-431
grm.
0-453
0-267
51-0
19-3
19-02
16-33
26-965
5 5
55
55
55
0-263
50-0
19-3
19-02
16-43
26-96
55
55
55
55
0-260
50-2
19-4
19-06
16-44
26-95
55
1-715*
55
55
0-266
Mean . . . 0-264
Crystallized Sulphate of Zinc and Potass , -Zn K2S2G8-(-6H20. W ell-shaped crystals ;
in both the following series they remained transparent and unchanged.
1. — Experiments with Naphtha A. Glass 1. Temperature of the Air 19°-8-19°-9.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
40-2
21-7
21-37
19-73
grms.
26-925
grms.
3-965
grm.
1-535
0-431
grm.
0-651
0-271
40-6
21-7
21-42
19-75
26-935
3,
55
55
55
0-269
40-2
21-7
21-38
19-73
26-955
55
55
55
55
0-275
39-8
21-7
21-40
19-83
26-925
55
1-52*
55
55
0-260
Mean
0-269
II. — Experiments with Naphtha A. Glass 2.
Temperature of the Air 14°-8-140,4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
48-9
16-9
16-64
13-63
grms.
26-94
grms.
4-365
grm.
1-98
0-431
grm.
0-487
0-273
47-2
16-8
16-50
13-63
26-92
55
55
55
0-275
48-0
16-9
16-61
13-69
26-98
55
55
„
0-273
45-7
16-9
16-63
13-96
26-97
„
1*965 ’
55
55
0-267
Mean
0-272
The mean of the means of both series of experiments gives 0-270 as the specific heat
of crystallized sulphate of zinc and potass between 19° and 40°-50°.
Crystallized Sulphate of Nickel and Potass , Ni K2 S2 08+6 H2 O. Well-formed
crystals.
Experiments with Naphtha A. Glass 2. Temperature of the Air 130,3-13°-5.
T.
T'.
t'.
t.
M.
m.
/•
2/*
X.
sp. H.
49-1
o
16-1
15-84
12-77
grms.
26-94
grms.
4-775
grm.
1-945
0-431
grm.
0-487
0-247
45-1
15-6
15-34
12-61
26-96
55
„
55
>»
0-245
45-5
15-8
15-46
12-73
26-945
55
55
55
„
0-241
44-0
15-6
15-32
12-69
26-975
55
1-925*
55
jj
0-247
Mean . . . 0*245
* After drying the stopper.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
159
76. Crystallized Sulphate of Alumina and Potass , Al2 K2 S4 Gl6+24 H2 G. Transparent
air-dried crystals of alum.
Experiments with Naphtha A. Glass 1. Temperature of the Air 17°*2-17°*4.
T.
T'.
t'.
t.
M.
m.
/•
y-
07.
sp. H.
49*1
19*5
19*16
16*55
grms.
26*98
grms.
2*87
grm.
1*595
0*431
grm.
0*651
0*362
49*6
19*1
18*83
16*12
26*985
„
55
59
55
0*369
49*0
19*3
18*96
16*32
26*99
95
55
55
0*370
49*5
19*3
18*95
16*23
26*96
55
1*58*
„
55
0*382
Mean . . . 0*371
Crystallized Sulphate of Chrome and Potass , Or2 K2 S4 Gl6+24 H2 G. Air-dried
crystals of chrome alum : they remained unchanged in the following experiments.
Experiments with Naphtha A.
Glass 3.
Temperature of the
Air 17°
*2-17°*4.
T.
T'
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
O
o
o
grms.
grms.
grm.
grm.
50*9
19*3
19*03
16*14
26*95
3‘70
1*875
0*431
0*453
0*325
50*6
19*4
19*06
16*23
26*965
55
55
55
55
0*320'
50*9
19*5
19*23
16*34
26*995
*5
55
59
95
0*331
51*4
19*6
19*34
16*46
26*97
55
1*865*
55
55
0*320
Mean . . . 0*324
77. Chloride of Carbon , G2 Cl6. The determination of the specific heat of this, the
so-called sesquichloride of carbon, has given me much trouble.
I first investigated, in two series of experiments, a preparation which, after melting
in a small glass tube, had solidified in porcelain-like white crusts f.
I. — Experiments with Water. Glass 1. Temperature of the Air 18°*5-18°*8.
T.
T'.
t'.
t.
M.
m.
/•
y-
07.
sp. H.
53*5
20*5
20*22
16*16
grms.
26*94
grms.
3*765
grm.
1*61
1*000
grm.
0*651
0*280
52*2
20*4
20*10
16*18
26*945
55
55
55
„
0*282
52*0
20*7
20*43
16*83
26*97
55
59
55
55
0*269
52*6
20*8
20*45
16*61
26*965
55
1*585*
0*271
Mean . . . 0*276
* After drying the stopper.
t Sesquichloride of carhon was prepared by continuously passing chlorine into crude chloride of ethylene in
the sunlight, and washing the solidified product with water ; it was then again treated with chlorine and washed
with solution of soda and much water. The crystalline mass was afterwards repeatedly pressed between bibu-
lous paper (by which a small quantity of an oily product was absorbed), dried in the air, then washed with
cold alcohol, dried, and fused, and the parts which had crept up the sides separated when solid. — Eegelbacu.
MDCCCLXV.
Z
160
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
II. — Experiments with Water. Glass 1. Temperature of the Air 170,5-17°‘4.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
O
0
o
grms.
grms.
grm.
grm.
50-2
19-8
19-54
15-54
26-955
3-525
1-995
1-000
0-651
0-256
50-1
19-6
19-33
15-31
26-94
55
55
55
jj
0-257
50-5
19-7
19-36
15-24
26-96
V
55
55
„
0-272
49-2
19-7
19-43
15-52
26-97
„
55
55
w
0-263
47-8
19-7
19-36
15-62
26-99
5,5,
1-965*
55
„
0-277
Mean . . . 0-265
I should not have hesitated to take the number 0-27, the mean of the averages of both
these series of determinations, as the normal specific heat of sesquichloride of carbon, and
to consider it as sufficiently below the melting-point (according to Faraday this is at
160°), if the connexion between the specific heat of solid bodies and their composition,
discussed in § 96 et seq., had not been known to me; but the specific heat of sesqui-
chloride of carbon calculated therefrom is 0-177. This deviates from the number found
in a manner which at first I could not understand. The idea that the specimen was im-
pure was inadmissible f. To try whether the porcelain-like mass of sesquichloride which
solidified on fusion had an essentially different specific heat from that not fused, I re-
crystallized the substance from ether, washed the crystals (which showed very distinctly
the characteristic form of the body as described by Brooke and Laurent) with a little
ether, and dried them at 100°. Dried at this temperature, without being melted, they
were white, like porcelain, and gave now the following results.
III.— Experiments with Water. Glass 3. Temperature of the Air 18°*4-18°-7.
T.
T'.
t'.
t.
M.
m.
/
y •
X.
sp. H.
49-2
20-6
20-34
16-53
grms.
26-935
grms.
3-835
grms.
2-06
1-000
grm.
0-453
0-280
49-2
20-7
20-42
16-62
26-94
55
55
55
55
0-281
49-0
20*8
20-53
16-81
26-95
2-05*
55
5 5-
0-274
Mean . . . 0-275
That is essentially the same specific heat as my earlier experiments gave. If now it
was improbable that the specific heat of sesquichloride of carbon did not differ much
from 0-27, I might, on the other hand, also consider it improbable that this compound
would make an exception to the relation which I had found between specific heat
and composition — a relation which holds good in hundreds of cases of solid bodies.
Sesquichloride of carbon would be the only exception to the validity of this relation ;
but this single exception would be sufficient to disprove its universal applicability,
* After drying tlie stopper.
t In the specimen I investigated, Mr. Dehx found 90T9 per cent, chlorine ; the quantity calculated from
the formula C2 Cla is 89-88 per cent.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
161
and to leave it undecided when, and in how many cases, other such exceptions might
occur.
Although the great distance of the temperatures used in my experiments from the
melting-point of sesquichloride of carbon made it improbable, it was yet possible that
the specific heat of this body varies considerably at the temperatures which I used, and
is only constant and normal at still lower temperatures. In the preceding experiments I
had heated sesquichloride of carbon to 49°-52° ; it was improbable that this body, at so
great a distance from its melting-point (160°), should absorb latent heat in softening
in appreciable quantity, yet the circumstance that this substance is brittle in the
cold, but distinctly tougher at 50°, led me to determine the specific heat at lower tem-
peratures than in the previous case. I made the two following series of experiments, a
with sesquichloride crystallized from alcoholic, and b from ethereal solution : in both
series the crystals dried at 100° were porcelain white in appearance.
a.— Experiments with Water. Glass 1. Temperature of the Air 170,8.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H,
O
o
o
Q
grms.
grms.
grms.
grm.
36-8
19-7
19-35
17-42
26-98
2-11
2-085
1-000
0-651
0-146
37-6
19-8
19-52
17 52
26-94
55
„
55
„
0-138
37-2
19-7
19-44
17-51
26-94
55
55
55
55
0-111
37 T
19*8
19-45
17-53
26-98
55
2-075
55
0-127
b.—
Experiments with Water. Glass 3.
Temperature of
the Air
17°-8.
T.
T'.
t\
t.
M.
m.
/•
y-
X .
sp. H.
o
o
0
0
grms.
grms.
grms.
grm.
37*2
19-8
19-45
17-42
26-98
3-64
2-11
1-000
0-453
0-161
37-2
19*7
19-43
17-42
26-99
55
55
„
„
0-148
37-3
19-7
19-44
17-42
26-965
55
55
0-146
37-3
19-7
19-44
17-43
26-965
55
2-10
55
55
0-145
h these series
can only be considered
as giving approximate :
results.
In both the
magnitude T — T' is very small, not as much as 18°; in the series a the quantity of
solid was moreover small, and its thermal action but a small fraction of the entire
amount observed. The mean of the four experiments of the series b would give the
specific heat between 20° and 37° at 0T5, and the first experiment of the series a agrees
well with this. The specific heat here found between 20° and 37° comes very near that
calculated from the composition, and is so much less than that found between 20° and
50°, that it is probable this substance may towards 50° absorb heat in softening, the
amount of which may make the numbers for the specific heat too great.
To decide upon this point, T made two additional series of experiments in which, since
the vessel containing sesquichloride of carbon and water could only be slightly heated
* After drying the stopper.
z 2
162
PKOFESSOE KOPP ON THE SPECIFIC HEAT OE SOLID BODIES.
(not to 40°), and the difference of temperature T — T' accordingly was small, I used all
possible care. I thus obtained the following results.
a. Crystals obtained from ethereal solution dried at 100°: milky white.
Experiments with Water.
Glass 1.
Temperature of the Air 16°T-
-15°-7.
T.
T'.
t'.
t.
M.
m. /.
y • tf-
sp. H.
37 T
o
18-1
17-84
15-64
grins.
26-94
grms. grin.
3-58 1-845
grm.
1-000 0-651
0-174
37-1
18-2
17-92
15-73
26-99
55 55
55 55
0-176
37-2
18-0
17-72
15-63
26-985
„ 1-835*
„ „
0165
Temperature of the Air 16°T.
43-7
18-2
17-93
14-93
26-995
3-58 1-835
1-000 0-651
0-193
43-5
18-2
17-93
14-95
26-97
55 55
V 55
0-193
Temperature of the Air 16°-2.
51-9
18-4
18-12
13-86
26-995
3-58 1-82
1-000 0-651
0-269
48-6
18-1
17-77
13-84
26-975
55 55
55 55
0-281
Clear
crystals obtained from
ethereal
solution, dried by passing a current <
air over them at the ordinary temperature.
Experiments with Water.
Glass 3.
Temperature of the Air 16°-2-
-15°*7.
T.
T'.
t'.
. t.
M.
m. /.
y-
X.
sp. H.
36-9
18-2
17-93
15-62
grms.
26-99
grms. grms.
4-235 2-155
1-000
grm.
0-453
0-171
36-8
18-2
17-92
15-64
26-99
55 55
„
„
0-184
37-1
18-3
18-01
15-63
26-975
„ 2T45*
55
-
0-193
Temperature of the Air 16T°'-16C
>•2.
T.
T'.
t'.
t.
M.
m. /.
y-
X.
sp. H.
43-4
o
18-1
17-84
14-63
grms.
26-99
grms. grms.
4-235 2-145
1-000
grm.
0-453
0-195
43-4
18-2
17-90
14-70
26-96
55 55
55
55
0-195
Temperature of the Air 16°-2.
52-0
18-9
18-63
14-05
26-955
4-235 2T25
1-000
0-453
0-272
47-3
18-1
17-83
13-73
26-945
55 55
55
„
0-285
In the last series of experiments, on heating to about 50° a change took place in the
hitherto clear crystals ; they became dull and resembled porcelain. By special experi-
ments I found that transparent crystals of sesquichloride of carbon gradually heated in
water underwent this change at 50°-52°.
These determinations leave no doubt that, as is the case with other substancesf, for
* After drying the stopper.
f I call to mind the experiments of Pebsox, who found (Ann. de Chim. et de Phys. [3] vol. xxvii. p. 263)
for the specific heat of bees’ wax melting at 610,8,
Between —21° and +3° 6° and 26° 26° and 42° 42° and 58°
0-4287 0-504 0-82 1-72
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
163
temperatures near their melting-points, so also with sesquichloride of carbon at a
temperature of 50° (that is more than 100° from its melting-point), the specific heat
(or rather the number which is obtained for this in determinations) rapidly and con-
siderably increases. From the last two series of experiments the specific heat of sesqui-
chloride of carbon is
Between
18° and 37°.
Mean of experiments: a . . . 0172
' „ b . . . 0-183
Between
18° and 43°.
0193
0195
0-194
Between
18° and 50°.
0-275
0-279
0-277
Average 0*178
The specific heat of sesquichloride of carbon increases much more between 43° and
50° than between 37° and 43°. It may be assumed that for temperatures below 37° the
number found, 0-178, comes very near the true specific heat of this compound, that is,
uninfluenced by heat of softening.
78. Cane-sugar , G12H220u. Dried crystalline fragments of clear sugarcandy.
Experiments with Naphtha A. Glass 3. Temperature of the Air 20o,6.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
O
o
o
grms.
grms.
grm.
grm.
49-9
22-2
21-93
19-75
26-96
3-165
1-625
0-431
0-453
0-306
51-4
22-6
22-26
20-03
26-94
55
95
95
„
0-295
51-4
22-6
22-30
20-05
26-965
55
1-62*
95
55
0-302
Mean . . . 0-301
Fine loaf-sugar was recrystallized from water, the mother-liquor washed off with
dilute alcohol, the pure white crystals dried at 100°. They gave the following results.
Experiments with Naphtha B. Glass 1. Temperature of the Air 18°'5-18°*7.
T
T'.
t'.
t.
M.
m.
/•
y-
X,
sp. H.
O
O
0
o
grms.
grms.
grm.
grm.
51-5
20-9
20-62
18-16
26-945
2-915
1-54
0-419
0-651
0-299
51-6
20-7
20-43
17-95
26-95
„
59
55
„
0-297
50-3
20-6
20-33
17-94
26-985
55
1-52*
„
59
0-303
Mean . . . 0-300
I also examined amorphous cane-sugar. Crystals dried at 100°, as used in the pre-
ceding experiment, were melted in an oil-bath at 160°-170°, and the fused mass allowed
to cool in the closed tube. The resultant amorphous amber-like viscous mass, exactly
resembling colophony, was comminuted (as rapidly as possible to avoid the absorption
of moisture), and gave the following results.
After drying tlie stopper.
164
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Experiments with Naphtha B. Glass 1. Temperature of the Air 18o,0-18°-4.
T.
T'.
t'.
t.
M.
m.
/•
y-
x.
sp. H.
O
o
o
0
grms.
grms.
grm.
grm.
51-4
20-1
19-82
17-24
26-97
2-475
1-77
0-419
0-651
0-336
50-9
20-0
19-74
17-20
26-99
55
55
55
55
0-334
51-6
20-1
19-78
17-15
26-975
55
55
55
0-345
50-9
20-1
19-77
17-20
26-96
55
1-75*
55
55
0-357
Mean . . . 0-342
The pieces of amorphous sugar used for these experiments were clear even when the
experiments were concluded. In the investigation of such a hygroscopic substance it is
impossible to avoid with certainty any absorption of water ; yet it seems to me improbable
that the difference between the number O' 342 found for amorphous cane-sugar between
20° and 51°, and 0'301 for crystallized sugar between the same limits, depends on an
absorption of water by the former ; but it is probable that the greater specific heat
found for amorphous sugar depends on the fact that at 50° even it contains some heat
of softening. According to Wohler’s observations, bodies in the amorphous condi-
tion have other, in general lower, fusing-points than those in the crystallized statef;
crystallized cane-sugar melts at 160° C., amorphous between 90° and 100p; at the latter
temperature the amorphous sugar may be drawn out in threads, but even at a lower tem-
perature the softening begins.
Mannite , €6H14G6. Crystallized mannite, dried at 100°, was melted in the oil-bath
at 160°-170°, and the radiant crystalline mass was comminuted. It gave the following
results J.
Experiments with Naphtha B. Glass 3. Temperature of the Air 17°T-17°'8.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
O
o
o
grms.
grms.
grm.
grm.
51-1
19-3
18-92
16-57
26-98
2-56
1-815
0-419
0-453
0-318
51-6
19^4
19-12
16-64
26-93
55
„
55
55
0-336
51-0
19-5
19-19
16-82
26-965
55
55
55
0-319
51-3
19-6
19-31
16-92
26-93
55
1-805
*
55
55
0-321
Mean
0-324
After dryin
g the
stopper.
t Ann.
der Chem. und Pharm. vol. xli. p. 155.
I also worked with mannite which was
crystallized i
in slender prisms and dried at 100°.
Experiments with Naphtha B. Glass
3. Temperature of the Air 17°-4.
T.
T'.
t.
M.
m
/-
y
X.
sp. H.
O
O
0
0
grms.
grms.
grms.
gras.
49-5
19-2
18-85
16-61
26-95
2-13
2-14
0-419
0-453
0-302
51-3
19-3
19-03
16-64
26-94
„
„
0-311
50-5
19-3
19-04
16-74
26-98-
,,
2- 13*
99
0-302
I consider the somewhat larger numbers obtained by using the compact pieces which had been melted to be
more correct.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
165
79. Tartaric Acid , 04 Hfl Ofi. Dried fragments of larger crystals.
Experiments with Naphtha A. Glass 1. Temperature of the Air 20°-6.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
Q
0
o
0
grins.
grms.
grm.
grm.
51-3
22-4
22-12
19-74
26-985
3-16
1-53
0-431
0-651
0-289
50-5
22-5
22-23
19-94
26-96
99
„
„
0-283
50-7
22-6
22-32
20-03
26-97
99
1-52*
yy
it
0-282
Mean . . . 0-285
Small crystals dried at 100°.
Experiments with Naphtha B. Glass 3. Temperature of the Air 18o,0-18°-4.
T.
6
T'.
o
t'.
o
t.
0
M.
grms.
m.
grms.
/•
grm.
y-
X.
grm.
sp. H.
51-1
20-0
19-68
17-15
26-97
3-57
1-69
0-419
0-453
0-289
50-9
20-0
19-72
17-20
26-99
99
99
99
99
0-291
51-3
20-0
19-73
17-18
26-97
99
„
99
„
0-290
50-5
19-9
19-63
17T3
26-97
99
1-68*
99
Mean
99.
0-293
0-291
The average of the means of both series of experiments gives 0-288 as the specific
heat of crystallized tartaric acid between 21° and 51°.
Crystallized Bacemic Acid , €4He06+H20. Fragments of air-dried transparent
crystals, which remained clear in the experiments made with them.
Experiments with Naphtha B. Glass 1. Temperature of the Air 16°'4-16°-9.
T.
T',
t'.
t.
M.
m.
/•
y-
X .
sp. H.
o
o
0
o
grms.
grms.
grm.
grm.
50-5
18-6
18-33
15-63
26-945
3-17
1-495
0-419
0-651
0-317
50-3
18-6
18-33
15-64
26-965
tt
99
99
99
0-319
50-6
18-7
18-43
15-73
26-965
„
99
99
99
0-317
50-0
18-8
18-52
15-86
26-975
„
1-48*
„
99
0-324
Mean
0-319
Succinic
Acid, €4H604.
Small
crystals dried at 100°.
Experiments with Naphtha B.
Glass 1.
Temperature of the Air 17°
•3-17°-:
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
o
O
0
0
grms.
grms.
grm.
grm.
51-4
19-4
19-05
16-54
26-985
2-455
1-64
0-419
0-651
0-317
50-5
19-4
19-13
16-70
26-95
99
99
99
0-313
50-8
19-5
19-24
16-80
26-965
99
99
0-311
50-9-
19-6
19-26
16-82
26-935
99
1-625
99
0-313
Mean . . 0-313
After drying the stopper.
166
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
80. Formiate of Baryta, G2 H2 Ba 04. Beautiful clear crystals dried at 100°.
Experiments with Naphtha B. Glass 3. Temperature of the Air 180*5-18°*8.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
o
or- 1
20*6
20*31
17*93
grms.
26*98
grms.
6*91
grm.
1*615
0*419
grm.
0*453
0*142
53*1
20*7
20*40
17*85
26*94
55
55
„
„
0*143
51*8
20*7
20*41
17*95
26*97
55
55
55
55
0*145
52*4
20*7
20*38
17*93
26*99
55
1*58*
55
55
0*141
Mean . . . 0T43
Crystallized Neutral Oxalate of Potass, C2 K2 04+H2 O. Air-dried transparent crystals,
which remained clear in the experiments made with them.
T.
T'.
t'.
t.
M.
m.
/■
y-
X.
sp. H.
O
0
0
0
grms.
grms.
grm.
grm.
49*4
19*3
19*00
16*52
26*995
3*57
1*765
0*419
0*651
0*233
49*3
19*4
19*12
16*62
26*95
„
55
55
55
0*241
49*0
19*5
19*15
16*72
26*945
„
55
55
55
0*232
50*0
19*6
19*26
16*73
26*97
„
1*755*
„
55
0*240
Mean . . . 0*236
Crystallized Oxalate of Potass (quadroxalate), C2 H K 04+C2 H2 04 + 2 H2 O. Crystals
dried in the air, which were also clear after the experiments.
Experiments with Naphtha B. Glass 3. Temperature of the Air 16°‘7-16°*9.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
0
0
o
0
grms.
grms.
grm.
grm.
50*1
18*6
18*34
15*77
26*965
3*375
1*76
0*419
0*453
0*283
49*8
18*7
18*42
15*86
26*98
„
„
55
55
0*288
50*2
18*8
18*45
15*91
26*98
55
„
55
55
0*278
50*3
18*7
18*43
15*86
26*95
55
1*745
*
55
„
0*282
Mean . . . 0*283
Acid Tartrate of Potass, G4H5K06. Crystals dried at 100°.
Experiments with Naphtha B. Glass 3. Temperature of the Air 16°*6-16°*8.
T.
T'.
t'.
t.
M.
m.
/•
y-
X .
sp. H.
O
o
0
o
grms.
grms.
grm.
grm.
50*8
18*6
18*32
15*73
26*965
3*89
1*69
0*419
0-453
0*259
51*0
18*6
18*34
15*72
26*95
55
55
55
55
0*262
50*6
18*7
18*41
15*85
26*935
55
55
55
55
0*257
50*3
18*6
18*34
15*84
26*965
55
1*675
*
55
55
0*250
Mean . . . 0*257
After drying the stopper.
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
167
Crystallized Tartrate of Soda and Potass , G4 H4 Na K 06 + 4 Ha 0. Fragments of
transparent air-dried Seignette salt, which remained clear in the experiments made
with them.
Experiments with Naphtha B. Glass 1. Temperature of the Air 16°‘7-16°‘9.
T.
T'.
t'.
t.
M.
m.
/•
y-
X.
sp. H.
O
O
Ot
o
grins.
grms.
grm.
grm.
50-0
19-0
18-72
16-03
26-99
3-385
1-415
0-419
0*651
0-324
50-5
18-8
18-47
15-68
26-93
„
yy
yy
0-333
50-5
18-9
18-57
15-82
26-95
yy
yy «
yy
yy
0-325
50-4
18-9
18-61
15-84
26-965
yy
yy
yy
0-333
50-5
18-9
18-57
15-83
26-965
yy
1-40*
yy.
yy
0-325
Mean . . . 0-328
Crystallized Acid Malate of Lime, €4 H4 Ca 0a-f 04 H6 05 + 8 H2 O. Small crystals
dried over sulphuric acid, which remained clear in the following experiments :
T.
o
T'.
o
t'.
o
t.
o
M.
grms.
m.
grms.
f.
grm.
y-
X.
grm.
sp. H.
50-8
19-4
19-11
16-55
26-985
2-76
1-89
0*419
0-453
0-346
50-1
19-5
19-20
16-73
26-965
yy
yy
yy
„
0-337
50-5
19-6
19-34
16-84
26-94
yy
yy
„
0-339
50-4
19-6
19-27
16-82
26-97
yy
1-865* „
Mean
5)
0-330
0-338
IY.— TABLE OF THE SUBSTANCES WHOSE SPECIFIC HEAT HAS BEEN
EXPEEIMENTALLY DETEEMINED.
81. In the following I give a summary of those solid substances of known composition
for which there are trustworthy determinations of the specific heat. I have endea-
voured to make this summary complete ; yet I have not thought it necessary to include all
known determinations; for instance, all those referring to the metals most frequently
investigated. But it appeared to me desirable to include completely the determinations
of experimenters who have investigated a greater number of substances, in order to see
how far the results obtained by different inquirers are comparable ; in inserting the
numbers which I found for many substances of which the specific heats had been
already determined by others, I had no other intention than that of offering criteria for
judging how far these determinations are comparable, and1 may be used for the con-
siderations which are given in the fifth Division.
The determinations given in the following summary are principally due to Dulong
and Petit (D. P.), Neumann (N.), Regnault (R.), and myself (Kp.). There are besides
some of Person (Pr.), of Alluard (A.), and the recent investigations of Pape (Pp.) are
also included. By far the largest number of these detemiinations have been made by
the method of mixture. A few only of the elements investigated by Dulong and Petit,
mdccclxv.
After drying the stopper.
2 A
168
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
and some of the chemical compounds by Neumann have been determined by the method
of cooling. Where it is not otherwise stated in reference to the temperature, all deter-
minations refer to temperatures between 0° and 100°. Where the determination has
been made beyond these limits, or where a more accurate statement of temperature is
important, it is noticed. Where the same substance has been repeatedly investigated
by the same observer, the result obtained for the purer preparation, and in general the
most certain result, is taken.
In the following the chemical formula is given for each substance, the symbols
used both here and subsequently, when not otherwise mentioned, refer to the numbers
given in the last column of § 2 as the most recent assumptions for the atomic weights,
the corresponding atomic weight, and the atomic heat, viz. the product of the specific
heat and the
atomic weight.
82. Elements and Alloys.
Atomic
Specific
weight.
heat.
0-0557
Ag . . .
00
o
rH
0-0570
0-0560
A-l . . . .
. . 27 4 |
0-2143
0-202
As . . .
. . 75
0-0814
Au . . .
. . 197
''Amorphous . .
0-0298
0-0324
0-254
B . . . .
. . 10-9 '
) Graphitoidal
0-235
| Crystalline ....
0-225-
0-230
-0-262
(
1
0-0288
Bi . . . .
. . 210 <
| * * ‘ ‘ ’ ’ ’
0-0308
0-0305
Br . .
. . 80
Between —78° and 20°
0-0843
'’Wood charcoal .
0-241
Gas carbon ....
99 ....
0-204
0-185
C . . . .
. . 12 -
Natural graphite
99 •
0-202
0-174
Iron graphite . . .
0-197
99 ...
0-166
^Diamond
0-1469
€d . . .
. . 112 <
f
0-0567
0-0542
Go' . . .
. . . 58-8
|
r
0-1067
0-0949
Gu
. . 63*4 -
) Hammered ....
0-0935
1 Heated
f
0-0952
0-0930
0-1100
I
¥e
. . . 56 •
::::::::
0-1138
0-112
Hg . .
. . 200 .
Between —78° and —40°
0-0319
Atomic
heat.
D. P.
6-02
R.
6-16
Kp.
6-05
R.
5-87
Kp.
5-53
R.
6-11
D. P.
5-88
R.
6-38
Kp.
2-77
R.
2-56
Kp.
2-51
R. 2-45
-2-86
D. P.
6-05
R.
6-47
Kp.
6-41
R.
6-74
R.
2-89
R.
2-45
Kp.
2-22
R.
2-42
Kp.
2-09
R.
2-36
Kp.
1-99
R.
1-76
R.
6-35
Kp.
6-07
R.
6-27
1). P.
6-02
R.
5-93
R.
6-04
Kp.
5-90
D.P.
6-16
R.
6-37
Kp.
6-27
R.
6-38
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
169
Sb
Se .
Si .
Sn
Te
T1
W
Zn
Atomic
Specific
Atomic
weight.
heat.
heat.
I .
127
0-0541
R.
6-87
ir
..... 198
0-0326
R.
6-45
K .
39-1
Between
— 78° and % . . .
0-1655
R.
6-47
Li .
7
0-9408
R.
6-59
Mg
24
• • •
0-2499
R.
6-00
0-245
Kp.
5-88
Mn
55 .
0-1217
R.
6-69
Mo
96 .
0-0722
R.
6-93
Na
23 .
Between
-34° and 7°. . .
0-2934
R.
6-75
M
58-8
0-1092
R.
6-42
Gs
199-2
0-0311
R.
6-20
'"Yellow, between 13° and 36°
0-202
Kp.
6-26
55
„ 7° „ 30°
0-1895
R.
5-87
P .
31 <
55
„ ~21° „ 7°
0-1788
Pr.
5-54
55
„ -78° „ 10°
0-1740
R.
5-39
LRed
„ 15° „ 98°
0-1698
R.
5-26
r . . .
0-0293
D.P.
6-06.
Pb
to
o
—7
)
0-0314
R.
6-50
i . . .
0-0315
Kp.
6-52
Pd
106-6 .
0-0593
R.
6-32
I
r
0-0314
D.P.
6-20
Pt
197-4 -
\
0-0324
R.
6-40
1
)
0-0325
Kp.
6-42
R-h
104-4
0-0580
R.
6-06
1
0-1880
D. P.
6-02
S .
32 -
Rhombic, between 14° and 99°
0-1776
R.
5-68
l
L 55
„ 17° „ 45°
0-163
Kp.
5-22
0-0507
D.P.
6-20
122
79-4
28
118
128
204
184
65-2
( Amorphous, bet. —27° and 8°
« Crystalline, „ 98° „ 20°
L » m » -18° „ 7°
f Grapbitoidal
Crystallized
4 „ .... 0-167-
Fused
0-156-
0*0508
0-0523
0-0746
0-0762
0-0745
0-181
0-165
-0-179
0-138
-0-175
0-0514
0-0562
0-0548
0-0474
0-0475
0-0336
0-0334
0-0927
0-0956
0-0932
It.
Kp.
R.
R.
R.
Kp.
Kp.
R.
6-20
6-38
5- 92
6- 05
5-92
5-07
4-62
4-68-5-01
Kp.
R. 4-
D. P.
R.
Kp.
R.
Kp.
R.
R.
D.P.
R.
Kp.
3-86
-4-90
6-06
6-63
6-46
6-07
6-08
6-85
6-15
6-04
6-23
6-08
2 a 2
170
PROEESSOR KOPP ON THE SPECIFIC HEAT OE SOLID BODIES.
Alloys which only melt far above 100°.
Atomic
•Specific
Atomic
weight.
heat.
heat.
Bi Bn ...
. 328
0-0400
R.
13,1
Bi Sn2 . . .
. 446
0-0450
R.
20-1
Bi Sn2Sb . .
. 568
0-0462
R.
26-2
BiSn2SbZn2 .
. 698-4
0-0566
R.
39-5
Pb Sb . . .
. 329
0-0388
R.
12-8
Pb Bn ...
. 325
0-0407
R.
13-2
PbSn2 . . .
. 443
83. Arsenides and Sulphides.
0-0451
R.
20-0
Co As2 . . .
. 208-8
Speis cobalt
0-0920
N.
19-2
As the locality of this mineral is not given, the formula and atomic weight are not
certain. Metals replacing the cobalt can, however, have little influence
on the
atomic
weight and
the
product.
Ag2S. .
. . 248
F used ....
0-0746
R.
18-5
€o As S .
. . 166
Cobalt glance
0-1070
N.
17-8
Cu2 B .
. . 158-8 <
Fused ....
Copper glance
0-1212
0-120
R.
Kp.
19-2
19-1
PeAsB .
. . 163
Mispickel . . .
0-1012
N.
16-5
AsS . .
. . 107
Commercial
01111
N.
11-9
CoS . .
. . 90-8
Fused ....
0-1251
R.
11-4
Cui Pei S
. . 91-7 1
Copper pyrites
0-1289
0-131
N.
Kp.
11-8
12-1
Be S . .
. . 88
Fused ....
0-1357
R.
11-9
' Cinnabar . .
0-052
N.
121
HgB . .
. . 232 \
55 •
0-0512
R.
11-9
(
0-0517
Kp.
12-0
M'S . .
. . 90-8
Fused ....
0-1281
R.
11-6
' Galena ....
0-053
N.
12-7
PbS . .
. . 239 ^
0-0509
R.
12-2
(
' „ ....
0-0490
Kp.
11-7
SnS . .
. . 150
Fused ....
0-0837
R.
12-6
I
r Zinc-blende
0-1145
N.
11-1
Zn S . .
. . 97-2 *
|
0-1230
R.
12-0
1
0-120
Kp.
11-7
Pe7S8 .
. . 648 <
\ Magnetic pyrites
0-1533
0-1602
N.
R.
99-3
103-8
As9 So
. . 246
Natural ....
0-1132
N.
27-8
Bi2 S3 .
. . 516
Artificial
0-0600
R,
31-0
Sb2S3 .
. . 340 <
f Natural . . .
0-0907
N.
30-8
1 Artificial
0-0840
R.
28-6
CMarcasite . . .
0-1332
N.
164)
] Iron pyrites
0-1275
N.
15-3
PeS2 . .
. . 120 ‘
0-1301
R.
15-6
l
0-126
Kp.
15-1
Mo S2 .
. . 160 i
\ Natural . . .
0-1067
0-1233
N.
R.
171
19-7
Bn S2 .
. . 182
Aurum musivum
0-1193
R.
21-7
PROFESSOK KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
84.
AgCl.
€u Cl .
Hg Cl.
KC1 .
Li Cl .
NaCl .
Rb Cl .
NH4C1
Ba Cl2
Ca Cl2
SgCl2
MgCl2
Mn Cl2
Rb Cl2
Bn CL
Sr Cl 2 .
Zn Cl2
BaCl2+2H20
CaCl2+6H“
Rt K2 Cl6
Bn K9 CL
Cr2Cl6
AgBr
KBr .
Na Br
Pb Br2
Agl
Cul
Hgl
KI
Nal
Hgl2
Rbl2
CaTL
A1 Na3 Fle
0
Atomic
weight.
143-5
98-9
235-5
74-6
42-5
58-5
120-9
53-5
Fused .
Sublimed
Fused .
Rock-salt
Fused .
208
111
271
j Fused
I » -
99
f Sublimed
95
126
278
189
158-6
136-2
244
219
285-4
488-6
409-2
317-4
188
119-1
103
367
235
190-4
327
166-1
150
454
461
78
210-4
( Fused
I ,,
Between —21° and 0°
Fused
Powder
Fused
Fluor-spar
DLID BODIES.
171
impounds.
Specific
heat.
0-0911
R.
Atomic
heat.
13-1
0-1383
R.
13-7
0-0521
R.
12-3
0-1730
R.
12-9
0-171
Kp.
12-8
0-2821
R.
12-0
0-2140
R.
12-5
0-213
Kp.
12-5
0-219
Kp.
12-8
0-112
Kp.
13-5
0-373
Kp.
20-0
0-0896
R.
18-6
0-0902
Kp.
18-8
0-1642
R.
18-2
0-0689
R.
18-7
0-0640
Kp.
17-3
0-1946
R.
18-5
0-191
Kp.
18-2
0-1425
R.
18-0
0-0664
R.
18-5
0-1016
R.
19-2
0-1199
R.
19-0
0-1362
R.
18-6
0-171
Kp.
41-7
0-345
Pr.
75-6
0-152
Kp.
43-4
0-113
Kp.
55-2
0-133
Kp.
54-4
0-143
Kp.
45-4
0-0739
R.
13-9
0-1132
R.
13-5
0-1384
R.
14-3
0-0533
R.
19-6
0-0616
R.
14-5
0-0687
R.
13-1
0-0395
R.
12-9
0-0819
R.
13-6
0-0868
R.
13-0
0-0420
R.
19-1
0-0427
R.
19-7
0-2082
N.
16-2
0-2149
R.
16-8
0-209
Kp.
16-3
0-238
Kp.
50-1
* The preparation contained carbonate of soda.
172
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Atomic
85. Oxides.
Specific
Atomic
weight.
heat.
heat.
Gu2 O . . .
. . 142-8 \
\ Bed copper ore
99
0-1073
0-111
N.
Kp.
15-3
15-9
H20 . . .
. . . 18 J
[ Ice between —21° and — 2° .
0-480
Pr.
8-6
1 „ 78° „ 0° .
0-474
B.
8-5
Desains found the specific heat of ice between —20° and 0° to be 0513 ; Person, be-
tween — 20° and 0° =0-504 ; Hess, between —14° and 0° =0-533. Person is of opinion
that ice, even somewhat below its melting-point, between —2° and 0°, absorbs heat of
fusion.
GuG . .
MgO . .
Mn G . . .
MO . . .
Pb O . . .
ZnO
Mg 0+H2G
Fe3 04
Mg Al2 04 .
Mg*Fe*Gr*Al*
A1203 . .
As2 Oq . .
b2 03
Bi203
0ro 0Q
O,
*eTi*Oa .
Sb2 03 . .
Mn2 03+H2G
79-4
216
40
71
74-8
223
Commercial
Crystalline
Feebly ignited
Strongly ignited .
Fused ....
Crystalline powder
81
58
232
-{
Brucite . .
Magnetic iron ore
142-8
196
102-8
198
69-8
468
152-4
160
■i
Spinelle
Chrome iron ore .
Sapphire
Opaque
Fused
. 155-5
. 292
. 176
Crystalline ....
Artificial, feebly ignited
„ strongly ignited
Specular iron ....
Iserine
Fused .
Manganite
0-137
N.
10-9
0-1420
B.
11-3
0-128
Kp.
10-2
0-049
N.
10-6
0-0518
B.
11-2
0-0530
Kp.
11-4
0-276
N.
11-0
0-2439
B.
9-8
0-1570
B.
11-1
0-1623
B.
12-1
0-1588
B.
11-9
0-0509
B.
11-4
0-0512
B.
11-4
0-0553
Kp.
12-3
0-132
N.
10-7
0-1248
B.
10-1
0-312
Kp.
18-1
0-1641
N.
38-1
0-1678
B.
38-9
0-156
Kp.
36-2
0-194
Kp.
27-7
0-159
Kp.
31-2
0-1972
N.
20-3
0-2173
B.
22-3
0-1279
B.
25-3
0-2374
B.
16-6
0-0605
B.
28-3
0-196
N.
29-9
0-1796
B.
27-4
0-177
Kp.
27-0
0-1757
B.
28-1
0-1681
B.
26-9
0-1692
N.
27-1
0-1670
B.
26-7
0-154
Kp.
25-1
0-1762
N.
27-4
0-177
Kp.
27-5
0-0901
B.
26-3
0-176
Kp.
31-0
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Pyrolusite
f Quartz
Mn G2 . .
Atomic
weight.
. . 87
SiG2 . . .
. . 60
SixZr*G2 .
. . 90*8
Sn 02
. . 150
TiG2 . . .
. . 82
-Mo G3 . . .
. . 144
wo3 . . .
. . 232
K2GG3 . .
. . 138*2
Na2GG3. .
. . 106
Rb2 G ©3 . .
. . 230*8
Ba G ©3
. . 197
€a€Qg
CaxMgi€G3
Fe G ©0
1
Zircon
Cassiterite
Artificial
Eutile .
Brookite
Fused .
| Pulverulent
86. Carbonates and Silicates.
Fused
Witherite
100
92
116
-Calc-!
spar
Arragonite
rr
| Spathic iron
SOLID BODIES.
173
Specific
Atomic
heat.
heat.
0*159
Kp.
13*8
0*1883
N.
11*3
0*1913
E.
11*5
0*186
Kp.
11*2
0*1456
E.
13*2
0*132
Kp.
12*0
0*0931
N.
14*0
0*0933
E.
14*0
0*0894
Kp.
13*4
0*1716
E.
14*1
0*1724
N.
14*1
0*1703
E.
14*0
0*157
Kp.
12*9
0*161
Kp.
13*2
0*1324
E.
19*1
0*154'?
Kp.
22*2
0*0798
R.
18*5
0*0894?
Kp.
20*7
0*2162
R.
29*9
0*206
Kp.
28*5
0*2728
E.
28*9
0*246
Kp.
26*1
0*123
Kp.
28*4
0*1078
N.
21*2
0*1104
R.
21*7
0*2046
N.
20*5
0*2086
R.
20*9
0*206
Kp.
20*6
0*2018
N.
20*2
0*2085
R.
20*9
0*203
Kp.
20*3
0*2161
N.
19*9
0*2179
R.
20*0
0*206
Kp.
19*0
0*182
N.
21*1
0*1934
R.
22*4
The minerals investigated doubtless contained part of the iron, replaced by metals of
lower atomic weight. The atomic weight and the product assumed above are somewhat
too great.
Feji. Mm?T Mg^ G G3 1 1 2 • 9
Mg-FejGOj, . . 91 T
PbG0Q . .
267
Spathic iron 0T66
( Cerussite
1
0*166
Kp.
18*7
0*227
N.
20*7
0*0814
N.
21*7
0*0791
Kp.
21*1
Eegnault found for precipitated carbonate of lead still containing water, the specific
heat 0*0860.
174
PKOFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Atomic
Specific
Atomic
•weight.
heat.
heat.
Sr € 03 . . .
. 147-6-
Strontianite
Artificial .
0-1445
0-1448
N.
R.
21-3
21-4
GaSi 03 . .
. 116
Wollastonite
0-178
Kp.
20-7
Gai Mgi Si 03 .
. 108 j
[ Diopside from Tyrol
[ . »
0-1906
0-186
N.
Kp.
20-6
20-1
CuSi 03-f H2 0
. 157-4
Dioptas
0-182
Kp.
28-7
|
f Olivine
0-189
Kp.
27-6
MgfrFeT?rSi 04
. 145-8^
Crysolite
0-189
Kp.
27-6-
1
0-2056
N.
30-0
1
| Adularia
0-1861
N.
103-7
Al2 K2 Si6 016 .
. 557 \
Orthoclase
0-1911
N.
106-4
1
1 „
0-183
Kp.
101-9
Al2 Na2Si6016 .
. 524-8 j
i Albite
0-1961
0-190
N.
Kp.
102-9
99-7
Borates , Molybdates , Tungstates , Chromates, and Sulphates.
KB02 . . . .
82'
Fused
. . 0-2048
R.
16-8
NaB02 . . . .
65-9
55 ••••••
. . 0-2571
R.
16-9
Bb B2 04 . . . .
292-8
55.
. . 0-0905
R.
26-5
Pb B4 07 . . . .
362-6
55
. . 0-1141
R.
41-4
K2B407 . . . .
233-8
55
. . 0-2198
R.
51-4
Na2B407 . . .
201-6 j
[ ::::::
. . 0-2382
. 0-229
R.
Kp.
48-0'
46-2
Na2B407 + lOH20
381-6
Crystallized borax
. . 0-385
Kp.
146-9
Pb Mo 04 . . .
367
Yellow lead ore . . .
. . 0-0827
KP.
30-4
GaW04 . . .
2:88
Scheelite
. . 0-0967
Kp.
27-9
Pe| Mnf W 04 . .
303-4 j
\ Tungsten
1 „
. . 0-0930
. . 0-0978
Kp.
R.
28-2
29-7
The locality of the wolfram investigated by Regnault is not known, and the com-
position uncertain. But the change in the ratio in which iron and manganese are
present in the mineral alters little in the atomic weight.
PbGr 04
K2 Gr ©4
K2Gr207
khso4
k2so4 .
Na2S04 .
n2h8so4
BaS04 .
Ca S©4
. 323.4
. 194-4
. 2:94-6
. 136-1
. 174-2
. 142
. 132
. 233
. 136
Fused
0-0900
Kp.
29-0
Crystallized
0-1851
R.
36-0
5?
0-189
Kp.
36-7
55
0-1894
R.
55-8
55
0-186
Kp.
54-8,
5? *
0-244
Kp.
33-2
Fused
0-1901
R.
33.-1
Crystallized
0-196
Kp.
34-1
Fused
0-2312
R.
32-8
Crystallized
0-227
Kp.
32-2
,5 .
0-350
Kp.
46-2
Heavy spar
0-1088
K
25-4
0-1128
R.
26-3
9?
0-108
Kp.
25-2
Calcined gypsum ....
0-1966
R.
26-7
Anhydrite .' .
0-1854
N.
25-2
55 •••••••
0-178
Kp.
24-2
PROFESSOR
KOPP
ON THE SPECIFIC HEAT
OF
SOLID BODIES.
175
Atomic
Specific
Atomic
weight.
heat.
heat.
€uSG4
159-4
Solid pieces
. 0-184
Pp.
29-3
MgS04
120 J
Dehydrated salt .
. 0-2216
R.
26-6
Solid pieces . .
. 0-225
Pp.
27-0
MnS04
151
,,
. 0-182
Pp.
27-5
Artificial .
. 0-0872
R.
26-4
PbS04 .....
303 4
Lead vitriol
. 0-0848
N.
25-7
l
. 0-0827
Kp.
25-1
Artificial .
. 0-1428
R.
26-2
SrS04
183-6 ^
Celestine . . .
. 0-1356
N.
24-9
i
. 0T35
Kp.
24-8
ZnS04
161-2
Coarse powder
. 0-174
Pp.
28-0
0uS04+HQ0 . .
177-4
Pulverulent
. 0-202
Pp.
35-8
Mg S04+H9 0 . .
138
Coarse powder
. 0-264
Pp.
36"4
ZnS04+Ho 0 . . .
179-2
Solid pieces
. 0-202
Pp.
36-2
€aS04+2H20 . .
172 j
Gypsum . . .
. 0-2728
. 0-259
N.
Kp.
46-9
44-6
€uS04+2H20 . .
195-4
Pulverulent
. 0-212
Pp.
41-4
ZnS04+2H20 . .
197-2
Solid pieces
. 0-224
Pp.
44-2
Fe S04+3 H20
206
99 *
. 0-247
Pp.
50-9
€uS04+5H20 . .
249-4 J
[ Crystallized . .
L
. 0-285
. 0-316
Kp.
Pp.
71-1
78-8
MnS04+5H20 . .
241 J
l :: : :
. 0-323
. 0-338
Kp.
Pp.
77-8
81-5
MS04+6 He, 0 . .
262-8
99 • *
. 0-313
Kp.
82-3
0oB04+7H;0 . .
280-8
99 * ■
. 0-343
Kp.
96-4
FeS04+7H20 . .
278 j
f
. 0-346
. 0-356
Kp.
Pp.
96-2
99-0
MgS04+7H20 . .
246 J
i ” : :
. „ 0-362
. 0-407
Kp.
Pp.
89-1
100-1
ZnS04+7H20 . .
287-2 -
1 : :
. 0-347
. 0-328
Kp.
Pp.
99-7
94-2
Mg K2 S2 08+ 6 H9 0
402-2
99
. 0-264
Kp.
106-2
NiK2 s2 08+61I20
437
99
. 0-245
Kp.
107-1
ZnK2 B.,08+6 HL0
443-4
99
. 0-270
Kp.
119-7
A12K2S4016+24H20
949
„ alum
. 0-371
Kp.
352-1
€r2K2S4016+24H20
998-6
„ chrome alum
. 0-324
Kp.
323-6
88. Arseniates, Phosphates, Pyrophosphates and Metaphosphates, Nitrates, Chlorates ,
Perchlorates, and Permanganates.
K As 03 . . . .
162-1
Fused '. . . . . .
. . 0-1563
R.
25-3
K H2 As 04 . . .
180-1
Crystallized ....
. . 0-175
Kp.
31-5
Pb3As208 . . . .
899
Fused
. . 0-0728
R.
65-4
Ag3P04 . . . .
419
Pulverulent ....
. . 0-0896?
Kp.
37-5
KH2P04 . . . .
136-1
Crystallized ....
. . 0-280
Kp.
28-3
Na2HP04+12H20
358
Between — 21° and 2° .
. . 0-408
Pr.
146-1
The determination of the specific heat refers to the crystallized salt. For the fused
and afterwards solidified salt Person found the specific heat between the same range of
temperature considerably greater, =0'68 to 0'78; but the mass obtained by solidifying
MDCCCLXV. 2 B
176
PROFESSOR ZOPP OA THE SPECIFIC HEAT OE SOLID BODIES.
the fused salt gradually alters
(it becomes crystallized again) with increase of volume,
which is very considerable when the fused salt is allowed to cool very rapidly.
Atomic
Specific
Atomic.
weight.
heat.
heat.
Pb3P2 08 . . . .
811
0-0798
R.
64.7
k4p907 . . . .
330-4
Fused
0-1910
R.
63-1
Na4 P2 07
266
0-2283
R.
60-7
Pb9 P9 07 . . . .
588
0-0821
R.
48-3
Na P 03
102
0-217
Kp.
22-1
CaP2©6 . . . .
198
0-1992
R.
39-4
Ag N 03 . . . .
170
0-1435
R.
24-4
[ „
0-2388
R.
24-1
KN03
101-14
,
0-227
Kp.
22-9
Ki Na4 N 03 . . .
Crystallized
0-232
Kp.
23-5
93
Fused*
0-235
Pr.
21-9
„
0-2782
R.
23-6
Na N 03 . . . . .
85
0-256
Kp.
21-8
N2H403 . . . .
1
[ Crystallized ......
0-257
Kp.
21-8
80
0-455
Kp.
36-4
Ba N2 06 . . . .
261 j
r
0T523
0-145
R.
Kp.
39*8
37-9
Pb N2 06
331
3i5
0-110
Kp.
36-4
Sr N2 06 . . . .
211-6
0-181
Kp.
38-3
K Cl 03 , . . . .
122-6 j
i Fused
Crystallized
5?
0*2096
0-194
R.
KP.
25*7
23*8
BaCl206+H20 . .
322
0-157
Kp.
50-6
K Cl 04 . . . . .
138-6
0-190
Kp.
26-3
K Mn 04 . . . .
158-1
5?
0*179
Kp.
28*3
89.
So-called Organic Compounds.
Hg€2N2 . . . .
252
Crystallized cyanide of mercury
0-100
Kp.
25*2
ZnK204N4 . . .
247-4 J
\ ,, cyanide of zinc and ]
1 potassium J
l 0-241
Kp.
59-6
BeK3C6N6 . . .
329-3 \
| Crystallized ferricyanide of po- )
I tassium I
[ 0-233
Kp.
76*7
Be K4 06 Ng+ 3 H2 0
422-4 j
[ Crystallized ferrocyanide of po- |
[ tassium J
\ 0-280
Kp.
118-3
g2ci6
237
Between 18° and 37° . . .
0-178
Kp.
42-2
The specific heat between 18° and 43° was found = 0T94; between 18° and 50°
= 0-277.
€10 H8 128 Between -26° and 18° . . 0-3096 A. 39-6
The specific heat of naphthaline was found to be 0-3208 between 0° and 20°, and
0-3208 between 20° and 65°.
G27 H54°2
G46 H92 6^2
. 410
. 676
}
Between —21° and 3°
0-4287
Pr.
175-8
289-8
* Obtained as mass of constant melting-point (2190,8) by fusing equivalent quantities of nitrate of potass
and nitrate of soda.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
177
The first formula is that of one constituent of bees’ wax, cerotic acid ; the second
is that of the other, palmitate of melissyle. In reference to the numbers found for the
specific heat of bees’ wax at higher temperatures, compare the last remark in § 77.
Atomic Specific Atomic
weight. heat. heat.
~ ^ 049 f Crystallized cane-sugar . . . 0-301 Kp. 102-9
12 22 H • • 0 | Amorphous cane-sugar . . . 0-342 Kp. 117-0
€6H1406 .... 182 Mannite 0-324 Kp. 59-1
04H604 .... 118 Succinic acid 0-313 Kp. 36-9
04H606 .... 150 Tartaric acid 0-288 Kp. 43-2
€4H606+H20 . . 168 Racemic acid 0-319 Kp. 53-6
O2H2Ba04 . . . 227 Formate of baryta .... 0-143 Kp. 32-5
02K204+H20 . . 184-2 Neutral oxalate of potass . . 0-236 Kp. 43-5
04H3K08+2H2 0 . 254-1 Quadroxalate of potass . . 0-283 Kp. 71*9
04H5K06. . . . 188-1 Acid tartrate of potass . . . 0-257 Kp. 48-3
€4H4NaK06+4H2O 282-1 Seignette salt 0-328 Kp. 92-5
08Hlo0a0lo+8 H20 450 Acid malate of lime . . . 0-338 Kp. 152-1
The preceding Tables contain the material, obtained experimentally, which serves
as subject and basis for the subsequent considerations on the relations of the specific
heat of solid bodies 'to their atomic weight and composition.
PART Y.— ON THE RELATIONS BETWEEN ATOMIC HEAT AND ATOMIC WEIGHT OR
COMPOSITION.
90. I discuss in the sequel the regularities exhibited by the atomic heats of solid
bodies, the exceptions to these regularities, and the most probable explanation of these
exceptions. In regard to the views which I here develope, much has been already
expressed or indicated in former speculations ; in this respect I refer to the first part
of this paper, in which I have given the views of earlier inquirers as completely as I
know them, and as fully as was necessary to bring out the peculiar value of each. It
is unnecessary, then, to refer again to what was there given ; but I will complete for
individual special points what is to be remarked from an historical point of view.
But before discussing these regularities, the question must be discussed whether the
atomic heat of a given solid substance is essentially constant, or materially varies with
its physical condition. It depends on the result of this investigation, how far it may
with certainty be settled whether the general results already obtained are of universal
validity, or whether exceptions to them exist.
The specific heat of a solid body varies somewhat with its temperature ; but the
variation of the specific heat with the temperature is very small, provided the latter
does not rise so high that the body begins to soften. Taking the numbers obtained by
Regnault for lead, by Dulong and Petit, and by Bede and by Bystkom, for the specific
heats of several metals at different temperatures, the conviction follows that the changes
of specific heat, if not of themselves inconsiderable, are yet scarcely to be regarded in
comparison with the discrepancies in the numbers which different observers have found
2 b 2
178
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
for the specific heat of the same body at the same temperature. At temperatures at
which a body softens, the specific heat does indeed vary considerably with the tempera-
ture (compare for example § 77); but these numbers, as containing already part of the
latent heat of fusion, give no accurate expression for the specific heat, and are altogether
useless for recognizing the relations between this property and the atomic weight or
composition.
Just as little need the small differences be considered which Regnault found for a
few metallic substances according as they were hammered or annealed, hard or soft.
For dimorphous varieties of the same substance, even where there are considerable
differences in the specific gravity, the specific heats have not been found to be materially
different (compare FeS2, § 83 ; T-i©2, § 85; Ca€ 03, § 86). The results obtained with these
substances appear to me more trustworthy than those with graphite and the various
modifications of boron and silicium, which moreover have given partly the same specific
heat for the graphitoidal and adamantine modification of the same element. What
trustworthy observations we now possess decidedly favour the view that the dimorphic
varieties of the same substance have essentially the same specific heat.
91. The view has been expressed that the same substance might have an essentially
different specific heat, in the amorphous and crystalline conditions. I believe that
the differences of specific heat found for these different conditions depend, to by far
the greatest extent, upon other circumstances.
The Tables in § 83 to § 89 contain a tolerable number of substances which have been
investigated both after being melted, and also crystallized ; there are no such differences
in the numbers as to lead to the supposition that the amorphous solidified substance
had a different specific heat to what it had in the crystallized state. No such influence
of the condition has been with any certainty shown to affect the validity of Dulong
and Petit’s, or of Neumann’s law. I may here again neglect what the determinations of
carbon, boron, or silicium appear to say for or against the assumption of a considerable
influence of the amorphous or crystalline condition on the specific heat. Re gn AULT
found (§ 85) that the specific heat of artificially prepared (uncrystalline'?) and crystal-
lized titanic acid did not differ. According to my investigations (§ 48) silicic acid has
almost the same specific heat in the crystallized and in the amorphous condition.
In individual cases, where the specific heat of the same substance for the amorphous
and crystallized modification has been found to be materially different*, it may be shown
that foreign influences affected the determination for the one condition. Such influ-
ences are especially: 1. That one modification absorbed heat of softening at the tem-
perature of the experiment ; that is doubtless the reason why the specific heat of yellow
* De la Rive and Makcet (Ann. de Chim. et de Phys. [2] vol. lxxv. p. 118) found the specific heat of
vitreous to be different from that of opaque arsenious acid, and considered the fact to he essential ; hut their
method was not fitted to establish such a difference. Pape’s view, too (Poggendokff’s Annalen, vol. cxx.
pp. 341 and 342), that it is of essential importance for the specific heat of hydrated sulphates whether the salts
are crystallized or not, does not appear to me to he proved by what he has adduced.
PROFESSOR. KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
179
phosphorus was found to be considerably greater at higher temperatures than that of red
phosphorus, but not at low ones (compare § 82), that the specific heat of amorphous
cane-sugar was found to be decidedly greater than that of crystallized (§ 78), and, ac-
cording to Regnault’s opinion, also that the specific heat of amorphous selenium between
80° and 18° was found much greater ( = 0103) than that of the crystalline, while for
lower temperatures there was no difference in the specific heats of the two substances
(§ 82). 2. That in heating one modification its transition into the other is induced,
and the heat liberated in this transition makes the numbers for the specific heat in-
correct; in § 33 I have discussed the probability that this circumstance, in Regnault’s
first experiments with sulphur, gave the specific heat much too high, and it is possible
that it was also perceptible in the above-mentioned experiments with amorphous sele-
nium. 3. That in immersing heated porous bodies in the water of the calorimeter heat
becomes free (compare § 19) ; I consider this as the reason why Regnault found the
specific heat of the more porous forms of carbon so much greater than that of the more
compact (compare § 36) ; and Regnault himself sees in this the reason why he found
the specific heat of the feebly ignited and porous oxides of nickel and of iron greater
than that of the same oxides after stronger heating (compare § 85).
From the importance of this subject for the considerations to be afterwards adduced,
I have here had to discuss more fully what differences are real and what are only appa-
rent in the numbers found for the specific heat of one and the same substance. Even if
the apparent differences are often considerable, their importance diminishes, if allowance
is made for the foreign influence which may have prevailed. In many cases, on the
other hand, a body in totally different modifications has almost exactly the same
specific heat if these foreign influences are excluded. It may, then, be said that, from
our present knowledge, one and the same body may exhibit small differences with cer-
tain physical circumstances (temperature, different degree of density), but never so great
that they may be taken as an explanation why a body decidedly and undoubtedly forms
an exception to a regularity which might have perhaps been expected for it — provided
that the determination of the specific heat, according to which the body in question
forms an exception, is trustworthy, and kept free from foreign influences.
92. Among the regularities in the atomic heat of solid bodies, that found by Dulong
and Petit for the elements stands foremost. A glance at the atomic heats of the so-
called elements collated in § 82, shows that for by far the greater number the atomic
heats are in fact approximately equal. But the differences in the atomic heats, even of
those elements which are usually regarded as coming under Dulong and Petit’s law,
are often very considerable, even when the comparison is limited to those which are
most easily obtained in a pure state, and even if numbers are taken for the specific heats
which give the most closely agreeing atomic heats. Regnault * sought an explanation
of the differences of the atomic heats of the elements in the circumstance that the latter
could not be investigated in comparable conditions of temperature and density ; further^
that the numbers for the specific heat, as determined for solid bodies, contain, besides
* Annal. de Chim. et de Phys. [2] vol. lxxiii. p. 66, and [3] vol. xlvi. p. 257.
180
PROFESSOR KOPP OjSt THE SPECIFIC HEAT OF SOLID BODIES.
the true specific heat (for constant volume), also the heat of expansion. As specific
heat we can indeed only take the sum of the heats necessary for heating and for expan-
sion. But it is not yet proved that the products of the first, quantity (the specific heat
for constant volume) and the atomic weights would agree better than the atomic heats
now do ; it is only a supposition, and even the very contrary may be possible with
individual substances. Temperature has an influence on the specific heat of solid bodies,
and to a different extent with different bodies. Even in this respect, also, all means are
wanting by which the different temperatures at which bodies are really comparable can
be known, and a comparison made of their atomic heats. The utmost possible is to
determine the specific heat at such a distance from the melting-point that latent heat of
softening can have no influence. It is impossible to say with certainty whether the
atomic heats of bodies compared at other temperatures than those which are nearly
identical (ranging about 90° on each side of 10°) will show a closer agreement. It is not
probable. Changes in the specific heat of solid bodies, so long as they are unaffected by
heat of softening, are small in comparison with the differences which the atomic heats of
individual elements show. And it is well worth consideration that individual elements
(phosphorus and sulphur, e.g.) at temperatures relatively near their melting-points,
have not materially greater specific heats than other elements (iron and platinum,
for example) at temperatures relatively distant from their melting-points, but, on the con-
trary, considerably smaller. As regards the influence of density on the specific heat, it is
undoubtedly certain that the latter may somewhat vary with the former ; but it is equally
so that, in all cases in which substances of undoubted purity were examined and the
sources of error mentioned (§91) excluded, this variation is too inconsiderable to give an
adequate explanation of the differences of the atomic heats found for the various solid
elements.
I need not here revert to the considerations developed in §§ 90 and 91, as to how far
a difference in the physical condition of a solid substance exercises an essential influence
on its specific heat ; for whatever view may be held in reference to this influence, and
generally in reference to the circumstances which alter the specific heat of a substance,
and therewith the atomic heat, this is certain, that there are individual elements whose
atomic heat is distinctly and decidedly different from that of most other elements.
Such elements are, from § 82, first of all boron, carbon, and silicium.
The decision of the question whether these elements really form exceptions to Dulong
and Petit’s law presupposes, besides a knowledge of their specific heat, a knowledge of
their atomic weight also. There can be no exceptions to Dulorg and Petit’s law, if,
regardless of anything which may be in opposition to it, the principle is held to, that the
atomic weights of the elements must be so taken as to agree with this law. As a trial
whether this law is universally applicable, the atomic weights ought rather to be taken as
established in another manner. It may be confessed that the determination of the true
atomic weights by chemical and physico-chemical investigations and considerations is
still uncertain, and many questions are still unanswered the settlement of which may
influence that determination. But there seems now to be no more trustworthy basis
PKOFESSOll KOPP OIST THE SPECIFIC HEAT OF SOLID BODIES.
181
for fixing the atomic weights of the elements than that of taking, as the atomic weights
of the elements, the relatively smallest quantities which are contained in equal volumes
of their gaseous or vaporous compounds, or of which the quantities contained in
such volumes are multiples in the smallest numbers; and no better means appear
to exist for determining the atomic weights of those elements the vapour-densities of
whose compounds could not be determined, than the assumption that in isomorphous
compounds the quantities of the corresponding elements are as the atomic weights of
the latter. On this basis, and using this means, the numbers for the atomic weights
have been determined which are contained in the last column of the Table in § 2,
and are used in § 82 et seq. The atomic weights B=10*9, €=12, Si =2 8, cannot be
changed for others. That the atomic weights of tin and silicium are as 118 to 28, is
further proved by the isomorphism of the double fluorides. But to these atomic weights
correspond atomic heats which are far smaller than those found for most other elements.
From the chemical point of view it is inadmissible to take the atomic weights of
boron, carbon, and silicium * in such a manner as to make their atomic heats agree
with Dulong and Petit’s law. In any case these three elements form exceptions to
Dulong and Petit’s law. The sequel will show that this is the case with many other
elements.
93. In many compounds the regularity is observed, that by dividing their atomic
heat by the number of elementary atoms contained in one molecule of the compound,
a quotient is obtained which comes very near the atomic heat of most of the elements —
that is, 6-4. This is found in the alloys enumerated in § 82, and also in a great number
of compounds of definite proportions. A few of the most important cases may be given
here. For speiscobalt, CoAs2 (compare § 83), this quotient is ^=6*4; for the
chlorine compounds, R Cl and R Cl f , the mean of the atomic heats given in § 84 is
12*8, and the quotient —=Q'4:. Of the chlorine compounds, R Cl2, the mean atomic
heat of all the determinations in § 84 is 18*5, and the quotient ^=6*2. It is also very
near this value in the double chlorides; inZnK2 Cl4 it is ^ =6*2, for R K2 Cl6 (the
mean of the determinations of PbK2 Cl6 and Sn K2C16) it is ~=6T. For bromine
compounds, RBr (both here and in the following examples the means are taken of
the determinations in § 84), H^=6*9; for PbBr2 ^=6*5; for iodine compounds, RI
and RI,^p=6'7, and for the iodine compounds, RI2, ^=6'5.
But this regularity, though met with in many compounds, is by no means quite
* For Begnatjlt’s observation, whether, considering the specific heat which he found for silicium, its atomic
weight is to be so taken that silicic acid contains 2 atoms of silicium to 5 of oxygen, compare Ann. de Chim. et de
Phys. [3] vol. lxiii. p. 30. For Scheekek’s remark, that according to the most probable specific heat of
silicium its atomic weight must be taken so that for 1 atom of silicium there are 3 atoms of oxygen, compare
Poggendoeff?s ‘ Annalen,’ vol. cxviii. p. 182.
+ In the sequel E stands for a uni-equivalental and E a polyequivalental atom of a metal.
182
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
universal. The oxygen compounds of the metals correspond to it in general the less
the greater the number of oxygen atoms they contain as compared with that of metal.
The mean atomic heat of the oxides EG in § 85 is 11T, and the quotient ^=5*6.
The quotient for the oxides R203 and R2 03 (even excluding the determinations of
alumina and boracic acid) is only ?7j?=5*4; for the oxides R02 (even excluding the
determinations for silicic acid and zircon) only ^=4*6 ; for the oxides R03, the mean
of Regnault’s determinations only ~=4-7. Still smaller is the quotient for com-
pounds which contain boron in addition to oxygen ( e . g. for the compounds R B02
(compare § 87) it is only — =4*2; for boracic acid, B2 03, it is only I^=3*3), and also
for compounds which contain silicium in addition to oxygen (it is ^=3*8 for silicic
acid, Si 02, compare § 85), or which contain oxygen as well as hydrogen (for ice, II2 0,
it is only ^=2*9*, compare § 85), or which contain hydrogen and carbon besides
oxygen (e. g. it is only ^=2*6 for succinic acid, 04H6 O4, compare § 89). It may be
said in a few words what are the cases in which this quotient approximates to the
atomic heat of most elements, and what the cases in which it is smaller. It is near 6 ’4
in those compounds which only contain elements whose atomic heats, corresponding to
Dulong and Petit’s law, are nearly = 6*4; it is smaller in compounds which contain
elements not coming under Dulong and Petit’s law and having a much smaller atomic
heat than 6*4, and which are recognized as exceptions to this law, either directly, if
their specific heat has been determined for the solid condition (compare § 92), or in-
directly, if it be determined in the manner to be subsequently described.
94. The determinations of specific heat given in §§ 83 to 89 contain the proofs
hitherto recognized for the law that chemically-similar bodies of analogous atomic con-
stitution have approximately the same atomic heat ; and a considerable number of new ex-
amples of the prevalence of this regularity are given by my determinations. The groups
of analogous compounds need not again be collated, as Neumann has done for a smaller
and Regnault for a larger number of groups and for individual elements contained in
them. What I will here discuss is the prevalence, beyond the limits of our previous
* Considering the atomic heat of liquid water to be 18, Garnier (Compt. Rendus, vol. xxxv. p. 278)
thought that the quotient obtained by dividing the atomic weight by the number of elementary atoms in one
atom of the compound, -U =6, came near the atomic heat of the elements. But it requires no explanation
that, in a comparison with the atomic heats of solid elements and solid compounds, that atomic heat must he
taken for the compound H2 9 which is obtained from the specific heat of ice, and not from that of water.
Garnier is not alone in his error, which is rather to he ascribed to the circumstance that formerly both solids
and liquids were compared, as regards their specific heat, in considerations how this property is influenced
by the composition. Hermann more especially (Nouveaux Memoires de la Societe des Naturalistes de
Moscou, vol. iii. p. 137) compared liquid water with solid compounds, as did also Schroder (Poggendorff’s
* Annalen,’ vol. Iii. p. 279) and L. Gmeein in an early discussion of this subject (Gehler’s ‘ Physicalische
Worterbuch, neue Bearbeitung,’ vol. ix. p. 1942), while he subsequently (Handbuch der Chemie, 4. Aufl., vol. i.
p. 220) more correctly compared the specific and the atomic heat of ice with that of other solid compounds.
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES. 183
knowledge, of the regularity, that compounds of analogous atomic constitution have
approximately the same atomic heat.
To this belongs, first, the existence of this regularity in the case of chemically
similar bodies, which exhibit an analogy of atomic constitution, when their formulae
are written with the atomic weights admitted in recent times for the elements, but
which could not be recognized so long as the equivalents of the elements were taken as
a basis, or the formula written, as by Regnault, with the use of the so-called thermal
atomic weights.
The approximate equality of the atomic heats of analogous nitrates and chlorates, of
the alkalies for example, had been already observed. The same character, the haloid,
is ascribed both to carbonates and to silicates, but as these formulae were formerly
written, an analogy in the composition of chlorates and nitrates, or carbonates and
silicates, could not be assumed. But salts of these four different classes, as well as
arseniates and metaphosphates, have analogous atomic constitutions if we assume the
recent atomic weights. The same salts have then also approximately equal atomic
heats. We get the atomic heat
Of chlorate of potass, K Cl 03, § 88 M* 24*8
„ the nitrates, RN03, in § 88 M 23-0
,, metaphosphate of soda, NaP03, § 88 22T
,, arseniate of potass, KAs03, §88 25-3
„ the carbonates, RG03, § 86 M 207
„ the silicates, RSi03, § 86 M 20'5
The differences in these approximately concordant atomic heats are partly essential
and explainable. I come to this again (§ 95).
According to the more recent assumptions for the atomic weights, certain perchlorates,
permanganates, and sulphates have analogous atomic composition, and these salts have
also approximately equal atomic heats ; this has been found to be
For perchlorate of potass, KC104, § 88 26-3
„ permanganate of potass, K Mn 04, §88 28 -3
„ the sulphates, RS04, named in § 88 . M 26T
But approximate equality in the atomic heat is not only found in such compounds of
analogous chemical composition as have similar chemical character, but also in such as
have totally dissimilar chemical character.
The chemical character of protosesquioxide of iron (magnetic iron ore) is quite different
from that of neutral chromate of potass. Sesquioxide of iron, or arsenious acid, have a
chemical character totally different from nitrates or arseniates, or bodies of similar con-
stitution But for the first-named compounds and for the last-named compounds, as
respectively compared with each other, there is analogy in chemical composition and
approximate equality of atomic heat. The atomic heat has been found to be
* M signifies the mean of all determinations.
2 C
MDCCCLXV.
184
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
For magnetic iron ore, Fe3 04, §85 M 37‘7
„ chromate of potass, K2 Or 04, § 87 M 36‘4
„ sesquioxide of iron, Fe2 03, § 85 M 26-8
„ arsenious acid, As203, § 85 25’3
„ the nitrates, RNG3, named in § 88 23-0
„ arseniate of potass, K As 03, § 88 25-3
But there is even in a more extended sense approximate equality of atomic heat in
bodies of analogous atomic composition. If the formulae of the oxides, R 02 (oxide of
tin for instance) are doubled, they become R2 G4, and are then analogous to those of
the sulphates, R S G4, or of tungstate of lime or of perchlorate of potass and other salts.
To the formulae thus made analogous equal atomic heats correspond. The following
atomic heats have been found : —
Oxide of tin, Sn2 04, compare § 85 . M 27*6
Titanic acid, Ti204, „ M 27’3
The sulphates, R S04, in § 87 M 26T
Tungstate of lime, Ga W 04, compare § 87 27-9
Perchlorate of potass, KC104, compare § 88 26*3
Permanganate of potass, KMnG4, compare § 88 28-3
If the formulae of the oxides, RQ2, are trebled they become R3Oe, analogous to those
of the nitrates RN2G6 (nitrate of baryta, e.g.), and similar salts. Here also approxi-
mately equal atomic heats correspond to the formulae thus made analogous. The atomic
heats are as follows : —
Oxide of tin, Sn3G6, compare § 85 M 41-4
Titanic acid, Ti3 06, „ M 41*0
The nitrates, RN2G6, in § 88 M 38T
Metaphosphate of lime, €a P2 06, compare § 88 39-4
How little the atomic heat of compounds depends on their chemical character may
he proved from a greater series of examples than those adduced in the preceding. It
is, however, unnecessary to dwell upon this. The comparisons and considerations con-
tained in the sequel complete what has here been developed as a proof of the principle
that the atomic heat of bodies is independent of their chemical character.
95. The foregoing comparisons give examples of cases in which bodies of analogous
atomic structure, with a totally different chemical character, have approximately the same
atomic heat ; they show that with reference to the atomic heat, monoequivalent and poly-
equivalent elementary atoms have the same influence, which, indeed, followed already
from Regnault’s comparisons ; that the atomic heat of a substance for its polyfold atomic
formula may be compared with that of another substance for a simple atomic formula.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
185
The preceding contains a generalization of Neumann’s law ; but as certainly as this law
is recognized in the preceding in a more general manner than was formerly assumed, as
little is it universally applicable.
Regnault’s investigations have shown that Neumann’s law is not rigidly valid. Even
for those compounds which contain the same element as electronegative constituent,
and have similar atomic constitution, he found the atomic heats as much as to 9- dif-
ferent from each other*. The reason of this he seeks in the same circumstances, which
in his view prevent a closer agreement in the atomic weights of the elements (com-
pare § 92).
Differences of this kind, and even still more considerable, occur in the atomic heats
of compounds for which greater agreement in these numbers might be expected — of
such compounds, "that is, as contain elements of the same, or almost the same atomic heat
combined with the same other element in the same atomic proportion. To this belongs
the fact that the atomic heat has been found so different (§ 85) for the isomorphous com-
pounds, magnetic iron ore (37*7), chrome iron ore (31 ’2), and spinelle (27*7), and for
alumina (21*3) and for sesquioxide of iron (26‘8). In the atomic heats of such analogous
compounds there are differences for which, or rather for the magnitude of which, as
furnished by our present observations, I know at present no adequate explanation.
But there is another kind of difference in the atomic heats of analogous compounds,
which exhibits a regularity, and for which an explanation can be given. Certain
elements impress on all their compounds the common characteristic, that their atomic
heat is much smaller than that of most analogous compounds. The atomic heat of
boracic acid, B2 03, is only 16-6, while that of most other compounds, R2 03 and R2 03, is
between 25 and 28 (§ 85). The atomic heat of the borates, R B 02, is (§ 87) only 16-8,.
while that of R202, as the mean of the determinations in § 85, is 22*2. The atomic
heat of Rb B2 04 is (§ 87) only 26'5, while that of Ee304 (§ 85) in the mean is 37-7.
Similar results have been obtained for compounds of certain other elements, of carbon
and of silicium for instance, that is, of those elements which in the free state have a
smaller atomic heat than that of most other elements.
This observation leads to the question whether the elements enter into compounds
with the atomic heats which they have in the free state, and in connexion with this,
how far is it permissible to make an indirect determination of the atomic heat of the
elements (in their solid state) from the atomic heats of their (solid) compounds.
96. The assumption that elements enter into compounds with the atomic heats they
have in the free state would be inadmissible, if not only the atomic structure as ex-
pressed by the empirical formula, but also the grouping of the elements to proximate
constituents, as is endeavoured to be expressed by the rational formula, influenced
the atomic heat of the compounds. That the latter is not the case is very probable
from the comparisons made in § 94, where approximately equal atomic heats were
obtained for compounds of analogous empirical formulae, even with the greatest dissi-
* Ann. de Chim. et de Phys. [3] vol. i. p. 196.
2 c 2
186
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
milarity of chemical character. That that, which may be supposed and expressed by the
so-called rational formula in reference to the internal constitution of compounds, does
not affect the atomic heat, becomes more probable from the fact that chemically similar,
and even isomorphous compounds, one of which contains an atomic group in the place
of an individual atom in the other, exhibit dissimilar atomic heats. This is seen, for
instance, in comparing analogous chlorine and cyanogen compounds (Cy=CN); the
latter have far greater atomic heats. Thus the atomic heat
Of chloride of mercury, HgCl2, § 84, is 18'0
„ cyanide of mercury, Hg Cy2, § 89 25'2
„ chloride of zinc and potassium, Zn K2 Cl4, § 84 43’4
„ cyanide of zinc and potassium, Zn K2 Cy4, §89 . . . . . . . 59 '6
In like manner ammonium compounds (Am=N H4) have atomic heats considerably
greater than the corresponding potassium compounds. This is seen from the following
Table : —
Chloride of potassium, K Cl, § 84 M 12’9
„ ammonium, Am Cl, § 84 20-0
Nitrate of potass, KN 03, § 88 M 23*5
„ ammonia, Am N 03, § 88 36*4
Sulphate of potass, K2 Sq4, §87 M 336
„ ammonia, Am2 Sq4, § 87 46-2
97. That undecomposable atoms and atomic groups are contained in compounds with
the atomic heats they have in the free state is further probable from the fact that the
sum of the atomic heats of such atoms, or atomic groups, as when united form a certain
compound, is equal or approximately equal to the atomic heat of this compound. For
many compounds whose elements obey Dulong and Petit’s law, what has been stated
in § 93 contains the proof that the atomic heat of these compounds is equal to the sum
of the atomic heats of the elementary atoms contained in one atom of the compounds.
That this is also observed when atomic groups are supposed to be united, forming
more complicated compounds, will be seen by bringing forward a few examples. The
atomic heat has been found
For the oxides, BO, enumerated in § 85 M 11T
„ sesquioxide of iron, Fe2 03, § 85 M 26*8
Sum for Fe2 R04 . . . 37-9
„ magnetic iron ore, Fe3 04, § 85 M 37*7
„ the oxides, B0, in § 85 M 11T
„ the acids, R 03, in § 85, according to Regnault .... M 18-8
Sum for R R 04 . . . 29-9
„ chromate of lead, Pb0r04, §87 29’0
PEOFESSOE KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
187
For the oxides named in § 85, SO M 111
„ binoxide of tin, Sn 02, § 85 M 13-8
SumforRR03 . . . 24-9
„ sesquioxide of iron, Fe2 03, §85 M 26*8
„ chromate of potass, K2€r04, § 87 M 36 '4
„ the acids, R03, in § 85 (Regnault) 18-8
Sum for K2€rRG7 . . . 55*2
„ acid chromate of potass, K2€r2 07, § 87 M 55-3
„ binoxide of tin, Sn306, § 85 M 41*4
„ base, R2 02, mean of determinations, § 85 M 22*2
SumforSgOg . . . 63*6
„ arseniate of lead, Pb3 As208, § 88 65-4
To this belongs the fact that water is contained in solid compounds with the atomic
heat of ice*. The different determinations of the specific heat of this substance (§ 85)
gave the atomic heat for greater distances from 0°, 8-6, and for temperatures nearer 0°, 9T
to 9*2. The atomic heats have been found
For BaCl2+2H20, §84 41*7 ForH20.
„ the chlorides, R Cl2, § 84 M 18-5
Remains for 2 H2 0 . . . 23-2 11-6
,, OaCl2+6 H2 O, § 84 75*6
„ the chlorides, R Cl2, § 84 M 18-5
Remains for 6 H2 O . . . 57T 9-5
„ Brucite, Mg G-j-H2 0, § 85 18-1
„ the oxides, R O, § 85 M 11 1
Remains for H2 O . . . . 7‘0 7"0
„ dioptase, €uSi03+H20, § 86 28-7
„ the silicates, R Si 03, § 86 M 205
Remains for H2 O . . . . 8-2 8-2
„ Na2B4O7+10H2O, § 87 146-9
„ Na2B497, §87 47T
Remains for 10 H2 O . . . 99-8 10-0
» gypsum, €aS04+2H20, § 87 M 45-8
„ the sulphates, RS04, § 87 M 26-1
Remains for 2 H2 O . . . 19-7 9-9
* Even before Person (compare § 14) L. Gmelin bad speculated (Handbucb der Chemie, [4] Aufl. vol. i.
p. 223) whether from the atomic heats of anhydrous sulphate of lime and of ice that of gypsum could be calcu-
lated. The results of calculation deviated considerably from the atomic heat as deduced from the observed specific
heat of gypsum ; the specific heat, and therewith the atomic heat of ice, were at that time incorrectly known.
188
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
The Tables in § 84 to 89 contain data for several such comparisons, which lead to
the same result as the preceding — that the atomic heat of water contained in solid com-
pounds may, by subtracting the atomic heat of the anhydrous solid from that of the
hydrated solid compound, be obtained in sufficient approximation to the atomic heat
deduced from the direct determination of the specific heat of ice. The deviations from
each other and from the atomic heat of ice as directly determined, which these indirect
determinations exhibit, are not to be wondered at when it is considered that all uncer-
tainties in the atomic heats, from whose difference the atomic heat of solid water is
deduced, are concentrated upon this difference.
98. The view already expressed and defended (compare especially § 12 and 13), that
atoms and atomic groups are contained in solid compounds with the same atomic heat
which they have in the free state, is opposed to the view which has also been frequently
expressed and defended — that the atomic heat of an element may in certain com-
pounds differ from what it is in the free state, and may be different in different com-
pounds. This view, and the reasons which may possibly be urged in its favour, must
here be discussed.
The first statement of this view (compare § 6) simply goes to assert that the atomic
heats of compounds may be calculated in accordance with the values resulting from the
determinations of the specific heat, assuming that one constituent of the compound has
the same atomic heat as in the free state, the other an altered one. What alteration is
to be assumed depends merely on what assumption adequately satisfies the observed
specific heat of the compound. The accuracy of the assumption is susceptible of no
further control ; the assumption itself cannot be regarded as an explanation of the
observed atomic heat of the compound. And nothing is altered in this by assuming
(compare § 6 and 11) that the changes in the atomic heat of a substance on entering
into chemical compounds take place in more or less simple ratios.
A greater degree of probability must be granted to the view (compare § 10) that the
atomic heats of the constituents of compounds, and the differences in the atomic heats
of these bodies, according as they are combined or in the free state, depend upon the
state of condensation in which these bodies are contained. If, for instance, from a
consideration of the specific gravities or specific volumes (the quotient of the specific
weights into the atomic weights) of compounds and of their constitutents, a conclusion
could be drawn with some degree of certainty as to the state of condensation in which
the latter are present in the former, and if definite rules could be given for the varia-
tions of the atomic heats with the state of condensation, the result of such an investiga-
tion, if it agreed with the observed results for the atomic heats of compounds, might be
called an explanation of these observations. But what is here presupposed is partially
not attained and partially not attempted. And, moreover, as far as can be judged
from individual cases, the same element, when contained in different states of condensa-
tion, appears to have the same atomic heat. It has been attempted to deduce the state
of condensation, or the specific volume of oxygen in its compounds with heavy metals,
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLED BODIES.
189
by subtracting from the specific volume of the oxide that of the metal in it, and con-
sidering the remainder as the volume of oxygen. It would follow from this that the
specific volume of oxygen in suboxide of copper is much greater (about four times as
great) than in oxide of tin. But if the atomic heat of oxygen be deduced by sub-
tracting from the atomic heat of the oxide that of the metal in it, it is found that the
atomic heat of oxygen in suboxide of copper and in oxide of tin gives almost exactly
the same number. Hence it does not seem that the state of condensation in which a
constituent may be contained in a compound has any material influence on the atomic
heat of this constituent.
99. From all that has been said in the foregoing paragraphs the following must be
adhered to. (1) Each element in the solid state, and at a sufficient distance from its
melting-point, has one specific or atomic heat, which may, indeed, somewhat vary with
physical conditions, different temperature, or density for instance, but not so consider-
ably as to be regarded in considering in what relations the specific heat stands to the
atomic weight or composition; and (2) that each element has essentially the same
specific or atomic heat in compounds as it has in the free state. On the basis of these
two fundamental laws it may now be investigated what atomic heats individual elements
have in the solid free state and in compounds. Indirect deductions of the atomic
heats of such elements as could not be investigated in the solid free state are from
these propositions admissible : that from the atomic heat of a compound containing such
an element the atomic heat of everything else in the compound is subtracted, and the
remainder considered as the expression for the atomic heat of that element. Such in-
direct determinations of the atomic heat of elements may be uncertain, partly because
the atomic heat of the compounds is frequently not known with certainty, as is seen
from the circumstance that analogous compounds, for which there is every reason to
expect the same atomic heat, are found by experiment to have atomic heats not at all
agreeing ; but more especially because the entire relative uncertainty in the atomic
heats for a compound, and for that which is to be subtracted from its composition, is
concentrated upon a small number, the residue remaining in the deduction. But
when such deductions are made, not merely for individual cases, but for different com-
pounds, and for entire series of corresponding compounds, they may be considered suffici-
ently trustworthy to make the speculations based upon them worthy of attention. Of
course in indirectly deducing the atomic heat of an element, its simpler compounds,
and those containing it in greatest quantity (measured by the number of atoms), promise
the most trustworthy results.
100. For Silver , Aluminium , Arsenic , Gold, Bismuth, Bromine , Cadmium, Cobalt,
Copper, Iron, Mercury , Iodine, Iridium, Potassium, Lithium, Magnesium , Manganese,
Molybdenum, Sodium, Nickel, Osmium, Lead, Palladium, Platinum, Rhodium, Antimony,
Selenium, Tin, Tellurium, Thallium, Tungsten, and Zinc, it may be assumed, from the de-
terminations of their specific heat in the solid state (§ 82), that their atomic heats, in
190
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
accordance with Dulong and Petit’s law, are approximately equal, the average being 6‘4.
I do not think that all these elements have really the same atomic heat, but think that
some of them will subsequently be considered as exceptions to the above-mentioned
law, as it will in the sequel be proved that several elements have an atomic heat differing
from 6 ’4. But for none of the previously mentioned elements are the present data,
and the presumed deviation of the atomic heat from that of other elements, sufficient to
justify their being separated from them.
To the elements just mentioned chlorine must be associated from the close agreement of
the corresponding chlorine, bromine, and iodine compounds (§ 84), and of the compounds
K Cl 03, 24*8, and K As 03, 25’3 (§ 88). To the atomic heats of these latter compounds
those of individual salts KN03 approximate closely; the latter gave (§ 88) 21*8-24’4,
mean 2S,0, which on the whole agrees sufficiently closely with those found for the
metallic oxides, B2 03 (§ 85). I count nitrogen also among the elements whose atomic
heat may be assumed at 6'4, like that of most other elements; without, however, con-
sidering the determination of the atomic heat of this element as very trustworthy. To
deduce the atomic heat of this element with certainty, compounds are wanting which
contain, besides nitrogen, elements whose atomic heat has been directly determined.
The fact that the atomic heat of the nitrates, R2 N2 ©6, was found (§ 88) in the mean
to be 38T, a third of which, 12‘7, is somewhat less than the average atomic heat
found for the oxides of heavy metals of the formula R 02, might be a reason for assign-
ing to nitrogen a smaller atomic heat ; while, on the other hand, the atomic heats of
other nitrogen compounds, in which it is true other elements enter whose atomic heat is
only indirectly determined, do not favour this view.
In the class of elements with the atomic heat about 6 '4, barium , calcium , and
strontium may be placed from the agreement in the atomic heats of their compounds
with the atomic heats of corresponding compounds of such elements as have been
found by the direct determination of their specific heat in the free solid state to belong
to that class (compare the atomic heats of the compounds RC12 in § 84, R©03in
§ 86, R S04 in § 87, and SN2G6 in § 88); further, rubidium (compare the atomic
heats of the compounds B Cl in § 84, and R2 € 03 in § 86) ; then also chromium (from
the agreement in the atomic heats of Cr2 03 and ¥e2 03, § 84), and titanium (from the
agreement in the atomic heats of Ti 02 and Sr 02, § 84). To place zirconium in the same
class has no other justification than that on this assumption the atomic heat of zircon
may be calculated in accordance with that deduced from the observed specific heat of
this mineral.
101. According to direct determinations of the specific heat, sulphur and phosphorus
do not belong to this class. The more trustworthy determinations (for sulphur the last
two, for phosphorus the last three of the numbers in § 82) assign to these elements the
atomic heat 5 '4. That sulphur has a smaller atomic heat than the elements discussed
in the last paragraphs follows from the atomic heats of sulphur compounds, compared
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
191
with those of the corresponding compounds of such elements as have an atomic heat
= 6'4. The average atomic heat of compounds RS and RS is 11*9, according to the
determinations in § 83, while those of chlorine compounds RC1 and R Cl (§ 84) =12*8,
that of the corresponding bromine compounds =13*9, and of the corresponding iodine
compounds =13*4. In comparing more complicated sulphur compounds, sulphates, for
instance, with other compounds of analogous composition, the same is met with ;
although such complicated compounds are of little value in giving data for deciding on
such small differences. The specific heat of the simpler phosphorus compounds has not
been investigated ; for more complicated compounds, although they point to a smaller
atomic heat for P than 6-4, the above remark also applies.
The determinations of the specific heat of silicium give for this element also a smaller
atomic heat than 6*4 (compare § 82), and the same conclusion results from a comparison
of the atomic heats of Si 02, and the oxides, R 02, of the silicates R Si 03, and the oxides
R2 03. The atomic heat to be assigned to silicium cannot as yet be settled with any
degree of certainty. Direct determinations, varying considerably from each other, give
a specific heat mostly greater than 4; while the numbers obtained indirectly, and them-
selves also not closely agreeing, are partly considerably smaller. If in the sequel I put
the atomic heat of silicium at 3*8, corresponding to the lowest number found for the
specific heat of this element, I do so for want of other and more certain data. I con-
sider this number as quite uncertain.
The atomic heat of boron , from the direct determinations of the specific heat, is con-
siderably smaller than 6 *4 ; and the atomic heats of boron compounds confirm this, as
was discussed in §§ 93 and 95. By comparing the atomic heats of such boron and sul-
phur compounds as contain along with boron and sulphur the same elements in the
same proportions, the atomic heat of boron is found to be half that of sulphur. The
atomic heat of KB02=16*8 is exactly half that found for K2B04=33*6; the atomic
heat of BbB204 = 26’5 is almost exactly equal to that for RbS04=25*7. Taking the
atomic heat of S, in accordance with the above discussion, at 5-4, that of B would be
2 ’7; the numbers obtained directly for the atomic heat of boron (§ 82) from the expe-
riments on the specific heat of this element agree with sufficient accuracy. In the sequel
I take the atomic heat of B at 2-7. A smaller number is obtained in other compari-
sons ; for instance, of the atomic heats of B2 03 and of the oxides R2 03, or of the salts
R B 02 and the oxides R2 02 ; but in such indirect determinations of the atomic heat,
where such small numbers are to be determined, as is here the case with the atomic heat
of boron, the results are very uncertain, owing to the fact that the entire uncertainty in
the atomic heats of the compounds, and in the assumption that the elements correspond-
ing to boron in compounds of analogous composition have really the atomic heat, =6*4,
is thrown on the final result.
Lastly, carbon also, from the direct determinations of its specific heat (§ 82), has a
much smaller atomic heat than 6 ’4. The same result follows from a comparison of the
atomic heats of carbon compounds : the atomic heat of the carbonates, R2 € 03=28,4 as
mdccclxv. 2 D
192
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
the mean of the determinations in § 86, is much smaller than that of R303(==3R0),
which is the mean of the numbers in § 85 =33*3; the atomic heat of the carbonates
RG03 =20*7, as the mean of the determinations in § 86, is much smaller than 27*1,
the number found for As2 03, Bi293, Gr2 03, Fe203, and Sb203 as the atomic heat of
oxides R203. I put the atomic heat of carbon at T8 for G, as deduced from the deter-
mination of the specific heat of its purest variety, diamond.
102. In the preceding paragraphs I have discussed the elements which, from the
determinations of their specific heat in the solid free state, have a smaller atomic heat
than about 6-4. There remain to be discussed a few elements whose atomic heats are
also less than those of most other elements, but can only be deduced from those of their
compounds.
To this category belongs hydrogen *, even if the indirect determination of its atomic
heat in the solid state is liable to the uncertainty just discussed. The atomic heat of
water, H20, is (§ 85) =8*6, and smaller by 7 than that of suboxide of copper, Gu20,
which was found in the mean to be 15*6 ; the atomic heat of hydrogen would thus be
-|=3 '5 less than that of the elements to which copper belongs, as regards its atomic
heat ; hence the former would be 6'4 — 3-5 = 2’9. The atomic heat of chloride of ammo-
nium, N H4 Cl, has been found to be 2(M) (§ 84) ; the subtraction of the atomic heats for
N+ Cl=6-4+6-4=12'8, leaves 7’2 as the atomic heat of 4H, and therefore T7 for that
of H. The atomic heat of nitrate of ammonia, N2H4G3, is 36-4 (§ 88); subtracting
therefrom as the atomic heat of N2+03, the number 27T, which has previously been fre-
quently mentioned as the atomic heat of oxides R203, we haye 9 -3 as the atomic heat
of 4H, that is 2‘3 for that of H. I put in the sequel the atomic heat of hydrogen at 2'3.
That oxygen has a smaller atomic heat than 6*4, follows from the fact that the oxygen
compounds of the metals have a considerably smaller atomic heat than the correspond-
ing chlorides, iodides, or bromides. For instance, the atomic heat of the oxides -R0 is
as the mean of the determinations in § 85 =11T, while that of the chlorides RC1 and
RC1 (§ 84), is 12’8, that of the corresponding bromides 13‘9, and of the corresponding
iodides 13’4. That of the oxides, R02, as the mean of the determinations in § 85, of
. Mn02, Sn02, and Ti02 is 13*7, while that of the chlorides RC12 (§ 85) is 18*5, and
of the iodides Rl2=19’4. Taking the atomic heat of the other elements, which are
contained in the following compounds, at 6-4, the atomic heat of oxygen, as deduced
from the atomic heat of the oxides R 0 (11T in the mean), is =4*7 ; as deduced from
the oxides B2 03 (27T as the mean of the oxides of this formula previously frequently
mentioned), it is =4-8; from the above oxides, R02 (13*7 in the mean), it is =3-7; it is
found (compare § 88) from K As 03 (25-3) to be 4T; from Pb3 As2 08 (65-4) to be 4*2;
from KC103 (24-8) to be 4-0; from KC104(26‘3) to be 3*4; from K-Mn04 (28’3) to
be 3 ’9. In the sequel I take the round number 4 for the atomic heat of 0.
* L. Gmelin (Handbuch der Chemie, 4 Aufl. vol. i. pp. 216 and 222) ascribed to hydrogen the same
capacity for heat as that of an equivalent quantity of lead or mercury (H=l, Cu=31-7, Hg=100); Schroder
(Poggend. Ann. vol. lii. p. 279) and Cannizzaro (II Nuovo Cimento, vol. vii. p. 342) ascribed to hydrogen the
same atomic heat as that of most other elements (H=l, Cl=35-5, €hi=63*4, Hg=200).
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
193
Fluorine appears, lastly, to have a considerably smaller atomic heat than 6*4. The
atomic heat of fluoride of calcium, Ga Fl2, has been found to be (§ 84) only 16 '4, con-
siderably smaller than the corresponding chlorides, bromides, and iodides. I put the
atomic heat of fluorine at 16'4~6'4=5.
103. Taking, in accordance with what has just been said, the atomic heat which an
element has in a solid compound,
At 6*4 for Ag, Al, As, Au, Ba, Bi, Br, Ga, Gd, Cl, Go, Gr, Gu, Be, Hg, I, Fr, K, Li,
Mg, Mn, Mo, N, Na, M, Os, Bb, Pd, Ft, Bb, Bh, Sb, Be, Bn, Sr, Te, Ti, Tl, W,
Zn, and Zr,
At 5-4 for S and P, at 5 for FI, 4 for O, 3-8 for Si, 2*7 for B, 2-3 for H, and 1*8 for G ;
and assuming that the atomic heat of a solid is given by the sum of the atomic
heats of the elements in it, we obtain the atomic heats ; and dividing them by the atomic
weights, we obtain the specific heats, in sufficiently close agreement with the specific
heats as obtained by direct determinations of this property.
In the following Table I give for all compounds for which the specific heat has been
determined in a trustworthy manner, the specific heat calculated on these assumptions,
compared with the numbers found experimentally. I give this calculation and this com-
parison in the same order which was followed in the synopsis § 82 to 89, and I refer
to the latter as regards special remarks on the determinations. To distinguish the
observers, N. again stands for Neumann, B. Begnault, Kp. Kopp, Pr. Person, A. Al-
luard, and Pp. Pape.
Alloys. (Compare § 82.)
At *
Atomic
Atomic
Specific
Specific
heat.
heat.
heat.
° Calculated. Calculated.
Observed.
Bi Bn . . .
. . 328
12-8
0-0390
0-0400
B.
BiSn2 . . .
. . 446
19-2
0-0430
0-0450
B.
Bi Sn2 Sb . .
. . 568
25-6
0-0451
0-0462
K.
Bi Sn2, Sb Zn2
. . 698-4
38-4
0-0550
0-0566
B.
PbSb . . .
. . 329
12-8
0-0389
0-0388
B.
PbSn . . .
. . 325
12-8
0-0394
0-0407
B.
PbSn2 . . .
. . 443
19-2
0-0433
0-0451
B.
104. Arsenides and Sulphides. (Compar
CO
qo
•O’
GoAs2 . . .
. . 208-8
19-2
0-0919
0-0920
N.
Ag2B . . .
. . 248
18-2
0-0734
0-0746
B.
GoAsS . .
. . 166
18-2
0-110
0-107
N.
Gu2B . . .
. . 158-8
18-2
0-115
0-121
B.
0-120
Kp.
Fe As B . .
. . 163
18-2
0-112
0-101
N.
AsB . . .
. . 107
11-8
0-110
0-111
N.
GoB . . .
. . 90-8
11-8
0-130
0-125
B.
Gui. Per. B . .
. . 91-7
11-8
0-129
0-129
N.
0-131
Kp.
Fe B . . .
. . 88
11-8
0-134
0-136
B.
HgS . . .
. . 232
11-8
0-0509
0-052
N.
0-0512
B.
NiS . . .
. . 90-8
11-8
0-130
0-128
B.
2 d 2
194
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
•
Atomic
Specific
Specific
beat.
beat.
beat.
w eigut. Qa^cu]a|;e(j- Calculated. Observed.
Pb s . . .
. . 239
11-8
0-0494
0-053
N. 0-0509
R.
0-0490
Sn S ...
. . 150
11-8
0-0787
0-0837
K.
ZnS . . .
. . 97*2
11-8
0-121
0-115
N. 0-123
R.
0-120
Fe7 S8 . . .
. . 648
88-0
0-136
0-153
N. 0-160
R.
As„ Bo .
. . 246
29-0
0-118
0-113
N.
Bi2S3 . . .
. . 516
29-0
0-0562
0-060
K.
Sb9S3 . . .
. . 340
29-0
0-0853
0-0907
N. 0-0840
R.
Fe B2 . . .
. . 120
17-2
0-143 0-128-0-133 N. 0-130
R.
0-126
Mo So • . •
. . 160
17-2
0-107
0-107
N. 0-123
R.
Sn S2 . . .
. . 182
17-2
0-0945
0-119
K.
105.
Chlorides , Bromides , Iodides , and Fluorides. (Compare § 84.)
Ag Cl . . .
. . 143-5
12-8
0-0892
0-0911
R.
Cu Cl . . .
. . 98-9
12-8
0-129
0-138
K.
Hg Cl . . .
. . 235-5
12-8
0-0543
0-0521
K.
K Cl . . .
•. . 74-6
12-8
0-172
0-173
K. 0-171
Kp.
Li Cl . . .
. . 42-5
12-8
0-301
0-282
R.
NaCl . . .
. . 58-5
12-8
0-219
0-214
R. 0-213-0-219 Kp.
Kb Cl . . .
. . 120-9
12-8
0-106
0-112
Kp.
N H4 Cl . .
. . 53-5
22-0
0-411
0-373
Kp.
Ba Cl2 . . .
. . 208
19-2
0-0923
0-0896
R. 0-0902
Kp.
Ca Cl2 .
. . Ill
19-2
0-173
0-164
R.
HgCl2. . .
. . 271
19-2
0-0708
0-0689
R. 0-640
Kp
MgCl2. . .
. . 95
19-2
0-202
0-195
R. 0-191
Kp.
Mn Cl2 . .
. . 126
19-2
0-152
0-143
R.
PbCl2 . . .
. . 278
19-2
0-0691
0-0664
R.
Sn CL . . .
. . 189
19-2
0-102
0-102
R.
Sr Cl2 . . .
. . 158-6
19-2
0-121
0-120
R.
ZnCl2 . . .
. . 136-2
19-2
0-141
0-136
R.
BaCl2+2H2G
. . 244
36-4
0-149
0-171
Kp.
CaCl2+6H20
. . 219
70-8
0-323
0-345
Pr.
Zn K2 Cl4 . .
. . 285-4
44-8
0-157
0-152
Kp.
Pt K2 Cl6 . .
. . 488-6
57-6
0-118
0-113
Kp.
Sn K2 Cl6 . .
. . 409-2
57-6
0-141
0-133
Kp.
Cr2 Cl6 . .
. . 317-4
51-2
0-161
0-143
Kp.
Ag Br . . .
. . 188
12-8
0-0681
0-0739
R.
K Br . . .
. . 119-1
12-8
0-107
0-113
R.
Na Br . . .
. . 103
12-8
0-124
0-138
R.
Pb Br2 . . .
. . 367
19-2
0-0523
0-0533
R.
Agl . . .
. . 235
12-8
0-0545
0-0616
R.
Cu I ...
. . 190-4
12-8
0-0672
0-0687
R.
Kg I . . .
. . 327
12-8
0-0391
0-0395
R.
K I ....
. . 166-1
12-8
0-0771
0-0819
R.
Na I ...
. . 150
12-8
0-0853
0-0868
R.
Hgl2 . . .
. . 454
19-2
0-0423
0-0420
R.
Pbl2 . . .
. . 461
19-2
0-0416
0-0427
R.
Ca Fl2 . . .
. . 78
16-4
0-210
0-208
N. 0-215
R.
0-209
A1 Na3 Fig
. . 210-4
55-6
0-264
0-238
Kp.
Kp
Kp
Kp
Kp.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
195
106. Oxides. (Compare § 85.)
.
Atomic
Atomic
Specific
Specific
heat.
heat.
heat.
weig t. Qajcu2ated. Calculated. Observed.
Gu2 0
142-8
16-8
0-118
0-107
N.
0-111
Kp.
H20
18
8-6
0-478
0-480
Pr.
0-474
E.
Gu0
79-4
10-4
0-131
0-137
N.
0-142
E.
0-128
Kp.
Hg0
216
10-4
0-0481
0-049
N.
0-052
E.
0-053
Kp.
Mg 9
40
10-4
0-260
0-276
N.
0-244
E.
MnO
71
10-4
0-146
0-157
E.
IO
74-8
10-4
0-139
0-159
E.
Pb0
22-8
10-4
0-0466
0-0512
E.
0-0553
Kp.
ZnO
81-2
10-4
0-128
0-132
N.
0-125
E.
Mg'0+H,0 . .
58
19-0
0-328
0-312
Kp.
Fe304
232
35-2
0-152
0-164
N.
0-168
E.
0-156
Kp.
Mg Al2 04 . . . .
142-8
35-2
0-246
0-194
Kp.
Mgi Fei Gr| AL 04 .
196
35-2
0-179
0-159
Kp.
Alg 03
102-8
24-8
0-241
0-197
N.
0-217
E.
As203
198
24-8
0-125
0-128
E.
B203
69-8
17-4
0-249
0-237
E.
Bi203
468
24-8
0-0530
0-0605
E.
Gr203
152-4
24-8
0-163
0-196
N.
0-180
E.
0-177
Kp.
Fe203
160
24-8
0-155
0-169
N.
0-167
E.
0-154
Kp.
BerTi!03 . . .
155-5
24-8
0-160
0-176
N.
0-177
Kp.
Sb203
292
24-8
0-0849
0-0901
E.
Mn203+H20 . .
176
33-4
0-189
0-176
Kp.
Mn02. . . . .
87
14-4
0-166
0-159
Kp.
Si©2
60
11-8
0-197
0-188
N.
0-191
E.
0-186
Kp.
Si’. ZriO, ....
90-8
13-1
0-144
0-146
E.
0-132
Kp.
fin©,’ .....
150
14-4
0-096
0-093
N.
0-093
E.
0-089
Kp.
Ti©2
82
14-4
0-176
0-172
N.
0-171
E.
0-159
Kp.
Mo03
144
18-4
0-128
0-132
E.
0-154] Kp.
W03
232
18-4
0-0793
0-0798
E.
0-0894] Kp.
107. Carbonates and Silicates. (Compare § 86.)
K2G03 ....
138-2
26-6
0-192
0-216
E.
0-206
Kp.
Na2G03 ....
106
26-6
0-251
0-273
E.
0-246
Kp.
Eb2 C 03 ....
230-8
26-6
0-115
0-123
Kp.
BaG03 ....
197
20-2
0-103
0-108
N.
0-110
E.
GaG03 ....
100
20-2
0-202
0-203
N.
0-209
E.
0-205
Kp.
0aiMgx003
92
20-2
0-220
0-216
N.
0-218
E.
0-206
Kp.
EelMnyMgyG03
112-9
20-2
0-179
0-166
Kp.
Mg|Be|003 . .
91-1
20-2
0-222
0-227
N.
Pb G 03 . . . .
267
20-2
0-0757
0-0814
N.
0-0791
Kp.
Sr G 03 . . . .
147-6
20.2
0-137
0-145
N.
0-145
E.
Ga Si 03 . . . .
116
22-2
0-191
0-178
Kp.
Gai Mgi. Si 03 . .
108
22-2
0-205
0-191
N.
0-186
Kp.
GuSi03+H20. .
157-4
30-8
0-195
0-182
Kp.
Mgfi£eTySi04 . .
145-8
32-6
0-223
0-206
N.
0-189
Kp.
A-l2 K2 Si6 016 . .
557
112-4
0-202
0-191
N.
0-183
Kp.
Al2Na2Si6016 . .
524-8
112-4
0-214
0-196
N.
0-190
Kp.
196 PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
108. Borates , Molybdates , Tungstates , Chromates , and Sulphates. (Compare § 87.)
•
Atomic
Atomic
Specific
Specific
heat.
heat.
heat.
° L' Calculated. Calculated. Observed.
K B 02 ....
82
17-1
0-209
0-205
R.
NaBG2 ....
65-9
17-1
0-260
0-257
R.
Pb B2 04 ....
292-8
27-8
0-0949
0-0905
R.
P-bB4G7 ....
362-6
45-2
0-124
0-114
R.
K2B4G7 ....
233-8
51-6
0-221
0-220
R.
Na9B4G7 . . .
201-6
51-6
0-256
0-238
R. 0-229
Kp.
Na9 B4G7-f-10H9G
381-6
137-6
0-366
0-385
KP.
Pb MoG4 ....
367
28-8
0-0785
0-0827
Kp.
GaWG4 ....
288
28-8
0-100
0-0967
Kp.
-Fes. Mns W G4 . .
303-4
28-8
0-0949
0-0978
R. 0-0930 Kp.
Pb Cr G4 ....
323-2
28-8
0-0891
0-0900
Kp.
K2 Gr G4 ....
194-4
35-2
0-181
0-185
R. 0-189
Kp.
K2 Gr2G7 ....
294-6
53-6
0-182
0-189
R. 0-186
Kp.
khsg4 ....
136-1
30-1
0-221
0-244
Kp.
K38G4 ....
174-2
34-2
0-196
0-190
R. 0-196
Kp.
Na9SC4 ....
142
34-2
0-241
0-231
R. 0-227
Kp.
N2H8SG4 . . .
132
52-6
0-398
0-350
Kp.
Ba S G4 ....
233
27-8
0-119
0-109
N. 0-113
R.
0-108
Kp.
GaSG4 . . . .
136
27-8
0*204
0-197
R. 0-185
N.
0-178
Kp.
Cu£G4 ....
159-4
27-8
0-174
0-184
Pp.
-Mg S G4 ....
120
27-8
0-232
0-222
R. 0-225
Pp.
M-n B G4 ....
151
27-8
0-184
0-182
Pp.
Pb SG4 ....
303
27-8
0-0917
0-0872
R. 0-0848
N.
0-0827 Kp.
SrSG4 ....
183-6
27-8
0*151
0-143
R. 0-136
N.
0-135
Kp.
ZnSG4 ....
161-2
27-8
0-172
0-174
Pp-
€uSG4+H2G . .
177-4
36-4
0-205
0-202
Pp-
Mg£G4+H2G . .
138
36-4
0-264
0-264
Pp.
Zn-SG4 + H2G . .
179-2
36-4
0-203
0-202
Pp.
GaSG4 + 2H9G .
172
45-0
0-262
0-273
N. 0-259
Kp.
€uSG4+2H2G .
195-4
45-0
0-230
0-212
Pp.
Zn-SG4 + 2H2G .
197-2
45*0
0-228
0-224
Pp.
Fe£G4+3H2G .
206
53-6
0-260
0-247
Pp.
GuBG4+5H9G .
249-4
70-8
0-284
0-285
Kp. 0-316
Pp.
MnSG4+5H2G .
241
70-8
0-294
0-323
Kp. 0-338
Pp.
MSG4 + 6H2G .
262-8
79-4
0-302
0-313
Kp.
GoSG4+7H9G .
280-8
88-0
0-313
0-343
Kp.
Fe£G4 + 7H9G .
278
88-0
0-317
0-346
Kp. 0-356
Pp.
MgSG4 + 7H2G .
246
88-0
0-358
0-362
Kp. 0-407
Pp.
MSG4+7H2G .
280-8
88-0
0-313
0-341
Pp.
ZnSG4+7 H2 G .
287-2
88-0
0-306
0-347
Kp. 0-328
Pp.
Mg K2 B2 G8 + 0 H2G
402-2
113-6
0-282
0-264
Kp.
m K2S2G8+6H2G
437
113-6
0-260
0-245
Kp.
Zn K9 B9Go+6 H9G
443-4
113-6
0-256
0-270
Kp.
-ALKoB.G, + 24 H9G 949
317-6
0-335
0-371
Kp.
Gr2K2S4G16 + 24 H2G 998-6 317*6
0-318
0-324
Kp.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
197
109. Arseniates,
Phosphates, Pyrophosphates and Metaphosphates, Nitrates, Chlorates ,
Perchlorates, and Permanganates. (Compare § 88).
Atomic
weight.
Atomic Specific Specific
heat. heat. heat.
Calculated. Calculated. Observed.
KAsOg ....
162*1
24-8
0-153
0-156
R.
K H2 As 04 . . .
180-1
33-4
0-185
0T75
Kp.
Pbo As2 Ofi . . .
899
64-0
0-0712
0-0728
R.
Ag3P04 ....
419
40-6
0-0969
0-0896] Kp.
kh2po4 . . .
136-1
32-4
0-238
0-208
Kp.
Na2HP04+12H2G
358
139-7
0-390
0-408
Pr.
Pb3P208 ....
811
62-0
0-0764
0-0798
R.
K4P207 ....
330-4
64-4
0-195
0T91
R.
Na4P207 ....
266
64-4
0-242
0-228
R.
Pb2P907 ....
588
51-6
0-0878
0-0821
R.
NaP03 ....
102
23-8
0-233
0-217
Kp.
CaP206 ....
198
41-2
0-208
0T99
R.
AgNOg ....
170
24-8
0-146
0T44
R.
KNOg ....
101-1
24-8
0-245
0-239
R.
KiNarNOg . . .
93
24-8
0-267
0-235
Pr.
NaNOg . . . .
85
24-8
0-292
0-278
R.
N2H4Og ....
80
34-0
0-425
0-455
Kp.
Ba N2 06 ....
261
43-2
0-166
0-152
R.
Pb N2 06 ....
331
43-2
0-130
0-110
Kp.
-SrN206 . . . .
211-6
43-2
0-204
0-181
Kp.
K Cl Og . . . .
122-6
24-8
0-202
0-210
R.
BaCl206+H20 .
322
51-8
0-161
0-157
Kp.
K Cl ©4 . . . .
138-6
28-8
0-208
0-190
Kp.
KMn04 ....
158-1
28-8
0T82
0-179
Kp.
Kp.
Kp.
Kp.
Kp.
110. Organic Compounds.
Cyanide of mercury
„ zinc and
potassium
Ferrocyanide of po-
tassium . . .
Ferricyanide of po-
tassium
Chloride of carbon
Napthaline . .
Cerotic acid . . .
Palmitate of melis-
syle . .
Cane-sugar .
Mannite . . . ,
Succinic acid . .
Tartaric acid . .
Racemic acid .
Formiate of baryta
Oxalate of potass
HgG9 N„
Fe4K4G6N6 + 3H20 .
C2C16 . .
:}
£6h14o6 .
€4H6G2 .
€4H6G6 .
€2H6G6+H20
G2 H9 Ba 04 .
c2k;o4+h2o
(Compare § 89).
. .
Atomic
Atomic
Specific
Specific
weight.
heat.
heat.
heat.
Calculated. Calculated.
Observed.
252
22-8
0-091
0-100
Kp.
247-4
52-0
0-210
©
to
i—1
Kp.
329-3
74-8
0-227
0-233
Kp.
422-4
107-0
0-253
0-280
Kp.
237
42-0
0-177
0-178
Kp.
128
36-4
0-284
0-310
A.
410
108-8
0-441 |
676
302-4
0-447 J
0-429
Pr.
342
116-2
0-340
0-301
Kp.
182
67-0
0-368
0-324
Kp.
118
37-0
0-314
0*313
Kp.
150
45-0
0-300
0-288
Kp.
168
53-6
0-319
0-319
Kp.
227
30-6
0-135
0-143
Kp.
184-2
41-0
0-223
0-236
Kp.
198
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Atomic
weight.
Atomic Specific
heat. heat.
Calculated. Calculated.
Specific .
heat.
Observed.
Quadroxalateofpot- ]
ass . . . .
fG*H8
K08 + 2 HO . .
254-1
69-7
0-274
0-283
Kp.
)
Bitartrate of potass
KOe . . . .
188-1
49-1
0-261
0-257
Kp.
Seignette salt .
O, h.
NaK0fi + 4H9O
282-1
87-6
0-311
0-328
Kp.
Bimalate of potass .
C8 H10 Ga G10+8H2O.
450
152-6
0-339
0-338
Kp.
111. The preceding synopsis shows, for the great majority of substances contained
in it, an adequate agreement between the observed specific heats and those calculated
on such simple assumptions. In estimating the differences, the extent must be remem-
bered to which various observers differ for the same substance. It must be considered
that the present better determinations of the specific heat, even those made by the
same experimenter, for substances where it may be expected that Neumann’s law applies,
do not exactly agree with it, not more nearly than within or ^ of the value ; and
that for those elements which are considered here as obeying Dulong and Petit's law,
even greater deviations occur between the numbers found experimentally and those to be
expected on the assumption of the universal validity of this law. (These deviations, i. e.
the differences between the atomic heats found for these elements, are seen from § 82.)
The extent to which the experimentally determined specific heats deviate from such a law,
Neumann’s for instance, in bodies for which calculation takes it as applying, gives of course
the means of judging what differences may occur between the observed and calculated
numbers without invalidating the admissibility of the calculation attempted. And it is
as much a matter of course that, in those bodies in which a marked deviation from
Neumann’s law has been already mentioned (compare § 95), a greater difference is found
in the present synopsis between calculation and observation.
I consider the agreement between calculation and observation, as shown in the synopsis
§ 103 to 110, as in general sufficient for a first attempt of that kind. But it need
scarcely be mentioned that I by no means consider the calculated as more accurate than
the observed numbers, or among several numbers consider that the most accurate which
is nearest the calculated ; for that, the bases of calculation are much too uncertain.
The list of atomic heats given at the commencement of § 103 is scarcely much more
accurate than were the first tables of atomic weights; but just as the latter have expe-
rienced conlinual improvements, and thus what was at first only an approximate agree-
ment between the calculated and observed composition of bodies has been brought
within considerably narrower limits, and apparent exceptions been explained, so, in like
manner, will this be the case for ascertaining what atomic heats are to be assigned to
the elements, and how the atomic heats of compounds may be deduced therefrom. This
much, however, may even now be said, that while formerly for many solid substances a
statement of the specific heat could in no way be controlled, a concealed source of error
for the determination of this property was not indicated, and an error which materially
altered the number for this property could not be recognized, at present, even if only
roughly, spell a control is possible. Compare § 77.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
199
PART VI.— CONSIDERATIONS ON THE NATURE OF THE CHEMICAL ELEMENTS.
112. The proof given in the preceding that Dulong and Petit’s law is not univer-
sally valid, justifies certain conclusions, in reference to the nature of the so-called
chemical elements, which may here be developed.
What bodies are to be regarded as chemical elements X Does the mere fact of inde-
composability determine this X or may a body be indecomposable in point of fact and yet
from reasons of analogy be regarded not as an element but as a compound X The history
of chemistry furnishes numerous examples of cases in which sometimes one and some-
times another mode of view led to results which at present are regarded as accurate.
The earths were in 1789 indecomposable in point of fact, when Lavoisier expressed the
opinion that they were compounds, oxides of unknown metals. Lavoisier’s argumenta-
tion was based on the fact that the earths enter as bases into salts, and that it was to be
assumed in regard to all salts, that they contained an oxygen acid and an oxygen base.
But the view, founded on the same basis, that common salt contains oxygen, and the
subsequent view that what is now called chlorine contained a further quantity of
oxygen besides the elements of an oxygen acid, did not find an equally permanent recog-
nition. On the basis of the actual indecomposability of chlorine, Davy maintained
from about 1810 its elementary character; and this view has become general, especially
since Berzelius, after a long struggle against it, adopted it, more I think because he
was outvoted than because he was convinced.
Almost all chemists of the present time consider chlorine, and in conformity therewith
bromine and iodine, as elementary bodies ; but the persistence is known with which
Schonbein attacks this view, and adheres to the opinion that these bodies are oxygen
compounds, peroxides of unknown elements. Is there anything which enables us to decide
with more certainty on the elementary nature of chlorine and the analogous bodies than
has hitherto been the easel
No one can maintain that the bodies which chemists regard as elements are abso-
lutely simple substances. The possibility must be confessed that they may be decomposed
into still simpler bodies ; how far a body is to be regarded as an element is so far relative,
that it depends on the development of the means of decomposition which practical che-
mistry has at its disposal, and on the trustworthiness of the conclusions which theoretical
chemistry can deduce. A discussion as to whether chlorine or iodine is an elementary
body can only be taken in the sense whether chlorine is as simple a body as oxygen or
manganese, or nitrogen ; or whether it is a compound body, as peroxide of manganese or
peroxide of hydrogen for example.
If Dulong and Petit’s law were universally valid, it would not merely indicate for
chemical elements a relation between the atomic weight and the specific heat in the
solid state, but it could be used as a test for the elementary nature of a body whose
atomic weight is known. That iodine, from a direct determination of specific heat, and
chlorine by an indirect determination had atomic heats agreeing with Dulong and
mdccclxv. 2 E
200
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
Petit’s law, would be a proof that iodine and chlorine, if compounds at all, are not more
so than other so-called elements for which this law is regarded as valid.
According to Neumann’s law, compounds of analogous atomic composition have
approximately the same atomic heats. In general, bodies, whose atom consists of a
greater number of indecomposable atoms, or is of more complicated composition, have
greater atomic heats. In these compounds, more especially those whose elements all
follow Dulong and Petit’s law, magnitude of atomic heat is exactly a measure of the com-
plexity or of the degree of composition (compare § 93). If Dulong and Petit’s law were
valid, it could be concluded with great positiveness that the so-called elements, if they are
compounds of unknown and simpler substances, are compounds of the same order. It
would be a remarkable result that the act of chemical decomposition had everywhere
found its limit at such bodies as those which, if compound at all, have with every
difference of chemical deportment the same degree of composition. Imagine the
simplest bodies, probably as yet unknown to us, the true chemical elements, forming
a horizontal spreading layer, and piled above them, the simpler and then the more
complicated compounds ; the universal validity of Dulong and Petit’s law would include
the proof, that all elements at present assumed by chemists lay in the same layer, and
that chemistry in recognizing hydrogen, oxygen, sulphur, chlorine, and the different
metals as indecomposable bodies, had penetrated to the same depth in that field of
inquiry, and had found at the same depth the limit to its penetration.
This result I formerly propounded * when I still believed in the validity of Dulong
and Petit’s law. But with the proof that this law is not universally true, the conclu-
sion to which this result leads loses its justification. Starting now from the elements
recognized in chemistry, we must rather admit that the magnitude of the atomic heat
of a body depends not only on the number of elementary atoms contained in one atom
of it, or on the complexity of the composition, but also on the atomic heat of the
elementary atoms entering into its composition ; it appears now possible that a decom-
posable body may have the same atomic heat as an indecomposable one.
To assume in chlorine the presence of oxygen, and to consider it as analogous to per.
oxide of manganese, or in general to the peroxide of a biatomic element f, is less in
accordance with what is at present considered true in chemistry, than to consider it as
the peroxide of a monoequivalent element, analogous to peroxide of hydrogen. It is
remarkable that peroxide of hydrogen, in the solid state or in solid compounds, must
have almost as great an atomic heat (for H0 2-3+4 = 6-3) as those elements which obey
Dulong and Petit’s law, and especially as iodine, bromine, and chlorine, according to
the direct and to the indirect determination of their atomic heat ; the same must be the
case for the analogous peroxides of such still unknown elements as have an atomic heat
* “ On the Difference of Matter from the Empirical point of view,” an Academical Discourse. Giessen, i860.
f I will not omit to mention that equivalent weights of iodine and peroxide of manganese have almost equal
capacity for heat. As regards oxidizing action, 127 of iodine corresponds to 43-5 peroxide of manganese;
Regnault found the specific heat of the former =0-0541; I found that of the latter =0-159;
127 x 0-0541 =6-87; 43-5 x 0-159=6-92.
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
201
as great as that of hydrogen. As far as may be judged from its specific heat, chlorine
may be such a peroxide ; but this consideration shows no necessity for assuming that it
actually is so.
In a great number of cases the atomic heat of compounds gives more or less accurately a
measure for the degree of complexity of their composition*. And this is the case also with
such compounds as are comparable in their chemical deportment to undecomposed bodies.
If cyanogen or ammonium had not been decomposed, or could not be so with the means
at present offered by chemistry, the greater atomic heats of their compounds, compared
with those of analogous chlorine or potassium compounds (compare § 96), and of cyano-
gen and ammonium as compared with chlorine and potassium, would indicate the more
complex nature of those so-called compound radicals. The conclusion appears admis-
sible that for the so-called elements the directly or indirectly ascertained atomic heats
are a measure for the complexity of their composition. Carbon and hydrogen, for
example, if not themselves simple bodies, are more so than silicium or oxygen ; and still
more complex compounds are the elements which are now considered as following Dulong
and Petit’s law; with the restriction, however, that for these also the atomic heats
may be more accurately determined and differences proved in them which justify similar
conclusions f. One might be tempted, by comparing atomic heats, to form an idea how
the more complex of the present indecomposable bodies might be composed of more
simple ones, just as such a comparison has been shown to be possible for chlorine ; but
it is at once seen that to carry out such an attempt the atomic heats of the elements,
especially those which can only be indirectly determined, are not settled with adequate
certainty.
It may appear surprising, or even improbable, that so-called elements which can
replace each other in compounds, as, for instance, hydrogen and the metals, or which
enter into compounds as isomorphous constituents, like silicium and tin, should possess
unequal atomic heats and unequal complexity of composition. But this is not more
surprising than that indecomposable bodies, and those which can be proved to be com-
pound, as, for example, hydrogen and hyponitric acid, or potassium and ammonium,
should replace one another, preserving the chemical character of the compounds, and
even be contained as corresponding constituents in isomorphous compounds.
I have here expressed suppositions in reference to the nature of the so-called elements
which appear to me based on trustworthy conclusions from well-proved principles. It is
* The differences in the atomic heats of the elements are of course most distinctly seen in their free state,
but in their analogous compounds these differences are the less prominent the more complex the compounds,
that is, the greater the number of atoms of the same kind and the same atomic heat which are united to those
elementary atoms whose atomic heat is assumed to he unequal. The difference in the atomic heats of G and As,
for instance (1*8 and 6-4), is relatively far greater than for Ga <3 G3 and K As03 (20-2 and 24-8).
f It is possible, for example, that certain indecomposable bodies which only approximately obey Dulong and
Petit’s law, are analogous compounds of simpler substances of essentially different atomic heat : the approximate
agreement of the atomic heats of such indecomposable bodies would then depend on a similar reason to that for
the atomic heats of Ga € 03 and K As 03. Compare the previous note.
202
PROFESSOR KOPP ON THE SPECIFIC HEAT OF SOLID BODIES.
in the nature of the case that the certain basis of fact and of what can be empirically de-
monstrated must be left. It must also not be forgotten that these conclusions only allow
something to be supposed as to which of the present indecomposable bodies are more
complex and which of simpler composition, and nothing as to the question what sim-
pler substances may be contained in the more complex ones. The consideration of the
atomic heats may say something as to the structure of a compound atom, but in general
gives no clue as to the qualitative nature of the simpler substances used in the construc-
tion of the more complex atoms. But even if these suppositions are not free from un-
certainty and imperfection, they appear worthy of attention in a subject which, for
science, is still so much in darkness, as is the nature of the indecomposable bodies.
Fk ib. Tnms. MDCCCLXV . PteXX.
fflMnfflii
IBilillflllflMiiiiii
—
Kg. 8.
Bg.7.
[ 203 ]
IV. On the Composition of Sea-water in the different parts of the Ocean. By Georg
Forchhammer, Professor at the University, and Director of the Polytechnic Institu-
tion at Copenhagen. Communicated by the President.
Received July 28, — Read November 17, 1864.
In the year 1843 a friend of mine, Mr. Ennis of Falmouth, sent me some bottles of sea-
water from the Mediterranean, which I subjected to a chemical examination, a work
which induced me to collect what other chemists had determined about the constitution
of the water of the great Ocean. This labour convinced me that our knowledge of the
composition of sea-water was very deficient, and that we knew very little about the
differences in composition which occur in different parts of the sea.
I entered into this labour more as a geologist than as a chemist, wishing principally
to find facts which could serve as a basis for the explanation of those effects that have
taken place at the formation of those voluminous beds which once were deposited at
the bottom of the ocean. I thought that it was absolutely necessary to know with
precision the composition of the water of the present ocean, in order to form an opinion
about the action of that ocean from which the mountain limestone, the oolite and the
chalk with its flint have been deposited, in the same way as it has been of the most
material influence upon science to know the chemical actions of the present volcanos,
in order to determine the causes which have acted in forming the older plutonic and
many of the metamorphic rocks. Thus I determined to undertake a series of investi-
gations upon the composition of the water of the ocean, and of its large inlets and bays,
and ever since that time I have assiduously collected and analyzed water from the dif-
ferent parts of the sea. It is evident that it was impossible to collect this material in a
short time, and without the assistance of many friends of science, and I most gratefully
acknowledge how much I am indebted to many distinguished officers of the Danish and
British Navy, as well as to many private men, who were all willing to undertake the
trouble carefully to collect samples of sea-water from different parts of the ocean, both
from the surface and from different depths. I shall afterwards, when giving the parti-
cular analyses, find an opportunity to mention the name of each of those to whom I am
indebted for my material.
While I was thus occupied for a space of about twenty years, another series of expe-
riments closely allied to my work was commenced in England, and has partly been
published under the able and scientific superintendence of Rear-Admiral FitzRoy.
This most important series of observations regards the specific gravity of sea- water from
the most different parts of the globe ; it comprehends a much more numerous series
mdccclxv. 2 F
204
PROFESSOR FORCHHAMMER ON THE COMPOSITION
than my observations, but I trust that it will not make my work superfluous, but that
both these investigations will supplement each other. By the kindness of Admiral
FitzRoy I am able to compare the instruments which are used by the British Navy with
my chemical analyses, and thus to obtain a comparison between both series.
I have at different times found an opportunity to publish several parts of my obser-
vations, and in 1859 I collected what had been done up to that time in an academical
treatise in the Danish language*. Since that time I have obtained numerous samples
of sea-water, principally from places which my previous examination had not reached.
In this new form, and greatly augmented by new facts, I permit myself to lay it before
the illustrious scientific society of a nation to whose navigators I owe so great a part of
the material for my inquiries. This part contains an enumeration of the elements which
hitherto have been ascertained to exist in the water of the ocean, and an explanation
of the methods used to show their presence and to determine their quantity. It con-
tains a determination as complete as possible of the distribution of the saline substances
at the surface of the different parts of the sea, and in the different depths at the same
place.
On the Elements which occur in the Water of the Ocean.
The elements which occur in greatest quantity in sea-water have been long known,
and chlorine, sulphuric acid, soda, magnesia, and lime have for more than a century
past been considered as its essential parts. In our century iodine, bromine, potash,
silica, phosphoric acid, and iron have been discovered in sea-water, and the latest
inquiries, my own included, have brought the number of elements occurring in sea-water
up to twenty-seven.
Next to direct analyses of sea-water, the analysis of sea-weeds, and of animals living
in the sea, offers us precious means of determining those elements which occur in so
small a quantity in sea-water, that it hitherto has been impossible to ascertain their
presence in the water by chemical tests. It is now well known that the organic beings
collect substances which are necessary for their existence, and thus offer the means to
the chemist of ascertaining that these Substances were present in the medium in which
the organisms lived, and from which they collected their food. As to the plants of the
sea, the whole fucoid tribe derive the substances of which they consist from the sur-
rounding sea-water and from the air with which they are in contact, but not from the
soil on the bottom of the sea, since that part of them which generally is called their root
is no root at all, and is not qualified to extract food from the soil and stones to which
it adheres. Even those marine plants which do not belong to the fucoid tribe, as, for
instance, the Zostera marina , and which have a real root, that may extract food from
the soil, will most probably extract the great quantity of mineral elements which they
contain mostly from the surrounding sea-water. As to the animals that live in the sea,
they derive their substance either from the sea-water itself, or from plants that are
* Om Soevandets bestanddele og deras Fordeling : Hayet. af G. Forchhammek, Professor ved Kjobenhavns
TJniyersitet.
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
205
nourished by sea-water, or from other animals that live upon sea-weeds, thus deriving
their whole mineral substance either directly or indirectly from the sea. I have availed
myself of the means which the organisms of the sea furnish, to determine a great
number of elements that thus must exist in solution in sea-water.
As to this great number of elements contained in the sea-water, we might ask one
question, which is of great importance for the history of the earth, viz. how all these
elements got into the sea, whether they were in the original sea, or subsequently got
into the sea, where they are now slowly accumulating. When we consider that the sea
constantly loses a great quantity of pure water by evaporation, and that a large part of
this water falls on the land, dissolves a number of substances from it, and carries them
at last into the sea, where they constantly would increase in quantity if it were not for
its organisms which deprive it again of them, we may well suppose that these two
effects, of which the one acts to increase, and the other to diminish the quantity of
mineral substances in sea-water, are pretty equal, and leave the sea unchanged. I will,
however, not dwell upon these mutual chemical decompositions and combinations,
which, partly depending upon organic life, partly upon inorganic mechanical and che-
mical forces, play such a great part in the changes of the earth, but I hope at some
future time to find leisure to publish my investigations in this branch of the history of
the earth.
The elements which hitherto have been found in sea-water are, —
1. Oxygen. — Besides that oxygen which is a constituent part of water, and other
compounds that occur in the sea, such as the sulphates, phosphates, carbonates, and
silicates, it occurs in a free uncombined state, absorbed by the water itself. It plays a
very material part in the small but constant changes which take place in the sea- water,
and whose general effects are that the organic substances dissolved in it are changed
into carbonic acid and water. This effect takes place principally near the surface, and
decreases with increasing depth ; and water from the deeper parts of the sea is able to
destroy the colour of a greater quantity of the hypermanganate of potash than that from
the surface, which again shows that there is more organic matter undestroyed in the
deep sea.
2. Hydrogen. — Besides the hydrogen which belongs to the composition of water, it
occurs in the organic substances and in the ammonia which are dissolved in sea-water.
3. Chlorine. — Next to the elements of water chlorine is the element which occurs
in greatest quantity in sea-water, and has from the earliest times been recognized as
such.
4. Bromine has been long known as an essential part of the sea, easily recognized in
the residue from the evaporation of sea-water after the crystallization of the greater part
of the chloride of sodium.
5. Iodine. — This substance is well known to have been the first element in sea-water
discovered not directly, but by the analysis of the ashes of fucoidal plants, which by
organic power had collected and concentrated it from sea-water.
6. Fluorine. — Dana long ago showed that fluorine occurs in the lime of corals, where
2 f 2
206
PROFESSOR FORCHHAMMER ON THE COMPOSITION
its presence may be ascertained with great facility. To prove directly its existence in
sea-water, I evaporated 100 lbs. of it taken in the Sound near Copenhagen, and when
it was so much condensed that the salt began to crystallize, I precipitated the whole
by an excess of ammonia, washed the precipitate, and dissolved in muriatic acid. It
was now again precipitated by ammonia, and the precipitate boiled with a solution of
muriate of ammonia. The washed precipitate weighed now 3T04 English grains, and
was divided into two parts, of which one was heated in a small platinum crucible with
sulphuric acid. The vapours etched glass. The other part was distilled in a bent glass
tube with sulphuric acid, and the vapour condensed in a solution of ammonia. The
vapours etched the glass tube, and when the ammoniacal liquor was evaporated and the
salt dissolved, silica remained. With much greater facility the fluorine was shown in
the stony matter deposited at the bottom of the boilers of the Transatlantic steamers, of
which I owe samples to the late Dr. G. Wilson of Edinburgh, who likewise discovered
fluorine in sea-water.
7. Sulphur. — This element occurs in considerable quantity in sea-water combined with
oxygen as sulphuric acid, forming salts with baryta, strontia, lime, and magnesia. In
pure sea-water, or in such sea-water as only contains a very small quantity of organic
matter, no decomposition of the sulphates takes place, and I have kept sea-water for
many years in well-corked bottles without the least alteration. Near the shores and at
the mouth of great rivers, where considerable quantities of organic matter are washed
into the sea, it is easily decomposed, particularly if it is kept in bottles. This decompo-
sition shows itself always by the production of sulphuretted hydrogen. Water from the
polar regions is very subject to decomposition, probably on account of a greater quan-
tity of organic matter than in water from lower latitudes. It is, however, very difficult
to assign all the different causes which may produce decomposition of sea-water. All
the water which was brought by the Swedish Spitzbergen Expedition in bottles from
the polar sea was decomposed, and emitted sulphuretted hydrogen when the bottles
were opened, while all the water brought from the same sea by the same Expedition
in tubes of glass, hermetically closed by melting, was undecomposed. Hyperman-
ganate of potash is the best test for the sulphuretted hydrogen of such water, its colour
is instantaneously destroyed by the water, and sulphuric acid is formed again. The
quantity of sulphuretted hydrogen formed in such water differs greatly, and depends,
at least partly, upon the quantity of organic matter contained in it. Water from the
Mediterranean is very subject to this kind of decomposition ; but the greatest quantity
of sulphuretted hydrogen which I have met with in any sample was found in water
which I owe to Admiral Washington, and which had been taken by Captain Peevost
of the ‘ Satellite’, under 35° 46' S. lat. and 52° 57' W. long., off the east coast of South
America, and not very far from the mouth of the Rio de la Plata ; 3000 grains of this
water destroyed the colour of 455 drops of a solution of hypermanganate of potash, of
which the same quantity of ordinary sea-water only bleaches four to six drops*.
* This test has only a relative value in comparing different kinds of water, the quantity of oxygen required
for complete oxidation being proportional to the quantity of hypermanganate destroyed.
or SEA- WATER IN THE DIFFERENT PARTS OF THE OCEAN.
207
In this kind of decomposition, where sulphuretted hydrogen is formed, the organic
matter is changed into carbonic acid and water, while the oxygen which this change
requires is taken from the sulphates, and the sulphuret thus formed takes its oxygen
again from the hypermanganate. Thus the result of the series of decompositions is the
revival of the same sulphate with which it began, and the formation of carbonic acid
and water from the organic matter which was present. In the second case, where the
hypermanganate directly oxidizes the organic matter, the same quantity of oxygen must
be used, and the same products are obtained. In both cases the oxygen is ultimately
derived from the hypermanganate. This reasoning supposes that no oxygen from the
atmosphere is absorbed, and no sulphuretted hydrogen has escaped during the opera-
tions. The absorption of oxygen is prevented by the cork of the bottle, but when it is
opened some sulphuretted hydrogen certainly will escape, and we may conclude that in
the cases where sulphuretted hydrogen is formed, there has been a little more organic
matter than the hypermanganate indicates.
This fermentation of the sea-water occasions of course a loss of sulphuric acid, and
makes the analysis in some degree inaccurate. The greatest loss of sulphuric acid which
I have observed was in the case of the water from the 4 Satellite ’ above mentioned,
where the proportion to chlorine was found to be 9T3: 100, while the mean proportion
is 1T94: 100, thus about one-seventh of the sulphuric acid was decomposed. It is very
probable that this great quantity of organic matter is owing to the water of the Eio de
la Plata, because the water contained only 17*721 chlorine, while the mean number for
that region is 19*376, which seems to prove a considerable admixture of river-water. I
may here also mention a curious instance where no decomposition had taken place,
although the circumstances seemed to be very favourable for it. The sample had been
taken by the late Sir James Koss in 1841, at 77° 32' S. lat., in the neighbourhood of the
great ice-barrier, and it was marked “ Sea-water containing animalculae.” It was very
muddy when I opened the bottle, but had not the least smell of sulphuretted hydro-
gen. Tested without being filtered, 1000 grains bleached 180 drops of the hyperman-
ganate ; when filtered the same quantity bleached 39 drops. It contained thus a great
quantity of organic matter. The quantity of chlorine was 15*748, which proves that
it was much diluted, probably by the melted ice from the barrier ; the proportion of
sulphuric acid to chlorine was 11*65 : 100, which approaches pretty near to the normal
proportion. It had been about twenty years in the bottle when I analyzed it, and the
cork was sound. It is difficult to conceive why this water had not suffered any decom-
position.
8. Phosphorus. — This element, in combination with oxygen, is a never failing part of
sea-water, which remains as phosphate of lime when the water is evaporated to dryness
and the salts remaining dissolved in boiling water. The small quantity of insoluble
matter which remains consists of phosphate of lime, sulphates of baryta and of strontia,
fluoride of calcium, carbonate of lime, and silica. When this mixed substance is heated
with muriatic acid, filtered, and tested with molybdate of ammonia, phosphoric acid will
208
PROFESSOR FORCHHAMMER ON THE COMPOSITION
always be found ; or when the insoluble remainder from evaporation is heated in a glass
tube with potassium, it will, when breathed upon, emit the smell of phosphuretted
hydrogen.
9. Nitrogen occurs in sea-water combined with hydrogen as ammonia, and its presence
may be shown by mixing sea-water with a solution of baryta, and distilling the mixture
in a glass retort. In the distilled portion ammonia may be shown by adding some drops
of nitrate of protoxide of mercury, which will form grey clouds, or by muriatic acid and
chloride of platinum, which, when carefully evaporated, will leave the well-known yellow
salt insoluble in alcohol. It can hardly be doubted that this ammonia is partly formed
by the living animals of the sea, which exhale ammonia, and partly by the putrefaction
of their dead bodies. We might ask why we find so small a quantity of ammonia, the
causes for its formation being so general ; but it is well known that plants will absorb
it, and that the circulation of nitrogen in the sea is between sea-water, plants, and ani-
mals, as it is on the dry land between soil, plants, and animals.
10. Carbon occurs always in the water of the sea, partly as free carbonic acid, partly,
but in very small quantities, as carbonate of lime, partly in combination with oxygen,
hydrogen, and nitrogen as organic matter, derived from the destruction of the numerous
organic beings that live in the sea. It is by the oxidation of these substances that
the sulphates of sea-water are decomposed, and that the hypermanganate of potash is
bleached when boiled with sea-water ; and it is owing to these substances that all sea-
water disoxidizes the peroxide of iron either to protoxide or to sulphuret, and that all
ferruginous clay or sand deposited in deep sea has a dark colour.
11. Silicium . — Silica is found in the insoluble remainder from the evaporation of sea-
water when the salts are dissolved in water. It can be separated from the phosphates
and fluorides by dissolving in weak muriatic acid, when it remains undissolved along with
small quantities of sulphate of baryta and strontia. In this state it is easily recognized
by the blowpipe. In the Sponges it is collected in great quantity ; and when the large
cyathiform sponge from Singapore is calcined, it leaves a skeleton which retains the
original form and size of the sponge, and consists almost entirely of silica, the large pores
of it being lined with oxide of iron, which evidently has belonged to some part of the
animal itself. It is found also in other animals of the sea, and it occurs in the ashes of
sea-weeds of the fucoid family, though it is not yet ascertained whether it belongs to
the fucus itself, or to the infusoria which usually cover its surface.
12. Boron. — I have long tried to find boracic acid in sea-water, but for a long time
all my endeavours were vain. Notwithstanding I felt convinced that it must be there,
since both boracic acid and borates are not very rare, and a great part of its salts
with lime and magnesia are more or less soluble in water. Thus I thought that water
from the land must have carried boracic acid into the sea, where it still must be accu-
mulating, since we do not know any combination by which it could be separated again
from the water. An additional proof of the correctness of this idea I found in the
occurrence of Stassfurthite (mostly consisting of borate of magnesia), together with all
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
209
other salts that occur in sea-water, in the beds of rock-salt at Stassfurth in Germany.
The lower part of this bed of rock-salt, which by a boring was not penetrated through
at a depth of 800 feet, consists of pure chloride of sodium. Upon this rest the other
salts of sea-water, consisting of magnesia, lime, and potash combined with muriatic and
sulphuric acids in numerous combinations, among which we also find the Stassfurthite
(borate of magnesia with chloride of magnesium). Boracite, a similar combination of
boracic acid, occurs at Luneburg and at Segeberg, associated with gypsum and chloride
of sodium, which latter at Luneburg forms a spring of saturated brine, and at Segeberg
occurs in separate crystals imbedded in the gypsum.
I thought I might be able to form a borate insoluble in water, and with such charac-
teristic properties that it might be possible to determine the boracic acid in it. It is
well known that Heintz, by melting chloride of magnesium, chloride of sodium, mag-
nesia, and boracic acid, obtained octohedral crystals, which were boracite, and another
set of crystals, of hemiprismatic form, which also contained boracic acid and magnesia.
The crystals were microscopic, but could easily be recognized by their different form of
crystallization. To make myself acquainted with these different artificial combinations,
I melted borax, common salt, and sulphate of magnesia in a crucible, allowed it to cool
slowly, and dissolved it in water. There remained a heavy crystalline powder, which
under the microscope proved to consist of six-sided hemiprismatic prisms, containing
both magnesia and boracic acid. I could not discover any octohedral crystal, and no
boracite seemed to have been formed. In another experiment I fused common salt,
magnesia, and borax; after solution I obtained the same hemiprismatic crystals, but
no octohedrons ; and felt now convinced that I hardly should obtain boracite by fusing
salt of sea-water, but that I might obtain the hemiprismatic borate if sea-water con-
tained boracic acid.
The experiment was made in the following way : — I evaporated 6 lbs. of sea-water
taken from the Sound near Copenhagen, transferred the salt into a perfectly clean
platinum crucible, which was placed upon magnesia in a common Hessian crucible,
exposed it to a white heat, and cooled slowly. After solution of the salt, the powder
remaining was placed under the microscope, where it was found to consist almost
entirely of hemiprismatic crystals which frequently formed twins* and by their whole
exterior showed themselves to be essentially different from the hemiprismatic borate.
Many of them were corroded at the sides and ends, as if they had partly been dissolved.
I supposed them to be gypsum, which of course must be formed by the evaporation of
sea-water ; and although the gypsum by melting would be changed into anhydrite, they
afterwards, during washing with water, would again form a hydrate. I thought even
several times to have seen square prisms (anhydrite'?) change into the hemiprismatic
form under my observation in the microscope, and get oblique cracks like one cleavage
of gypsum. The powder was again washed with hot water, and the solution was
found to contain both sulphuric acid and lime. When the wash-water contained
only traces of sulphuric acid, the powder, greatly diminished in quantity, was again
210
PROFESSOR FORCHHAMMER ON THE COMPOSITION
observed under the microscope, and showed very few half-dissolved prisms of gypsum,
but numerous very small octohedrons, which had been hidden by the gypsum. Besides
these octohedrons, some hemiprismatic crystals were found, precisely similar to those
which I formerly had obtained when forming a borate of magnesia. The powder con-
tained, further, some prisms which were striated parallel to the axis, and had a face per-
pendicular to this axis ; they resembled precisely the crystals which I several years ago
described as artificial apatite, and which were obtained by fusing calcined bones with
chloride of sodium ; and they were in fact apatite, formed of the phosphoric acid,
fluorine, chlorine, and lime of the sea-water. Of the powder in question, which essen-
tially consisted of octohedrons, I dissolved 7T84 grains in nitric acid, which left 0T60
grain of a reddish powder consisting mostly of oxide of iron, but showing also under
the microscope hemiprismatic crystals like the borate of magnesia. The nitric solution
gave with ammonia a precipitate which weighed 0*633, and contained phosphoric acid.
At last the remaining solution gave with phosphate of soda and an excess of ammonia
16’667 ignited phosphate of magnesia=6‘074 pure magnesia. The sum of all these
substances thus determined was 6‘867, so that only a quantity amounting to 0‘317 grain
which was wanting could be boracic acid.
It was thus clear that the octohedrons analyzed could not be boracite, and there could
hardly be any doubt but that the substance was essentially pure magnesia, mixed with
small quantities of oxide of iron, phosphate of lime, and other substances which were still
to be determined. Pure magnesia occurs among the Vesuvian minerals crystallized in
regular octohedrons, and has obtained the name of Periclase. In this case the periclase
was formed by the decomposition of the hydrate of chloride of magnesium contained in
the salt of sea-water, and decomposed in the melting heat. As a further proof of its
nature as pure magnesia, it may be mentioned that, when boiled with a solution of sal-
ammoniac, it was dissolved with a strong smell of ammonia. The solution contained
magnesia, and nothing else besides salts of ammonia could be discovered.
When the octohedral crystals were removed by boiling with a solution of sal-ammo-
niac, the remaining powder contained only hemiprismatic prisms of the supposed borate
of magnesia, crystals of apatite, and very acute six-sided pyramids, which in their form
had some similarity to crystals of sapphire, and a considerable quantity of amorphous
red oxide of iron, probably mixed with silica. A portion of this powder was moistened
with sulphuric acid, and during twenty-four hours left to spontaneous evaporation. I
could now observe crystals of sulphate of magnesia and needles of sulphate of lime.
The substance, nearly dry, was mixed with diluted alcohol, which, when inflamed, showed
the green margin of the flame characteristic of boracic acid, and gave a brown colour to
curcuma paper, although the solution was acid. It is thus proved that this salt con-
tained boracic acid, which in this case could only be derived from sea-water. When
this powder was boiled with muriatic acid, apatite, borate of magnesia, and silicate of
peroxide of iron were dissolved, and a very small quantity of the six-sided pyramids
remained, which resisted the action of acids, but were made soluble by fusing with
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
211
carbonate of soda. When the soda was washed away, the remaining substance dissolved
in muriatic acid, and it could now be proved that alumina was present. The quantity
of these six-sided pyramids obtained from 6 lbs. of sea-water was, however, so small,
that no experiments could be made to ascertain whether it contained other substances
besides alumina.
I have been somewhat more explicit in relating my experiments to ascertain the exist-
ence of boracic acid and alumina in sea-water, partly because I found it very difficult to
find unequivocal proofs of their presence, and partly because it interested me highly to
find how useful the microscope may be in inorganic analysis, when used in combination
with chemical tests.
When I had convinced myself that boracic acid occurred in sea-water, it appeared to me
in the highest degree probable that the organisms of the sea would collect it, and that it
might be found in their ashes. I was so fortunate as to begin my experiments with a
plant that contained it in a rather large quantity, viz. the Zoster a marina. The plant
was collected in the month of December, at the sea-shore near Copenhagen, dried, and
burnt. The ashes were washed with water, and the solution, which contained mostly
chloride of potassium and sulphate of potash, contained also a small quantity of boracic
acid, probably combined with soda. The insoluble part of the ashes was moistened with
sulphuric acid until it had a sour taste, evaporated in a moderate heat to dryness, and
washed with water. When this solution was mixed with strong alcohol and filtered, it
burned with a green flame, and gave to curcuma paper a brown, and to litmus paper
a red colour. To separate the boracic acid from the other substances I chose super-
heated steam, a method to which I was led by a consideration of the way in which
boracic acid reaches the lagoons of Tuscany. It is well known that this acid comes
with steam from the interior of the earth, and is condensed when escaping from the
fumaroles. An experiment in which I mixed dry borax with sulphuric acid, and exposed
it to the action of superheated steam at 300° to 400° Centigrade, volatilized not only
boracic acid in form of a solution, but gave even the well-known scales of its hydrate.
The experiment with the distillation of the ashes of Zostera marina with sulphuric acid
and superheated steam succeeded completely. The water contained boracic acid, which
by a slow evaporation was obtained in crystalline scales ; and another portion of it was
converted into borax, which was obtained in its regular form. Even Fucus vesiculosus
contains the same acid, but in a much smaller quantity.
13. Silver. — Malaguti first showed that silver occurs in the organisms of the sea; I
have subsequently proved it to exist in a coral, a Pocillojoora, and several chemists have
since tried to prove that silver is precipitated by the galvanic current between the
copper coating of a vessel and sea-water. If the last determination is confirmed, the
existence of silver in sea-water is proved by direct experiment. From the Pocillojpora
alcicornis I have separated it in the following manner : — I dissolved the coral in muriatic
acid, precipitated the solution by hydrosulphate of ammonia, and dissolved the preci-
pitate, which consisted of sulphurets, of phosphate of lime, and fluoride of calcium, in
mdccclxv. 2 G
212
PROFESSOR FORCHHAMMER ON THE COMPOSITION
very weak cold muriatic acid, which left the sulphurets of silver, lead, and copper pro-
bably mixed with those of cobalt and nickel. These sulphurets were separated from
the solution, evaporated to dryness with a little nitric acid, to which were added a few
drops of muriatic acid, and dissolved in water, which leaves sulphate of lead and chlo-
ride of silver undissolved. When the filter which contained the latter substances is
burnt, the silver is reduced to metal ; a solution of pure soda will dissolve the sulphate
of lead and leave the silver, which, when dissolved in nitric acid, can be tested with
muriatic acid. I obtained from Pocillopora alcicornis about 3,000,000? or from a solid
cubic foot of the coral about half a grain of silver.
14. Copper has not been discovered in sea- water itself, but occurs so frequently in
the lime-salts of the animals of the sea, and in the ashes of the sea- weeds, that it can be
discovered with great facility by its well-known tests. In the Pocillopora I found about
six times more copper than silver, in the coral Heteropora abrotanoides about 350*000
copper, and in the yellowish-green substance which remained after the filtration of the
muddy sea-water which Sir James Ross had taken in 77° 33' S. lat., it could be shown
with great facility. Also the ash of Fucus vesiculosus contained copper.
15. Lead occurs, like copper, in the shells of the animals of the sea and in the ashes
of sea-weeds, but in greater quantity. In the Pocillopora alcicornis there was found
about eight times as much lead as silver, and in Heteropora abrotanoides about 50q00
of the coral. It occurs likewise in Fucus vesiculosus.
16. Zinc. — It has not been shown directly in sea- water, nor could I find it in the
lime-salts of shells and corals, but it occurs in considerable quantities in the ashes of sea-
weeds; 400 grains of the ashes of Zostera marina contained 0T39 oxide of zinc = 3-^00.
It occurs also in the ashes of Fucus vesiculosus.
1 7. Cobalt. — I have discovered this metal in the ashes of Zostera marina , and in the
fossil sponges of the chalk, but not in the large cyathiform sponge of the present sea
from Singapore.
18. NicJcel. — We have no such delicate test for nickel as the blowpipe is for cobalt,
but I have several times observed the well-known brown colour of the solution on pre-
cipitating the sulphurets of the ashes of sea-weed by hydrosulphate of ammonia, and I
think we are fairly entitled to suppose that these two metals occur together in sea-water
as they occur in company in the mineral kingdom.
19. Iron can be discovered directly in sea-water by evaporating it to dryness and
dissolving the salts again in water, when it remains insoluble and combined with silica.
It remains mixed with all the other combinations that are insoluble or difficultly soluble
in water, but in the solution of these residues in muriatic acid can easily be indicated by
the common prussiate of potash. It occurs in great quantity in the ashes of sea-weeds
and the lime-salts of sea animals.
20. Manganese can be determined directly in sea-water, accompanying the oxide
of iron separated from a rather large quantity of sea-water, by the application of the
well-known test for manganese before the blowpipe with carbonate of soda and nitrate
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
213
of soda or potash. In some sea-weeds it occurs in considerable quantity, particularly
in the ashes of Zostera marina when it is in full growth. This ash contains about
4 per cent, of it, enough, when muriatic acid is poured upon the ash, to cause an effer-
vescence of chlorine. Manganese is found in a much smaller quantity in the animals of
the sea.
21. Aluminium. — I have often tried to find alumina in sea-water which had been
filtered, but always without result, until at last, in my experiments to find boracic acid,
I found alumina also, as is mentioned under boron. Aluminium must thus be enume-
rated as one of the elements that occur in the water of the sea. It occurs in greater
quantity than most metals, iron, and perhaps manganese, excepted.
22. Magnesium. — This element occurs, as is well known, in large quantity in sea-
water, in about the same quantity as sulphuric acid, and only sodium and chlorine are
found in greater quantity. Sea-weeds contain it likewise in considerable quantity, and
it is a constant companion of the carbonate of lime which the shell-fishes and corals
deposit. In Serjgula jiligrana it amounts to 13-49 per cent, carbonate of magnesia. Its
average quantity is, however, only 1 per cent.
23. Calcium. — Lime occurs in sea-water in a small quantity combined with carbonic
acid, and dissolved in an excess of it ; in a greater quantity combined with phosphoric
acid, and as fluoride of calcium ; but the greatest quantity is combined with sulphuric
acid. Among all the bases which river-water carries into the sea, lime is the most fre-
quent ; and it is only owing to the organic beings of the sea, and principally to its lower
animals, that so small a quantity remains, lime being constantly separated by the organo-
chemical action of these animals.
24. Strontium. — I have discovered this element in the sea-water, and also in the
deposit of the boilers of the Transatlantic steamers. It occurs likewise in the ashes of
the fucoid plants, and specially in the Fucus vesiculosus. I shall here explain how I
have convinced myself that this plant contains both strontia and baryta. When the ash
was successively extracted, first with water, and then with muriatic acid, a rather
considerable quantity of insoluble substances remained, which was fused with carbonate
of soda, and again extracted by water containing some pure soda to dissolve the silica,
while the sulphuric acid from the sulphate of strontia and baryta had combined with
the soda of the carbonate. To remove the lime from the remainder, I dissolved it in
muriatic acid which contained a little sulphuric acid. What remained undissolved was
again fused with carbonate of soda and extracted with water. The remaining car-
bonates were now dissolved in muriatic acid, and afterwards precipitated by a solution
of sulphate of lime. The mixed sulphates of strontia and baryta were separated by
flaosilicic acid, and the salt of strontia dissolved in alcohol, which then burned with the
beautiful red colour of strontia.
25. Baryta occurs both hi sea-weeds and in sea-animals, but the ashes of sea-weeds
contain more of it than the corals and shells. It can even be determined directly in sea-
water, and in the deposits of the boilers of the Transatlantic steamers.
2 g 2
214
PROFESSOR FORCHHAMMER ON THE COMPOSITION
26. Sodium. — It is well known that sodium in combination with chlorine forms the
most important salt in sea-water; next to chlorine, oxygen, and hydrogen, sodium is the
most abundant element in sea-water.
27. Potassium is the alkaline element which, next to sodium, occurs most frequently
in sea-water, and it may easily be shown in the sea-water itself.
On the Quantitative Analysis of Sea-water.
It is evident that an analysis which should determine the quantity of every one of the
substances now enumerated would be a very laborious task, and that the number of
analyses required to ascertain the composition of sea- water in different parts of the
ocean would be a work exceeding the power of a single observer. Besides this there
is another difficulty, which makes a series of such analyses quite impossible ; 100 lbs.
of sea-water would be the least quantity that could be used, but such a quantity could
but with difficulty be procured, and could not be kept unaltered by evaporation and
fermentation. Fortunately such analyses are not required, and of the numerous
elements discovered in sea-water, only a few occur in such a quantity that their
quantitative determination can be of any consequence. It is besides a result of my
analyses of sea-water, that the differences which occur in water from different parts of
the ocean essentially regard the proportion between all salts and water, the strength
of sea-water, or, to use another expression, its salinity , and not the proportion of the
different elements of the salts invicem ; in other words, the difference in the proportion
between chlorine and water may be very variable, but the proportion between chlorine
and sulphuric acid, or lime or magnesia will be found almost invariable. The sub-
stances which, in respect of quantity, play the principal part in the constitution of sea-
water, are chlorine, sulphuric acid, soda, potash, lime, and magnesia ; those which occur
in less, but still determinable quantity are silica, phosphoric acid, carbonic acid, and
oxide of iron. All the numerous other elements occur in so small a proportion, that
they have no influence whatever on the analytical determination of the salinity of sea-
water, though, on account of the immense quantity of sea-water, they are by no means
indifferent, when we consider the chemical changes of the surface of the earth which
the ocean has occasioned, or is still producing.
In my complete quantitative analyses I have always determined the quantity of chlo-
rine, sulphuric acid, magnesia, lime, and potash. The sodium or soda is calculated
under the supposition that there were no other metalloids or acids than chlorine or
sulphuric acid, and no other bases or oxides of metals than lime, magnesia, potash, and
soda ; it was supposed, besides, that the sea-water was neutral. These suppositions are
not quite correct : of metalloids we find, besides chlorine, bromine, iodine, and fluorine ;
of acids we find, besides sulphuric acid, also carbonic, boracic, silicic, and phosphoric
acids ; and of bases we find, besides those that have been enumerated, a great number ;
but all these substances occur in very small quantities, and may be neglected. I have,
however, in most cases determined the quantity of insoluble remainder left when sea-
Or SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
215
water is evaporated to dryness, dissolved in water, and washed until all sulphate of lime
is removed. This remainder contains silica, phosphate of lime, carbonate of lime,
sulphate of baryta and strontia, oxide of iron, and probably borate of magnesia or
lime, and is in my memorandum of the analysis mentioned under one head, with the
designation Silica, &c. In those cases where this small remainder was not deter-
mined, it was calculated proportionally to the quantity of chlorine. Thus, for instance,
water taken in 44° 33' N. lat. and 42° 54' W. long, contained, in 1000 parts, chlorine
18-842, and silica , &c. 0-069. In water taken in 47° 50' N. lat. and 33° 50' W. long.,
the quantity of chlorine was found to be IT 740, and silica is, according to the former
proportion, calculated as 0-072. In this case the silica, &c. was yyj of the quantity of
the chlorine, and in general it is less than yyy ; thus the possible error is utterly un-
important.
I rejected a method often used, which consists in evaporating sea- water to dryness,
because it is inaccurate, and the result depends partly upon trifling circumstances. If
evaporated by steam of 100° C. there will remain a very notable quantity of water,
which quantity can only be ascertained with great difficulty. If it is dried at a higher
temperature, muriatic acid from the chloride of magnesium will be driven out together
with the water. I preferred thus, as I have already mentioned, to determine the quan-
tity of the five above-named substances, to ascertain under one head all the small quan-
tities of the different substances that remain insoluble in water, such as silica, phosphate
of lime, &c., and to calculate the soda. At first I tried to separate the quantity of all
the different substances in one portion of sea-water, but soon found that this method
was neither so exact nor so easy as that which I shall now explain.
1. Of one portion of 1000 grains, I separated the chlorine by nitrate of oxide of
silver after I had poured a few drops of nitric acid into the water. In those cases
where the water had fermented, I allowed it to stand in an open glass jar, in a warm
place, until all smell of sulphuretted hydrogen had disappeared. To try how exact a
result this method could give, I took a larger portion of sea-water, and weighed three
different portions, each of 3000 grains, and precipitated the chlorine. The result was —
Chloride of silver.
145-451
145-544
145-642
Mean . . 145-541
The greatest difference is
— 0-090 = 0-022 chlorine.
-{-0-083=0-020 chlorine.
These small differences are probably due to the small irregularities occasioned by the
evaporation of very small quantities of water during weighing. The dried chloride of
silver was as much as possible removed from the filter, melted in a porcelain crucible,
216
PEOEESSOE EOECHHAMMEE ON THE COMPOSITION
weighed, and calculated as pure chloride of silver. The filter was burnt in a platinum
crucible, by which the small quantity of chloride of silver was reduced to metallic silver,
from which the chlorine which had been combined with it was calculated. This suppo-
sition is correct if the quantity of chloride of silver adhering to the filter is very small.
2. The determination of the sulphuric acid was likewise made with 1000 grains of
sea-water, which, after addition of some few drops of nitric acid, was precipitated with
nitrate of baryta. To try the exactness of the method three portions of sea-water were
weighed, each of 3000 grains. The result was —
Sulphate of baryta.
12-417
12-316
12-250
Mean . . . 12-328
The greatest difference was
— 0-078=0-027 sulphuric acid.
q-0-089 = 0-030 sulphuric acid.
3. To determine lime and magnesia 2000 grains (in the latter experiments only
1000 grains) were weighed, and mixed with so much of a solution of sal-ammoniac that
pure ammonia did not produce any precipitate, then ammonia was added until the
liquid had a strong smell thereof. It was now precipitated with a solution of the com-
mon phosphate of soda and ammonia, and filtered when the precipitate had collected
into a granular powder. The precipitate thus obtained consists of tribasic phosphate
of lime, and tribasic phosphate of magnesia and ammonia, which was washed with a
weak solution of ammonia. All the filtered solution and the wash-water was evapo-
rated in a steam-bath to dryness, and afterwards digested in a tolerably strong solution
of pure ammonia, by which means there is further obtained a small quantity of the
phosphates. The dry phosphates of lime and magnesia are heated, and if they are not
completely white, they are moistened with a few drops of nitric acid, and again heated
and afterwards weighed. The mass was now dissolved in muriatic acid mixed with
alcohol until the whole contained 60 per cent, (volume) thereof, mixed with a few drops
of sulphuric acid, and allowed to stand for twelve hours, when the sulphate of lime is
collected on a filter, heated and weighed. It contains, besides the sulphate of lime, silica,
oxide of iron, phosphate of alumina, and sulphate of baryta and strontia, from which
substances the sulphate of lime is separated by boiling it with a solution containing
10 per cent, of chloride of sodium, which dissolves the sulphate of lime and leaves the
other combinations undissolved. The remainder is washed, heated, and its weight
deducted from that of the sulphate of lime. To try how exact the determination of the
lime was, I have taken three times 3000 grains of the same water, separated the lime,
and obtained the following results : —
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
217
Sulphate of lime.
2-761
2-753
2- 684
Mean . . . 2-733
The greatest differences are —
-0-049 = 0-020 lime.
+ 0-028=0-012 lime.
To find the quantity of magnesia contained in the weighed mixture of the phosphates
of magnesia and lime, the lime, whose quantity has been determined, must, by calcu-
lation, be converted into tribasic phosphate of lime, and deducted from the whole
quantity of phosphates ; the other small quantities of different salts, which had been
precipitated with the sulphate of lime, must likewise be deducted ; the remainder is
bibasic phosphate of magnesia, from which the pure magnesia is calculated. The sea-
water tried in this way gave, after deduction of lime, silica, &c., the following result: —
Pure magnesia.
3- 913
3-970
3-942
Mean . . . 3-942
The differences from the mean are —
-0-029
+ 0-028
4. The determination of potash or potassium -in sea-water was tried by different me-
thods, but gave no satisfactory results, so that I must consider the quantity of potash in
the analyses as far less exact than any of the other substances whose quantity has been
determined in sea-water. Happily there is so small a quantity of potash in sea-water,
that any error in the determination of that substance has only an insensible influence
on the whole result. For a number of the analyses I have used the following method.
The weighed sea-water was evaporated to dryness, the dry mass again dissolved in water,
and the undissolved residue washed with warm water until all sulphate of lime is dis-
i solved, and the wash-water does not contain any sulphuric acid. The remaining powder
consists of the different after-named salts and oxides insoluble in water ; it is generally
weighed and noted under one head.
To this solution I add so much carbonate of lime that the sulphuric acid finds lime
enough to combine with, and as much muriatic acid as would dissolve the lime of the
carbonate. The quantity of carbonate of lime is determined in the following way.
The equivalent of sulphate of baryta being 1456, and that of carbonate of lime being-
625, there will be an excess of lime if I take carbonate of lime in such a quantity that
218
PROFESSOR FORC1IHAMMER OjST THE COMPOSITION
its weight is one-half of the quantity of sulphate of baryta, obtained from an equal
quantity of the same sea-water in a previous experiment for the determination of sul-
phuric acid. All is now evaporated to dryness and dissolved in alcohol of 60 per cent.,
which leaves the sulphate of lime and dissolves all the chlorides ; so that the solution
is quite free from sulphuric acid. It is now a third time evaporated with a sufficient
quantity of chloride of platinum. Alcohol of 60 per cent, leaves the chloride of plati-
num and potassium, which might be weighed, and the quantity of chloride of potassium
calculated from it ; but as it is most difficult in a laboratory where there is constantly
work going on to avoid the absorption of the vapours of ammonia by evaporating
liquors, I prefer heating the double chloride to a dull red heat, and assisting the
decomposition of the chloride of platinum by throwing small pieces of carbonate of
ammonia in the crucible. When all the chloride of platinum is decomposed, the crucible
is weighed, the chloride of potassium is extracted by alcohol of 60 per cent., and the
remainder weighed again. This method has the advantage, that even if a small quan-
tity of gypsum should have accompanied the double chloride, it will have no influence
upon the determination of the chloride of potassium. When I do not want to
determine the insoluble remainder, I evaporate the sea-water with a sufficient quantity
of chloride of calcium, and thus leave out one evaporation and solution.
In the few cases where I have tried to determine the different substances which in
this chapter I have called silica, &c., I have used the following method. The filter
upon which the remainder is collected and washed is burnt in a platinum crucible,
evaporated with some drops of muriatic acid, and dissolved in water. What remains is
silica, often coloured by a little oxide of iron, and mixed with a small quantity of
sulphates of baryta and strontia. It is evaporated with fluoric acid and a drop of
sulphuric acid to get rid of the silica. What remains after evaporation and heating
is sulphate of baryta, of strontia, and oxide of iron. The solution in muriatic acid is
precipitated by ammonia, and the precipitate is noted as phosphate of lime, but con-
tains besides a little fluoride of calcium. The remaining liquid contains a little lime,
which I precipitate with oxalate of ammonia, and suppose to have been in the sea-water
as carbonate of lime dissolved by carbonic acid. In the water of the great ocean there
occurs only a very small quantity of carbonate of lime, but near the shores, in the
bays and inlets, and principally in the mouth of the great rivers, its quantity increases
with the quantity of fresh water from the land. If the sulphates of the sea-water
are decomposed to sulphurets, there is always precipitated a larger quantity of carbonate
of lime, but that is the result of the decomposition, and its carbonic acid is owing to
the organic substances which are oxidized by the oxygen of the sulphates.
I have never tried to ascertain the nature and quantity of the gases which occur in
sea-water, because the collection of sea-water for that purpose would require quite
different precautions from those which were necessary for the water intended for the
analysis of its solid contents.
It might seem that the relative quantity of salt might be inexact, because water might
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
219
have evaporated through the cork during the long time which often elapsed between
the time when it was taken up from the sea, and the time when it was analyzed. It
is, however, easy to see whether the quantity of water in the bottle has diminished, or
whether the cork has been corroded ; in both cases the sample has been rejected, but I
must remark that these cases have been rare. In the last three or four years all the
samples which have been taken according to my direction have been marked on the neck
of the bottle with a file, on that place to which the water reached when the bottle was
filled.
As to the calculation of the combinations of the different substances that have been
found by the analysis, I have chosen the following method : —
The whole quantity of lime was supposed to be united with sulphuric acid.
What remained of sulphuric acid after the saturation of lime, was supposed to be
combined with magnesia.
What remained of magnesia after the saturation of sulphuric acid, was supposed as
magnesium to enter into combination with chlorine, and form chloride of magnesium.
The potash was supposed to form chloride of potassium.
That portion of chlorine which was not combined with magnesium or potassium, was
supposed to form a neutral combination with sodium.
Lastly, that small quantity of different substances, “ silica, &c.,” was added, and the
sum of all these combinations thus calculated forms the number which in the Tables
is called “All Salts.” It is hardly necessary to remark, that it is quite indifferent how
we suppose the acids and bases to be combined in sea-water, the sum must always
be the same, provided the salts are neutral, and all the acids (chlorine included) are
determined, as well as all the bases, with the exception of soda.
On the Distribution of the Salts in the different parts of the Sea .
The next question to be considered refers to the proportion between all the salts
together and the water ; or to express it in one word, I may allow myself to call it the
salinity of the sea-water, and in connexion with this salinity or strength, the proportion
of the different solid constituent parts among themselves. On comparing the older
chemical analyses of sea-water, we should be led to suppose that the water in the
different seas had, besides its salinity, its own peculiar character expressed by the different
proportions of its most prevalent acids and bases, but the following researches will show
that this difference is very trifling in the ocean, and has a more decided character only
near the shores, in the bays of the sea, and at the mouth of great rivers, wherever
the influence of the land is prevailing.
In the Tables which are annexed to this paper I have always calculated the single
substances and the whole quantity of salt for 1000 parts of sea- water, but besides this
I have calculated the proportion between the different substances determined, referred
to chlorine =100, and of all the salts likewise referred to chlorine. This last number
is found if we divide the sum of all the salts found in 1000 parts of any sea-water by
the quantity of chlorine found in it, and I call it the coefficient of that sample of sea-
mdccclxv. 2 H
220
PEOFESSOE FOECHHAMMEE ON THE COMPOSITION
water. The following remarks, and the Tables which belong to them, will show that
there is a very small difference in the coefficient of the different parts of the ocean, but
that the differences become striking in the neighbourhood of the shores.
A. On the salinity of the surface of the different 'parts of the ocean and its inlets.
In the Tables annexed to this paper I have divided the sea into seventeen regions.
My reason for doing so was that by this method I was able to avoid the prevailing
influence which those parts of the ocean which are best known, and from which I have
most observations, would exert upon the calculations of the mean number for the whole
ocean.
First Region. The Atlantic Ocean between the Equator and 30° N. lat. — The mean of
fourteen complete analyses is 36T69 per 1000 salt; the maximum is 37*908 per 1000,
the minimum 34*283. The maximum lies in 24° 13' N. lat. and 23° 11' W. long.,
about 5° W. from the coast of Africa, where no rivers of any size carry water from the
land, and where the influence of the dry and hot winds of the Sahara is prevailing.
The maximum for the region is also the maximum of surface-water for the whole
Atlantic ; it is equal to the mean salinity of the Mediterranean, and only the maximum
of that sea off the Libyan desert and that of the Red Sea are higher. The minimum
is from 4° 10' S. lat. and 5° 36' W. long, close to the coast of Africa, where the large
masses of fresh water which the great rivers of that region pour into the ocean exercise
their influence. Its coefficient is 1*810.
Second Region. The Atlantic Ocean between 30° N. lad. and a line from the north point
of Scotland to the north point of Newfoundland. — The mean of twenty-four complete
analyses is 35*946 salt, the maximum 36*927, and the minimum 33*854. The maximum
is in 38° 18' N. lat. and 43° 14' W. long, in the middle of the Atlantic; the minimum
occurs in 43° 26' N. lat. and 44° 19' W. long., and is evidently owing to the enormous
quantity of fresh water which the St. Lawrence, through its southern mouth, pours into
the Atlantic. This region is under the influence of the Gulf-stream, and the corre-
sponding South Atlantic region has only a mean salinity of 35*038. Its coefficient is
1*812.
Third Region. The northern part of the Atlantic , between the northern boundary of the
second region , and a line from the south-west cape of Iceland to Sandwich Bay in
Labrador. — The mean salinity deduced from twelve complete analyses is 35*391, its
maximum 36*480, its minimum 34*831. The maximum falls in 55° 45' N. lat. and
20° 30' W. long., just on the boundary of Region 2, the minimum in 60° 25' N. lat.
and 3° 15' W. long., near the large northerly opening of the North Sea. This region
owes evidently its high salinity to the large northern direct branch of the Gulf-stream.
Its coefficient is 1*808.
Fourth Region. This region comprehends the East Greenland current , which flows
along the east coast of Greenland towards the south and west , turns towards the north ,
when it reaches the south promontory of Greenland , runs along the west coast of that
large land into Davis Straits , where it disappears in the polar current from Baffin's Bay.
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
221
— I owe most of the samples from this current to Colonel Schaffner, who took them on
his expedition to Iceland and Greenland connected with the Northern Transatlantic Tele-
graph. The quantities being too small to allow a complete analysis, I have only deter-
mined the quantities of chlorine and sulphuric acid. I have, however, analyzed three
other samples of water from this current taken by Captain Gram, who during many years
commanded one of the Danish Government’s Greenland ships ; and from these three
complete analyses I have deduced the coefficient 1-813, instead of 1-812, which is the
mean coefficient of the whole ocean. Thus I have calculated the mean salinity of the
East Greenland current to be 35-278*, while it is in the third region 35-391, and in the
sea between Norway and Spitzbergen 35-347. These observations about the salinity of
the current, connected with some other observations which will be afterwards discussed,
make it highly probable that the East Greenland current is the returning Gulf-stream.
At all events it is no polar current, which will easily be seen in comparing it with the
Baffin’s Bay current with a salinity 33-281, or the water to the north of Spitzbergen
with 33-623, or the Patagonian polar current, which runs along the west coast of South
America, and has 33-966. Nor is it probable that it comes from the north shores of
Siberia, where such a great number of powerful rivers bring a vast quantity of fresh
water into the sea. Its salinity is so great that it even exceeds that of the South
Atlantic Region, between 30° S. lat. and the line between the Cape of Good Hope and
Cape Horn, whose salinity is only 35-038.
Fifth Region, A. The Baffin's Bay and Davis Straits Begion. — The mean of eight
complete analyses is 33-281, the maximum 34*414, the minimum 32-304. This region
shows the very interesting fact that its salinity increases on passing from latitude 64°
toward the North, being in 64° 32-926, in 67° 33-187, somewhat further to the North
33-446, and in latitude 69° 33*598. This peculiarity is owing to the powerful current
from the Parry Islands, which through different sounds passes into Baffin’s Bay, where
it is mixed with the great quantity of fresh water that comes into the sea from the West
Greenland glaciers. Had this fact been known before the sounds that connect the Parry
Archipelago with Baffin’s Bay were discovered, it might have proved the existence of
these sounds, because bays and inlets show quite the reverse ; the further we get into
them the less saline the water becomes.
Fifth Region, B. The Polar Sea between the North Cape in Norway and Spitzbergen. —
I have eleven samples of water taken on the Swedish Spitzbergen Expedition by Pro-
fessors Nordenskjold and Blomstrand, of which I have rejected one taken in one of
the bays of Spitzbergen, and another belonging to the sea to the north of Spitzbergen.
None of these analyses were complete, and I have only determined the quantity of
chlorine and of sulphuric acid; and even the latter could in several instances not be
determined, since the water had fermented. The mean quantity of chlorine in the nine
remaining samples was 19-507 ; and if we take the mean coefficient of the four North
* If we take the general coefficient of the ocean, 1-812, the salinity of the East Greenland current would be
35-258, which of course makes no material difference.
2 h 2
222
PROFESSOR FORCHHAMMER ON THE COMPOSITION
Atlantic regions (the East Greenland current included), 1-810, 1-812, 1-808, 1-813, it
will be 1-811 ; and if we use this coefficient, the mean salinity of that part of the sea
will be 35-327, or if we take the mean coefficient of the whole ocean, 1-812, it will be
35-347. The maximum was in 76° 15' N. lat. and 13° 15' E. long., with 20-019 chlo-
rine = 36-254 salt; the minimum in 70° 30' N. lat. and 19° 5' E. long., with 18-993
chlorine =34-396, near the coast of Norway, which evidently has had influence upon the
result*.
Fifth Region, C. The Polar Sea to the North of Spitzbergen. — I have only one observa-
tion, of which I owe the sample to Professor Blomstrand. It is from 80° N. lat. and 12°
E. long., containing 18-517 chlorine, which gives, with a coefficient of 1-812, a salinity
of 33-623.
Sixth Region. The German Ocean or the North Sea. — The mean of six complete ana-
lyses is 32-823 per 1000 salt, the maximum is 35 041, the minimum 30-530 per 1000
salt, the maximum is from the mouth of the channel near the Gallopper, and the
minimum is from Heligoland, where the water of the Elbe has a considerable influence.
The mean coefficient is 1-816, which also shows the influence of the land.
Seventh Region. The Kattegat and the Sound. — The quantity of salt in the water of
this region is very variable ; a northerly current and wind brings water which is richer
in salt than that brought by a southerly wind and current. The mean of six complete
analyses and 141 observations, in which only the chlorine was determined, gives 16-230
per 1000 salt, the maximum 23-243, and the minimum 10*869. It must further be
remarked that the proportion of chlorine and lime, which in the whole ocean are in
mean number 100 : 2 -96, in this region are 100 : 3-29, which again must be considered
as depending upon the influence of the land. The mean coefficient is 1-814.
Eighth Region. The Baltic. — The mean numbers are deduced from complete analyses
of samples of sea-water taken on board the Frigate ‘ Bellona,’ on a voyage from
Copenhagen to St. Petersburg, combined with a complete analysis of water from
Svartklubben to the north of Stockholm. Its salinity varies very much in the different
localities, and is of course less in the eastern than in the western portions of the Baltic ;
it varies also in the same place according to wind and current. I found the mean for
this region 4-931 per 1000 salt, the maximum 7-481 in the channel between Bornholm
and Sweden, the minimum in the merchant harbour of Kronstadt =0-610 per 1000 salt.
The mean proportion of chlorine and lime is 100 : 3-64, in the Bay of Finland it is
100 : 7-49. The mean coefficient is 1-835, in the merchant harbour of Kronstadt it is
2-230. The influence of the land is here expressed in these different numbers.
Ninth Region. The Mediterranean. — All my observations lie between the Straits of
Gibraltar and the Greek Archipelago. It is a general belief that the water of the
Mediterranean contains more salt than the water of the ocean in general, and this
opinion depends partly upon some analyses, partly upon the observation that at the
Straits of Gibraltar there is a constant upper-current, which runs into the Mediterranean,
* That this sea is a branch of the Gulf-stream was acknowledged long ago.
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
223
and an under-current which carries its waters into the Atlantic. This opinion of the
superior salinity of the Mediterranean has been completely confirmed by eleven com-
plete analyses of water taken between the Straits of Gibraltar and the Greek Archipe-
lago. The mean salinity of this region is 37*936, while the whole ocean contains
34*388 per 1000 salt. Its coefficient is 1*815. Its maximum (39*257) falls between
the Island of Candia and the African shore off the Libyan desert, as the maximum of
the Atlantic is off the Sahara, but the mean of the Mediterranean is a little higher than
the maximum of the Atlantic ; the whole Mediterranean is under the influence of Africa,
and its hot and dry winds. The minimum for the Mediterranean is at the Straits of
Gibraltar with 36*301 ; the mean salinity of the northern Atlantic Ocean between 30°
and 40° N. lat., but more towards the west, is 36*332 (deduced from eight complete
analyses) ; the surface-water from the Straits of Gibraltar is thus corresponding to that
from the Atlantic of the same latitude. When entering the Straits the quantity of salt
increases rather rapidly, and is at a short distance from them, at 4° 2' W. long., 37*014;
between the Balearic Islands and the Spanish coast it is 38*058, and a little further on
38*321, between the Island of Sardinia and Naples 38*654. Somewhat nearer to the
coast of Malta it decreases to 38*541, and further on towards Greece it decreases again
to 38*013, and would probably decrease more in the direction of the Bosphorus, but I
have no observations from that part of the Mediterranean. From Malta to the coast of
Africa it increases to the maximum of 39*257.
There is another opinion generally reported, that the water of the Mediterranean
contains a greater proportion of magnesia than the water of the ocean. This is, how-
ever, not the case ; the mean proportion between chlorine and magnesia is for the Medi-
terranean 100 : 10*90, and for the ocean 100 : 11*07 ; nor is there any remarkable differ-
ence in the proportions of the other main substances. The proportion between chlorine
and sulphuric acid is for the ocean 100 : 11*89, and for the Mediterranean 100 : 11*82 ;
for lime it is in the ocean 100 : 2*96, and in the Mediterranean 100 : 3*08.
Tenth Begion, A. The Black Sea and the Sea of Assov. — Like the Baltic, the Black
Sea contains sea-water of but little strength, and the mean deduced from three observa-
tions, of which one is from myself, the two others by M. Gobel, is 15*894, maximum
=18*146, minimum =11*880. In my own analysis of water from the Black Sea, fifty
English miles from the Bosphorus, I found the proportion of chlorine 100, to sulphuric
acid 11*71, to lime 4*22, to magnesia 12*64, and thus a considerable increase in the lime
and magnesia.
Tenth Begion, B. The Caspian Sea. — This sea being by many geologists considered to
have been in former times in connexion with the Black Sea, it might be of some interest to
compare its water with that of the Black Sea. I have, however, not had opportunity
of making an analysis of it myself, but have calculated other analyses according to my
method. Of these five analyses four are by M. Mahner, and published by M. Baer in
his ‘ Caspian Studies’ (Caspische Studien). As might be expected, the quantity of saline
matter shows great differences, between 56*814 per 1000 in the Bay of Karassu or
224
PROFESSOR FORCHHAMMER ON THE COMPOSITION
Kaidaik, and 6-236 per 1000. The proportion between chlorine, sulphuric acid, lime,
and magnesia, is
100 : 44-91 : 9-34 : 21-48.
It is quite evident that the Caspian Sea, if it ever had any connexion with the Black
Sea, must have changed its character entirely since that time, and this change might either
be occasioned by the different salts which the rivers brought into the lake, and which
accumulated there by evaporation of the water, or it might be caused by the deposition
of different salts in the basin of the Caspian Sea itself. If we now compare the abnormal
proportions in the Caspian Sea,
Chlorine 100, Sulphuric acid 44-91, Lime 9-34, Magnesia 21*48,
with the normal proportions in the ocean,
Chlorine 100, Sulphuric acid 11*89, Lime 2-96, Magnesia 11-07,
we find that the excess of lime and magnesia will nearly neutralize the excess of sulphuric
acid, and leave only a small quantity of sulphuric acid (3-72), which may be neutralized
by alkalies. Thus rivers which brought sulphate of lime and of magnesia into the Cas-
pian Sea, might in the lapse of 100 and 1000 years certainly change the composition of
its water in the direction which it now has. Its mean coefficient is 2-434.
Eleventh Region. The Atlantic Ocean between the Equator and 30° 8. lat. — The mean
quantity of salts in this region, deduced from seven observations, is 36‘553, the maximum
37-155, the minimum 35-930. The relative quantity of chlorine, sulphuric acid, lime,
and magnesia is 100: 12-03:2-91: 10-96. The water of this region is richer in salt
than the corresponding region in the North Atlantic Sea. Its coefficient is 1-814.
Twelfth Region. The Atlantic Ocean between 30° S. lat. and a line from Cape Horn
to the Cape of Good Hope. — Mean salinity 35-038, maximum 35-907, minimum 34-151;
the maximum not far from the Cape of Good Hope, the minimum not far from the
Falkland Islands. Its salinity is less than the corresponding region in the North
Atlantic (Region 2), which is 35-932, even less than the third and fourth regions (the
East Greenland current), whose salinity is 35-278. This seems partly to depend upon
the Gulf-stream, which causes a considerable evaporation in the northern part of the
Atlantic, partly upon the River Plata in the South Atlantic, which carries an enormous
quantity of fresh water into the southern sea. I have analyzed four samples of sea-
water taken under the influence of that large river. One, taken by Captain Pkevost
in 35° 46' S. lat. and 52° 57' W. long., almost at the mouth of the Plata, contained so
much organic matter that a great part of its sulphuric acid was decomposed, so that the
original quantity of salt could not be ascertained, but the quantity of chlorine, which,
as far as we know, is not affected by the fermentation of the water, was only 17-721,
which, multiplied by 1-808, the coefficient of this region, gives a quantity of salts
— 32-040 ; the other three samples, taken between 40° 30' and 50° 31' S. lat., and 40° 50'
and 52° 15' W. long., are all far below the mean salinity of this region. It deserves to
be remarked, that all the samples from the western part of this region have a less
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
225
quantity of sulphuric acid than the normal, and the samples from the eastern part of the
region nearer to the African coast have a proportion of sulphuric acid which is con-
siderably greater than the normal quantity. Does this depend upon the more prevailing
volcanic character of the west coast of Africa compared to the east coast of America \
Thirteenth Region. The sea between Africa and the East Indian Islands. — The mean
of this region is 33-868, but it is deduced from observations that have given very different
results. The maximum (35’802) is from 31-54 S. lat., 72° 37' E. long., about midway
between the Cape of Good Hope and Australia. Now in the North Atlantic Ocean
even the mean salinity between 30° and 55° N. lat. is 35-932, thus greater than the
maximum in this region, though this maximum is from near 32° S. lat. The fact is
striking. The minimum (25-879) is from a place high up in the Bay of Bengal, and of
course highly influenced by the vast quantity of water from the Ganges. It lies, how-
ever, about 300 English miles from the mouth of the Ganges ; and another specimen
from N. lat. 17° 20', and about sixty miles nearer the mouth of the Ganges, has 32-365
per 1000 salt, so that it seems as if some other cause has also been operating to weaken
the sea-water at the minimum place.
Fourteenth Region. The sea between the south-east coast of Asia , the East Indian
Islands , and the Aleutic Islands. — The mean quantity of salt, deduced from seven com-
plete analyses, is 33-506, the maximum from a place to the south-east of Japan, in
38° 31' N. lat., is only 34*234, less than the maximum of the German Ocean between
50° 60' N. lat., and surrounded by land (35-041). The minimum (32-370) between the
larger East Indian Islands depends evidently upon the influence of the surrounding land.
The mean proportion of chlorine, suphuric acid, lime, magnesia, isl00:ll-76: 3-05:10-99,
very nearly normal. The mean coefficient is 1-815.
Fifteenth Region. The sea between the Aleutic Islands and the Society Islands , between
38° N. lat. and 32° S. lat. — The mean quantity of salt is only 35-219, which is very
near the mean of the East Greenland current (35-278), and very much below the mean
of the Atlantic between 30° S. and 30° N. lat., which is 36-321. Its maximum is 36-061
near Borabora, about 16° S. lat., while the maximum of the corresponding tropical part
of the Atlantic is 37-908 ; its minimum, under 38° 26' N. lat., very far from any land, is
34-157. The mean proportion of chlorine, sulphuric acid, lime, and magnesia is
100 : 11-67 : 2-93 : 11-06. The mean coefficient is 1-806.
Sixteenth Region. The Patagonian cold-water current. — Mean 33-966 per 1000, maxi-
mum 34-152, minimum 33-788. The minimum is in the southernmost part of this current,
and the maximum under 35° 22' S. lat. The mean proportion of chlorine, sulphuric acid,
lime, and magnesia is 100 : 11-78 : 2'88 : 11-04. The mean coefficient is 1-806.
Seventeenth Region. The South Polar Sea. — I have only three analyses, all on
samples taken by the late Sir James Ross. One was from 77° 32' S. lat., 188° 21' E.
long., close to the great ice-barrier. The water was full of animalculae, but, notwith-
standing, had not fermented. The quantity of salt which it contained was 28-565 per
1000. The next sample was from 74° 15' S. lat., 167° E. long. ; the water was muddy,
226
PEOFESSOE FOECHHAMMEE ON THE COMPOSITION
probably from animalculae and diatomacese. The place was not far from Victoria Land,
at some distance from Coulman Island. It contained only 15-598 salt. The third, from
65° 57' S. lat., 164° 37' E. long., had the surprising quantity of salt 37‘513 per 1000.
The mean of these three observations is 27’225 per 1000 ; but this mean number is of
very little consequence, being derived from numbers differing so greatly. It is, however,
very surprising that water from the neighbourhood of the supposed Antarctic continent
should have a salinity higher than any one found in the south equatorial regions of the
Atlantic, and only be exceeded by a single one in the North Atlantic regions. I am
sure that no material fault exists in the analysis, and this curious fact must thus remain
unexplained until repeated observations in that region shall procure us further informa-
tion. Should the observation be proved to be correct, it would render the existence of
a “ Gulf-stream ” in the Antarctic zone very probable. There is still another peculiarity
in these observations which deserves attention, viz. the great proportion of sulphuric
acid to chlorine. In the water in the neighbourhood of Coulman’s Island it is
12-47 : 100, and in that from 65° 57' S. lat. 12-55 : 100, while in the whole ocean it
is as 11‘89 : 100. This might depend upon the very pronounced volcanic character of
the Antarctic continent. There is still one question to be discussed with respect to
the Antarctic Sea, how it is to enter into the mean numbers of the whole ocean. The
observation from the neighbourhood of Coulman’s Island must be rejected, because it is
too near the land, and we have no corresponding observations from the open Antarctic
Ocean. Its high coefficient (1*861) shows the great influence of the neighbouring land.
The observation from 65° 57' S. lat. must also be rejected as doubtful; there remains
only the observation from the neighbourhood of the great ice-barrier, and I have taken
that for the mean of the Antarctic region.
General Results of the preceding investigation.
If we except the North Sea, the Kattegat, Sound, and Baltic, the Mediterranean and
Black Sea, the Caribbean Sea and the Bed Sea, which have all the characters of bays
of the great ocean, the mean numbers are the following : —
Sea-water.
Chlorine.
Sulphuric acid.
Lime.
Magnesia.
All salts.
Coefficient.
1000
18-999
2-258
0-556
2-096
34*404
1*812
100
11-88
2-93
11-03
Equivalents
429
45
16
82
Thus it is evident that sea-water in its totality is as little a chemical compound as the
atmospheric air ; that it is composed of solutions of different chemical compounds ; that
it is neutral, because it everywhere in the atmosphere finds carbonic acid to neutralize
its bases, and everywhere on its bottom and shores finds carbonate of lime to neutralize
any prevailing strong acid ; that, lastly, the great stability of its composition depends
upon its enormous mass and its constant motion, which occasions that any local varia-
tion is evanescent compared to the whole quantity of salt.
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
227
If we take the mean numbers for the five regions of the Atlantic between the south-
ernmost point of Greenland and that of South America, we find the mean quantity of
salt for the whole Atlantic 35*833, while the sea between Africa and the East Indies
has only 33-850, the sea between the East Indies and the Aleutic Islands 33*569, and
the South Sea, between the Aleutic Islands and the Society Islands, 35-219 per 1000 salt.
The Atlantic is thus that part of the ocean which contains the greatest proportion of
salt, which result is rather surprising if we consider the vast quantity of fresh water
which the rivers of Africa, America, and Europe pour into it : of Africa four-fifths are
drained into the Atlantic either directly or through the Mediterranean ; it is most pro-
bably nine-tenths of America which is drained into the Atlantic, since the Cordilleras
run close to the western shore of the continent ; and of Europe, also, about nine-tenths
of the surface sends its superfluous water to the Atlantic. This greater quantity of
fresh water from the land, and the greater quantity of salts in the corresponding sea,
seem to contradict each other, but can be explained by a higher temperature, and, as the
result of this higher temperature, a greater evaporation.
Some of the large bays of the ocean have in the tropical or subtropical zone a greater
mean than the Atlantic: such are the Mediterranean, with 37-936 per 1000 salt (mean
of eleven observations); the Caribbean Sea, with 36-104 per 1000 (one observation);
the Eed Sea, 43-067 per 1000 (mean of two but little differing observations), which is
the greatest salinity of the sea I know of.
In approaching the shores the sea-water becomes less rich in salts, a fact which finds
its explanation in the more or less great quantity of fresh water which runs into the
sea. On such shores where only small rivers flow out, the effect produced is but very
trifling, as, for instance, on the western shores of South America. The effect of large
rivers in diluting the sea-water is much greater than is generally supposed ; thus the
effect of the La Plata river, whose mouth lies in about 35° of S. latitude, was still
observable in a sample of sea-water taken at 50° 31' S. lat., at a distance of 15° of lati-
tude, or 900 English miles from the mouth of the river; at about the same distance,
the water of the North -Atlantic Sea suffered a considerable depression in salinity, pro-
bably owing to the water of the St. Lawrence. This influence is of a double kind,
partly in diluting the sea-water, partly in mixing it up with organic substances that
will occasion its decomposition by putrefaction.
The polar currents contain less salt than the equatorial. I have determined the
quantity and nature of the salts in two very well-defined polar currents, — the West-
Greenland polar current, with 33-176 per 1000 salt, and the Antarctic polar or Pata-
gonian current, on the west side of South America, which contains 33-966. It is highly
interesting to observe that the East Greenland current, which according to its geogra-
phical relations might be considered as a polar current, which in fact has been con-
sidered in that way, has a very high mean quantity of salt, viz. 35*278 per 1000, while
the sea to the north of Spitzbergen, according to one analysis, contains 33-623 per 1000
salt. I think I shall afterwards, from other phenomena also, prove that the East
mdccclxv. 2 i
228
PROFESSOR EORCHHAMMER ON THE COMPOSITION
Greenland current is a returning branch of the Gulf-stream ; but I may here remark
that the great quantity of salt which it contains almost by itself proves the more equa-
torial nature of this current.
As to the chemical substances which constitute the salts of the sea-water, it must be
remarked that the polar current of West Greenland contains a larger quantity of sul-
phuric acid than any other region, with the exception of the south polar region and the
East Greenland current.
The proportion between chlorine and sulphuric acid is —
For the West Greenland current .
For the East Greenland current .
Near Coulman’s Island, Victoria Land
From 65° 57' S. lat
100 : 12-27
100 : 12-34
100 : 12-47
100 : 12-55
The mean proportion for the ocean is
100 : 11-89
This excess of sulphuric acid in the Antarctic Sea might be explained by the decided
volcanic character of its islands and shores ; even for the East Greenland current, the
neighbourhood of Iceland and its volcanos might account for the excess of sulphuric
acid; but the West Greenland polar current is under no such influence, and the sur-
face-water of the Mediterranean, where so many volcanos exist, has 11-82 sulphuric
acid, which is even a little below the mean proportion, 11-89. Only the water from the
depth of the Mediterranean has an increased proportion of sulphuric acid, viz. 12-07.
Thus it appears improbable that the excess of sulphuric acid in these polar regions
should be owing only to volcanic action. It might depend upon the want of fucoidal
plants. I have formerly, in a paper printed in the Report of the British Association for
1844, shown that the fucus tribe has a great attraction for sulphuric acid, and that the
sulphuric acid, by the putrefaction of the plant, is reduced to soluble sulphurets and to
sulphuretted hydrogen, which with the oxide of iron, which is partly dissolved, partly
suspended in water, will form sulphuret of iron. Thus the sulphur will disappear from
sea-water, and a great quantity of sea-weeds will diminish the quantity of sulphuric acid
in the sea- water. Now it is well known that the polar regions have few or no sea-weeds,
and Sir James Ross, when returning from the Antarctic polar region, remarks expressly
that he observed the first sea-weed very far from the southernmost port of his voyage.
An unusually small quantity of sulphuric acid seems to exist in the first of my regions,
that part of the Atlantic which lies between the Equator and 30° N. lat., its relative
quantity being 11*75. Does that depend upon the Sargassum Seal
The greatest proportion of lime in the ocean occurs in its second region, the middle
part of the northern Atlantic, where its proportion is 3"07, the mean proportion being
2*96; the least quantity of lime is found in the West Greenland polar current, with a
proportion of 2-77 ; and next to that in the Patagonian polar current, with a proportion
of 2*88. Wherever in other regions the influence of land is prevailing, the lime is like-
wise prevailing. In the Baltic I found its proportion 3-59, in the Kattegat 3-29, in that
Or SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
229
part of the German Ocean which lies close to the Kattegat 3*15, and in the whole
German Ocean 2 -87. In a sample from the Black Sea which I analyzed I found it 4-22.
B. On the difference of the contents of Sea-water at the surface and in different,
depths.
It would be natural to suppose that the quantity of salts in sea-water would increase
with the depth, as it seems quite reasonable that the specific gravity of sea-water would
cause such an arrangement. But this difference in specific gravity relative to the
increase in the quantity of salts is counteracted by the decreasing temperature from the
surface to the bottom. We have parts of the sea where the .quantity of solid salts
increases with the depth ; in other parts it decreases with the increasing depth ; in
other places hardly any difference can be found between surface and depth ; and, lastly,
I have found one instance where water of a certain depth contained more salt than both
that aboveand below. These differences are to a great extent dependent upon currents
both on the surface and in different depths. The phenomenon of double currents at
the Straits of Gibraltar has been long known, and in close connexion with these double
currents the saline contents of the water of the Mediterranean increase in quantity with;
the depth. There is, however, one exception in the Mediterranean, under interesting
circumstances, which I shall afterwards discuss more at length. I have made eleven
complete analyses of the surface-water of the Mediterranean, and calculated another
quoted in Violette et Archambault, ‘ Dictionnaire des analyses chimiques,’ vol. i.
p. 358, without a more exact reference to the place where it was taken. Of my own
analyses, one must be rejected on account of the great quantity of sulphuretted hydro*
gen that had been formed, and of course caused a loss of sulphuric acid ; but it causes
also a loss of lime, because the formation of sulphuretted hydrogen is contemporaneous
with the formation of carbonic acid, which will precipitate the lime when deprived of
its sulphuric acid. The mean number of the remaining analyses of surface-water is
20889 per 1000 for the chlorine, and 37‘936 for all salts. The mean number for chlo-
rine of eight analyses of water taken from a depth of between 300 to 600 feet is 21T38.
In each case the deep water was richer in chlorine than that from the surfaoe, except in
one instance, where the chlorine of the surface-water was 21 '718, and all salts, calcu-
lated from a complete analysis, were 39*257 per 1000, while the chlorine of water taken
from a depth of 522 feet was 21-521 per 1000. This curious exception occurred
between Candia and the African coast, where the dry and hot winds from the neigh-
bouring Libyan desert evidently cause a strong evaporation and a considerable eleva-
tion of temperature, which counteract each other as to specific gravity. The difference
between the upper and lower current in the Straits of Gibraltar is, in the surface-water,,
chlorine 20-160 per 1000, all salts 36*391, and in the depth of 540 feet, chlorine 20-330.
The cause why the surface-current is Atlantic water flowing into the Mediterranean,,
and the under-current Mediterranean water flowing into the Atlantic, has long since been
assigned to depend upon the comparatively small quantity of water that flows from the
land into the Mediterranean, and the hot and dry African winds that cause more water
2 i 2
230
PROFESSOR FORCHHAMMER ON THE COMPOSITION
to evaporate than the rivers bring into the sea. My analyses have not given me any
reason to alter anything in our views of the cause of this difference, nor do I regard the
single instance of water that is more rich in salts at the surface than in the depth as
more than a local exception.
As to the difference between surface and deep water for other substances, I shall only
remark that the deep water of the Mediterranean contains a remarkable excess of sul-
phuric acid. The proportion between chlorine and sulphuric acid is
For the whole ocean . . . 100 : 11-89
Mediterranean surface . . . 100 : 11-82
Mediterranean depth . . . 100 : 12-07
Already in the Straits of Gibraltar the difference has the same character. The proportion is
For the surface 100 : 11-42
For the deep water .... 100 : 11-93
In some places, however, in the Mediterranean the surface-water is richer in sulphuric
acid than water from the depth ; thus, for instance, the sea between Sardinia and Naples
had a proportion of 12-55 sulphuric acid in surface-water.
In the Baltic we have the same phenomenon ; the water from the depth contains
likewise more salt than that from the surface, but the direction of the currents is the
reverse. The upper-current goes generally (not always) out of the Baltic, and the under-
current goes, as it would appear, always into the Baltic. The cause of this great differ-
ence between the Baltic and the Mediterranean is evident ; the Baltic receives the excess
of atmospheric water from a great part of Europe. The greater part of Sweden, the
greater part of European Russia, and a great part of North Germany send their water
into the Baltic, and the evaporation is comparatively small. Thus the excess must find
its way through the Sound and the Belts. With the assistance of Captain Prosilius,
who in the year 1846 commanded the vessel at the station of Elsinore, the surface-
current was observed on 134 days, from the 27th of April to the 11th of September ;
of which on 24 days it ran from the north, on 86 days from the south, and on 24 days
there was no surface-current at all. The quantity of chlorine was determined for every
sample by titration, and from that the quantity of salt deduced by multiplication with
the determined coefficient 1-812. The mean quantity of salt for the current from the
North was 15*994 per 1000; that for the current from the South 11-801 ; that for the
period when there was no current at all was 13-342. Once a week a sample was taken
from the bottom, by sending a reversed bottle down to the bottom, turning it there,
and after having allowed it to stand some time, taking it slowly up. The mean of
nineteen observations was 19-002 per 1000 salt, which, according to the manner in which
the samples were taken, is rather under than above the real mean, and proves clearly
that it is water from the Kattegat which runs at the bottom of the Sound. But we
have also direct observations of the same fact. Some years ago a steamer was, close to
Elsinore, struck by another steamer, and sunk a very short time after the collision.
Or SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
231
When afterw ards, in quiet sea, without current, a diver went down to save the passen-
gers’ goods, he found a violent current from the North. To the same class of pheno-
mena belongs also the observation that large deep-going vessels not unfrequently go on
in the Sound against surface-current, where smaller vessels do not succeed.
This under-current of Elsinore reaches often, and perhaps always, the harbour of
Copenhagen, which I ascertained by a series of observations for which the laying of
gas- and water-pipes offered me a good opportunity. To carry these pipes under the
harbour, from Copenhagen to Christianshaven, on the Island Amager, a tunnel was pro-
jected through a solid hard limestone of the chalk formation, which lies under Copen-
hagen, its harbour, and its neighbourhood. When the tunnel was completed, it was
found that the sea-water slowly filtered through the limestone, and fell down in drops
from the roof of the tunnel. Comparative analyses would show how the water of the
bottom of the harbour differed from that of the surface, and I might at the same time
clear up another rather important question. It is generally known that the question of
the formation of the dolomites, or the double carbonates of lime and magnesia, has
excited a great interest, and many theories have been proposed about their formation.
I myself have shown that a solution of carbonate of lime in carbonic acid water, when
poured into sea-water, precipitates both carbonate of lime and carbonate of magnesia, but
that the quantity of magnesia increases with the increased temperature in which the
decomposition takes place. Neutral carbonate of lime thrown into sea-water would
however, even at the boiling-point, not precipitate any carbonate of magnesia. It might,
however, be a question of time, and it might be possible that such a decomposition
would take place if sea- water during a long time was in close connexion with solid
carbonate of lime. This would be the case if sea-water slowly filtered through 30 feet of
solid limestone, which it does in the tunnel. We cannot, of course, expect to obtain
any result by comparative analyses of the limestone ; any change in the composition of
this great mass of limestone would be so small that no result could be drawn from it, but
we might analyze the sea-water filtered through the stone, and determine very small
changes in its composition. Thus a series of comparative analyses of the sea- water from
the surface of the harbour, of that from the bottom of it, and of the water filtered through
the limestone into the tunnel, would show, first, whether the under-current from Elsinore
reaches the harbour of Copenhagen ; and secondly, whether the limestone roof of the
tunnel acts upon the salts of magnesia in the sea-water which filters through it.
The experiments were made in the following way: once a week, from the 3rd of
March to the 25th of April, 1852, one sample was taken of sea-water from the surface
of the harbour over the tunnel, another sample from the bottom of the harbour at the
same place, and a third sample was collected from the filtering water in the tunnel.
The mean of these analyses gave,
For the surface 15-845 per 1000 salt
For the bottom of the harbour . 17-546 „
For the tunnel 18-315 „
232
PROFESSOR FORCHHAMMER ON THE COMPOSITION
which, seems to prove that the under-current from Elsinore, at least at that season,
reached Copenhagen. The difference between the water from the bottom of the har-
bour and the tunnel might either be occasioned by the slowness with which the water
filters through the limestone of 30 feet thickness, so that it was water from another
period which at last reaches the tunnel, or it may be explained by the way in which the
samples from the bottom were taken, by sending an open bottle reversed down to the
bottom, where it was turned and allowed to stand some time, to let the heavier water
from the bottom dislodge the lighter water which had entered the bottle. The mean
relative quantity of lime and magnesia was —
For the surface . . 1 lime to 4-062 magnesia.
For the bottom . . 1 lime to 4-153 magnesia.
For the tunnel . . 1 lime to 3-485 magnesia.
The proportion between lime and magnesia is therefore pretty much the same in the
water from the surface and the bottom of the harbour, but in the water from the
tunnel the relative proportion of the lime is increased. This may depend either upon
a diminution of the magnesia, or upon an increase of the lime, or upon a combination
of both effects ; but if these changes took place only according to equivalents, it would
prove that there had been formed dolomitic combination by the filtration of the mag-
nesia salts of sea-water through the carbonate of lime in the limestone. To ascertain
this point, I have compared the lime and magnesia with a third substance in sea-water,
for which I chose chlorine. This mean proportion was —
For the surface . . 100 chlorine : 2-82 lime : 11-07 magnesia.
For the bottom . . 100 chlorine : 2-62 lime : 10-96 magnesia.
For the tunnel . . 100 chlorine : 3-11 lime : 11-08 magnesia.
It follows from these comparisons that the absolute quantity of lime had increased
in the water of the tunnel, but that the absolute quantity of the magnesia in the same
filtered water had not decreased, but was as nearly the same as an analysis could show.
Thus the increase of the lime depended upon the solution of some carbonate of lime
from the limestone. It was further found that water from the tunnel, when evaporated
to dryness and dissolved, left more carbonate of lime than surface-water. The cause of
this solution of the carbonate of lime was evidently to be sought in a bed of black mud
which covers the bottom of the harbour, and is slowly converted into carbonic acid by
the atmospheric oxygen absorbed by the sea-water. The sea-water impregnated with
carbonic acid had dissolved some of the limestone through which it filtered.
Here might also be the place to mention and explain a rather curious phenomenon
which is observed all along our coasts of the 'Sound and the Baltic, at least as far as
Kiel. When the ice in spring begins to thaw, it disappears quite suddenly, and all the
fishermen along the shore assure you. unanimously that it sinks. I have examined a
great number of these men, and have .not found a single one who did not confirm the
sudden disappearance of the ice in spring,, and who did not consider it to be quite
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
238
certain that the ice in spring sinks. I could, however, not find a single one of them who
had in spring fished the ice up in his nets, while they very often in autumn and the
beginning of the winter find it at the bottomland see it rise to the surface*. It was
evident that the sudden disappearance of the ice in spring was the fact which they had
observed, and that the sinking of the ice was the popular explanation of the fact.
The natural philosopher will not allow ice to sink in sea-water, and it seems neces-
sary to find another explanation. In order to give that I must first mention another pecu-
liarity with the under-current of Elsinore. I observed on the 2nd of March, 1850, the
temperature of the under-current with a maximum thermometer to be +2'6 C. (360,8F.)
at the depth of 108 feet, while the temperature at the surface was +1'6 G. (340,9 F.).
Early in the next spring a friend of mine repeated the observation, and found likewise
the higher temperature in the under-current, the difference being about 2° C. A third
observation made in summer gave no difference. To explain this, I must observe that the
Water of the Kattegat, at least in its depth, is a branch of that great part of the Gulf-
stream that passes along the western shores of Norway, and that the under-current at
Elsinore necessarily must be less affected by the cold which reigns over the Baltic in winter
time. Thus the under-current has in spring a higher temperature than the water of the
surface, and at the same time contains a greater quantity of salt. Suppose, now, that the
ice towards spring has begun to thaw and has become porous, as is generally the case, the.
warmer and more saline water will come in contact with it from below, and will melt it,,
partly on account of its temperature above freezing-point, partly on account of the greater
quantity of salt which it contains. Thus without any apparent greater changes on the-
surface the ice will melt quickly and almost imperceptibly, and disappear. This effect
of the under-current will be increased by the peculiarity of sea-water, that its point of
greatest density lies below the freezing-point of pure water, and a constant series of
small vertical currents will be formed where the warmer water rises, and that which is
refrigerated by the contact with the ice sinks, which motion always will increase the
melting of the surface-ice.
Besides at Elsinore and at Copenhagen, it has been observed at Kiel, near Stockholm,
and in the Bay of Finland, that the deeper water is more saline than that of the surface.
At Svartklubben, near Stockholm, water from the surface contained 3-256 chlorine
'=5-919 salt, and from a depth of 720 feet 3-912 chlorine =7T82 salt (coefficient
T836); in the Bay of Finland, between the islands Nervoe and Sukjeld, the surface-
water contained 3-552 per 1000 salt, while in a depth of 180 feet it contained 4*921.
It was only for the two larger salt-water basins of Europe, the Mediterranean and
* This formation of the bottom ice is very frequently observed on our shores. There is a fishing bank a little
to the north of Elsinore, where the fishermen often in the beginning of the winter find themselves suddenly
surrounded by ice, which they see rise through the water, containing numerous pieces of Fucus inclosed in its
• mass. The same fact has also been observed not. far from Copenhagen, and off Nyborg in the Great Belt. It
seems, in fact, a phenomenon peculiar to such places where a strong current runs over a place that is not very
deep.
234
PROFESSOR EORCHIIAMMER ON THE COMPOSITION
the Baltic, that I was able to determine the quantity of salt near the surface and in the
depth, but it is very probable that similar differences also may occur in other large
inlets of the ocean. I want, however, direct observations in sufficient number, and
shall here only mention an observation from the Caribbean Sea, where surface-water
contained 19-936 chlorine, and water from a depth of 1170 feet contained 19*823 per
1000 chlorine. This difference in which the deeper water is less saline may be another
instance of the effect of hot winds, like the water from the Mediterranean between
Africa and the Island of Candia.
Going on now to the main section of the ocean, we will begin with the Atlantic,
about which we have the best information, and which seems to show the most interesting
facts. I will state the results of my investigations in moving from Baffin’s Bay towards
the south. In Baffin’s Bay itself the water of the surface contains the same quantity of
salt as that of the depth, but as soon as we pass the southernmost point of Greenland, the
water of the surface contains more salt than that from the depth. This difference
increases in going towards the Equator, and is indeed very considerable near that line.
About the Equator, and a little to the south of it, many irregularities appear, as, for
instance, in one case where the strongest water was found between two weaker portions
above and below. In other cases the quantity of salt decreased with the depth, and in
some instances it increased with it. I shall now state the observations themselves.
Dr. Rink; sent me water from the surface in Baffin’s Bay to the west of Disco Island, Avhich
contained 33-594 per 1000 salt, and at the same place from a depth of 420 feet, which
contained 33-607. The difference is so small that it signifies nothing. At the southern-
most point of Greenland a small difference is observed, viz. in 59° 45' N. lat. and 39° 4'
W. long., where surface-water contains 35-067, and that from a depth of 270 feet 34-963;
but in about the same latitude and about 13° further towards W., at 59° 42' N. lat. and
51° 20' long., the proportion was reversed, the surface-water contained 34-876 per 1000
salt, while that from the depth contained 34-975 per 1000. From the sea between
Iceland and Greenland (in which it appears that a returning branch of the Gulf-stream,
the East Greenland current, runs towards the S.W.) I have obtained eight specimens
from a depth between 1 200-1800 feet. Unfortunately no specimens of water from the
surface were taken at the same time, but we have a sufficient number of other surface
observations, and thus we may compare the mean numbers, which are 35*356 for the
surface, and 35-057 for a depth between 1200-1800 feet. In comparing the single obser-
vations of the deep water, we find that it contains the greatest quantity of salt in the
eastern part at 35° 1' W. long., with 35-179 per 1000 salt, decreasing regularly towards
the westernmost part of this region in 55° 40' W. long., with a quantity of salt =34-858
per 1000. Specimens taken by Captain Gram in 59° 50' N. lat. and 7° 52' W. long.,
contained for surface-water 35-576 per 1000, and for water from 270 feet depth
35-462.
I have two other comparative analyses of water from the East Greenland current, of
which I owe the specimens to Colonel Schaffner. The analyses were not made com-
ON SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
235
plete, but only chlorine and sulphuric acid were determined, which gives at 64° 30' N.
lat. and 26° 24' W. long.,
for the surface,
19-616 chlorine, which with a coefficient 1-812 is =35-544 salt;
for a depth of 1020 feet,
19-504 chlorine, which with a coefficient 1-812 is =35-341 salt.
The next analysis of water from 62° 47' N. lat. and 37° 31'-5 W. long., gave
for the surface,
19-491 chlorine =35*318 per 1000 salt;
for a depth of 1200 feet,
19-466 chlorine =35-272 per 1000 salt.
Further to the S.W., near the bank of Newfoundland, specimens taken by Captain
von Dockum gave,
for the surface,
36-360 per 1000 salt;
for a depth of 240 feet,
36-598 per 1000 salt,
which is an increasing quantity of salt for the deep water, and coincides with other
observations which show that this curious decreasing of the quantity of salt, with the
increasing depth, belongs only to the deep part of the Atlantic far from the shores. On
the European side of that ocean three samples, taken by Captain Schulz at 47° 15' N.
lat. and 9° 30' W. long., gave the following quantities of salt; —
from the surface,
35-922 per 1000;
from a depth of 390 feet,
35-925 per 1000 ;
from a depth of 510 feet,
36"033 per 1000 ;
thus showing a trifling increase of salt with the depth.
The most complete set of experiments showing this influence of the shores, I have
made on twelve samples taken by the ‘Porcupine’ in 1862, which I owe to the
obliging kindness of Rear-Admiral FitzRoy. The samples are taken between 50° 56'
and 55° 22' N. lat., and 12° 6' and 15° 59' W. long., about four degrees to eight degrees
of longitude to the west of Ireland, and five of them were from the surface, while seven
were from deep water, between 1200 and 10,500 feet.
The mean of the five surface observations
Chlorine. Sulphuric acid. Lime.
is —
Potash.
Magnesia.
All salts.
19-662 2-342 0-566
0-367
2-205
35-613.
The mean of the seven observations from the deep
sea is —
Chlorine. Sulphuric acid. Lime.
Potash.
Magnesia.
All salts.
19-677 2-357 0-583
0-363
2-193
35-687
2 K
MDCCCLXV.
236
PROFESSOR, EORCHHAMMER ON THE COMPOSITION
Chlorine =100, the proportions are —
Chlorine.
Sulphuric acid.
Lime.
Potash.
Magnesia.
All salts.
For surface . .
. 100
11-91
2-88
1-87
11-21
181-1
For deep water .
. 100
11-98
2-96
1-84
11*14
181-4
The difference is very trifling, and the quantities of salts increase in a very slight degree
with the depth.
I owe all the other samples from the North Atlantic Ocean which have been used for
my analyses, of which I am now going to give the results, to the late Sir James Eoss,
through the assistance of the most honourable and learned President of the Royal
Society, General Sabine, who always is most willing to assist scientific labours with his
powerful influence and his prudent advice, and to whose intercession I am indebted for
several of the most interesting results I have obtained in this investigation.
At 18° 16' N. lat. and 29° 56' W. long.,
from the surface,
20-429 chlorine =36-833 per 1000 saltf °°e“
r { of water from Sir J. Ross=l*803);
from 3609 feet,
19-666 chlorine =35*448 per 1000 salt.
At 16° 27' N. lat and 29° W. long.,
from the surface,
20-186 chlorine =36-395 per 1000 salt (coefficient 1-803);
from 900 feet,
20-029 chlorine =36*112 per 1000 salt (coefficient 1-803);
from 2700 feet,
19- 602 chlorine =35-342 per 1000 salt (coefficient 1*803).
At 15° 38' N. lat. and 28° 10' W. long.
from the surface,
20- 081 chlorine =36-206 per 1000 salt (coefficient 1-803) ;
from 3360 feet,
19-744 chlorine =35-598 per 1000 salt (coefficient 1-803).
At 14° 18' N. lat. and 27° 15' W. long., surface observation wanting;
from 900 feet,
19*934 chlorine =35*941 per 1000 salt (coefficient 1*803);
from 2700 feet,
19- 580 chlorine =35*303 per 1000 salt (coefficient 1*803) ;
from 3600 feet,
19*705 chlorine =35*528 per 1000 salt (coefficient 1-803).
At 12° 36' N. lat. and 25° 35' W. long.,
from the surface,
20- 114 chlorine =36*195 per 1000 salt (direct observation) ;
from 11,100 feet,
19-517 chlorine =35*170 per 1000 salt (direct observation).
or SEA- WATER IN THE DIFFERENT PARTS OE THE OCEAN.
237
At 11° 43' N. lat. and 25° 6' W. long.,
from the surface,
20-035 chlorine = 36-123 per 1000 salt;
from 3600 feet,
19-855 chlorine =35*799 per 1000 salt;
from 4500 feet,
19-723 chlorine =35-561 per 1000 salt.
At 1° 10' N. lat. and 25° 54' W. long.,
from the surface,
19-757 chlorine =35-622 per 1000 salt;
from 1800 feet,
19*715 chlorine =35*546 per 1000 salt;
from 3600 feet,
19-548 chlorine =35*245 per 1000 salt.
For the South Atlantic Ocean, the relation between the salts of the upper and lower
parts of the sea is variable and difficult to explain. In 0° 15' S. lat. and 25° 54' W. long,
the quantity of salts found in different depths was as follows : —
from the surface, wanting ;
from 900 feet,
19-763 chlorine =35-820 (coefficient 1-814);
from 1800 feet,
19- 991 chlorine =36-264 (coefficient 1-814);.
from 4500 feet,
19*786 chlorine =35*892 (coefficient 1-814);,
from 5400 feet,
20*007 chlorine =36-293 (coefficient 1-814).
Most deviating is a series of observations from 22° 37' S. lat. and 34° 57' W. long. : — <
from the surface,
20- 397 chlorine =37-000 (coefficient 1-814);
from 900 feet,
20-323 chlorine =36*866 (coefficient 1-814);
from 1800 feet,
23*189 chlorine =42-165 (coefficient 1-814);,
from 2700 feet,
20-331 chlorine =36-880 (coefficient 1*814);
from 3600 feet,
20-405 chlorine =37*015 (coefficient 1*814).
Already in the water from different depths immediately on the south side of the
Equator there is a curious variation ; at 1800 feet it is about one-half per 1000 richer in
salt than at 900 feet, and in 4500 feet the quantity of salt has diminished as much as it
2 k 2
238
PROFESSOR FORCHHAMMER ON THE COMPOSITION
had increased before. At 5400 feet it has a greater quantity of salt than any of the
upper specimens has shown. In the series from 22° 37' S. lat. the surface has a high
number, higher than any corresponding sample from the North Atlantic, it sinks a little
at 900 feet, but rises at 1800 feet to a quantity of salt which does not occur in any
other place in the whole Atlantic, not even the maximum of the Mediterranean, and
we know only the Red Sea which exceeds it ; it is as if the water of the Red Sea were
transported to this submarine current. I thought there might be a fault in the deter-
mination of the chlorine, and repeated it; but the difference was very insignificant,
being in the one case 23-187, in the other 23-191, the mean being 23-189. I thought
that by some accident some salt might have come into the instrument by which the
water was taken, and I made a complete analysis of the water, but the different sub-
stances which were determined showed but slight differences from the normal propor-
tions, viz. —
Chlorine.
Sulphuric acid. Lime.
Potash.
Magnesia.
22° 37' S. lat., 1800 feet .
. 100
11-59 2-77
2-14
11-29
South Atlantic ....
. 100
12-03 2-91
—
10-96
might perhaps be owing
to an evaporation in the bottle,
but then the
bottle was
full, and cork and sealing-wax were sound, while about one-seventh of its whole con
tents must have been evaporated to explain the difference. If there is any mistake in
this curious observation, it must probably have been caused by a negligence which left
the instrument for taking the water from the deeper part of the sea partly filled with
sea-water, exposed to evaporation in tropical heat, and sent it down without being
cleaned. I should hardly think that such a fault could have been committed, and we
must hope that new experiments will confirm the fact. The series of observations from
0° 15' S. lat. belong in fact to the same kind, by the alternation of stronger and weaker
sea-water in different depths ; but the curious and surprising fact in the observation
from 22° 37' S. lat. is, that in the whole Atlantic Ocean we do not know a single place
where water with that quantity of salt occurs. The next specimen, from 22° 37' S. lat.
and a depth of 2700 feet, is very nearly the same as that from 900 feet, and that from
5400 feet very near that from the surface of the same place.
It appears thus that the water of the North Atlantic Ocean, between the southernmost
part of Greenland and the equator, decreases in salinity with the depth, but that this
curious fact is observed only in the middle bed of the Atlantic, and disappears when
we approach the shores on both sides of the ocean. As to the cause of this rather
surprising state, I am still of the same opinion which I expressed when I first observed
it, that it depends upon a polar under-current. The hypothesis has been published,
that it depended upon fresh-water springs at the bottom of the ocean, and such an
opinion might have some chance as long as we only had few observations ; but now we
have such a number of observations spread over a vast extent of the ocean, that it
appears to be quite impossible to explain it by springs of fresh water, which of course
must be more frequent and more powerful near the land, from which they have their
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
239
origin. Observation, however, shows the reverse ; near the shores the water is either
uniform throughout its whole depth, or the quantity of salt increases with the depth.
The next question is whether we can find a similar distribution in the other parts of the
ocean. As to the southern portion of the Atlantic, there occurs such a confused distri-
bution of the quantity of salt in the different depths at the same place, that we are not
able as yet to draw any conclusions from it, but must wait for more copious observations.
, As to the other parts of the ocean, I have only very few observations from the sea
between Africa and the Aleutic Islands; but these few observations do not show any
regularity, or at all events seem more to incline to an increase of the quantity of salt
with the increasing depth. The geographical distribution between land and sea is, how-
ever, quite different in this large part of the ocean. While a strong polar current from
Baffin’s Bay pours its cold and less saline waters into the North Atlantic Sea, the large
mass of Asia prevents any north polar current from reaching the south Asiatic sea, into
which the numerous great rivers of Asia send vast quantities of warm fresh water.
As to the south polar currents, we know very little about their influence upon the
salinity of the southern ocean; but in Sir James Ross’s ‘Voyage’ (vol. ii. p. 133) there
is an observation upon the different specific gravity in different depths, which indicates a
state of things similar to that in the North Atlantic Ocean. His observations are these :
— “At 39° 16' S. lat., 177° 2' W. long., the specific gravity of the surface-water 1-0274,
at 150 fathoms 1-0272, and at 450 fathoms 1-0268, all tried at the temperature of 60° F.,
and showing that the water beneath was specifically lighter than that of the surface when
brought to the same temperature ; our almost daily experiments confirmed these results ” *.
The ’principal currents of the Atlantic , the Equatorial current , the Gulf -stream ,
and the East Greenland current.
These three currents are in fact only the same ; they begin, as is well known, in the
Bay of Benin, under the Equator, and the main current runs straight to the west over
the Atlantic to Cape Roque, on the east coast of South America. I certainly shall not
try to lessen the weight of the arguments which assign the cause of this equatorial
current to the rotatory motion of the earth, but I will only give some remarks as to
other influences that act to the same effect.
If we compare the quantity of salt which is found in sea-water in the region between
* To compare these observations of specific gravity with the quantity of salt in different depths, which I
have mentioned in the former part of this paper, I shall here refer to some experiments which I have made to
obtain a ratio by which I could compute the quantity of salts in the sea-water from the specific gravity, and
vice versa. I have compared, in thirteen specimens of sea-water, the specific gravity with the quantity of
chlorine which the water contained, between 13°-75 C. (56°-75 F.) and 18°-8 C. (65°-8 F.). It was found that
a unit in the fourth decimal place of the specific gravity of sea-water, measured by the hydrometer, is equal to
l.ooY.ooo chlorine, the minimum being 66, the maximum 76. To find what quantity of salt corresponds to
the specific gravity of the surface-water, as determined by Sir James Ross to he 1-0274, we must multiply 274
by 71, which gives 19-454 chlorine in the sea-water, and that number being multiplied by the general coefft-'
cient 1-812, gives 35-251 per 1000 salt for the water from the surface. According to the same computation the
sea-water from 150 fathoms contained 34-993 per 1000 salt, and that from 450 fathoms 34-478 per 1000 salt.
240
PEOFESSOE FOECHIIAMMEE ON THE COMPOSITION
5° N. lat. and 5° S. lat. with those between 5° and 20° to the North and of 5° to 30° to
the South, we find the interesting fact that the water flowing in the vicinity of the
Equator contains less salt than that which flows both to the north and to the south of
it. For the equatorial region (5° S. to 5° N.) the mean of six observations is 35*575
per 1000 ; or if we leave out a sample from Sir James Ross, from 150 fathoms’ depth
(that from the surface is wanting), it is 35 ‘520. From 5° to 20° N. the mean of eight
analyses is 36 ’2 79, and from 5° to 30° S. the mean of six analyses is 36*631 per 1000.
This difference is still more striking on comparing the salinity of the equatorial region
with that of the northern Atlantic region (second region), whose mean is 35*932 per
1000 salt. It deserves further attention, that the maximum of the equatorial region is
below the mean of its neighbours both to the south and to the north. It appears to me
that this curious fact can be explained only by the vast quantity of fresh water which
the Niger, the Ogaway, and a number of other West African rivers carry in this region
into the sea, which all gets into the equatorial current, and moves to the westward. It
is evident that this warm water must increase its relative quantity of salt by evaporation
during its motion across the Atlantic, and a comparison of the analyses of the single
samples of the water from the equatorial current shows that this effect really takes
place. The easternmost sample contains the minimum, with 34*238 per 1000, and the
two westernmost samples contain the greatest quantity of salt, with 36*084. Thus the
equatorial current appears as a continuation of the large West African rivers of the
equatorial zone, which dilute the sea-water of the equatorial region with about 8 per
cent, of fresh water, and thus counteract the great evaporation. While the equatorial
current continues its course along the north-east coast of South America, it receives and
carries with it the waters of the Paranahyba, the Araguai, the Amazon river, the Esse-
quibo, the Orinoco, and numerous smaller rivers of the north coast of South America ;
but though I have no observations from this part of the current*, the fact is shown by
three observations from the sea in the neighbourhood of the Danish islands of St. Croix
* [When my remarks on the equatorial current between Cape Eoque and the West Indian islands were
written, I was not aware of the very interesting observations which General Sabine made in 1822, on the
influence of the water of the Amazon river on that of the Equatorial current. I shall now insert them here,
their hearing being in the same way as my deficient observations.
In 5° 8' N. lat. and 50° 28' W. long, a distinct line of separation was observed between the pure blue water
of the ocean and the discoloured water mixed with that from the Amazon river, the mouth of which was about
300 miles distant. The blue water had a specific gravity of 1-0262, which according to my calculation (p. 37)
is =33-672 per 1000 salt, while the water on the other side of the line of separation was 1-0204=26-345 per
1000 salt; further on, under the influence of the river, it was 1-0185=23-800 per 1000 salt. But the river
water kept on the surface and in a depth of 126 feet, the specific gravity was l-0262(= 33-672 per 1000 salt)..
In 7° 1' N. lat. and 52° 38'-5 W. long, the specific gravity was 1-0248=31-905 per 1000 salt, and in 120 feet
depth again 1-0262 specific gravity.
In 7° 5' N. lat. and 53° 30' W. long, it was 1-0253=32-549 per 1000 salt.
In the Gulf of Paria, off the mouth of the Orinoco, the specific gravity was 1-0204=26-345 per 1000 salt, and
in crossing one of the branches of the- river itself the specific gravity was found to be only 1-0064=8-234 per
1000 salt. See ‘An Account of Experiments to determine the Figure of the Earth, by Edwakd Sabine. London,
1825.’— G, F., April, 1865.]
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
241
and St. Thomas, whose mean salinity is 35*7 per 1000 ; while two degrees more to the
north the mean of two observations is 36*7, which seems to be the normal salinity of
the West Indian Sea. In the Caribbean Sea, where the Magdalene river gives a new
quantity of fresh water, the sea contains on the surface, according to one observation,
36*104 per 1000 salt. I have unfortunately no observation from the Mexican Gulf,
nor from the beginning of the Gulf-stream, where it leaves the Mexican Gulf, but to
the north of the Bermudas it contains only 35*883 per 1000 salt, about the same quan-
tity which the equatorial current contains between 20° and 30° W. longitude. From
that place the salt of the Gulf-stream increases constantly during its course towards the
north-east, viz. 36*105 per 1000, 36*283 per 1000. In 43° 26' N.lat. and 44° 19' W. long.,
about 16° of longitude to the east of the southern mouth of the St. Lawrence, between
Nova Scotia and Newfoundland, it sinks suddenly to 33*854 per 1000, and rises from
thence slowly in its course towards the east to 34*102 and 35*597, until, midway between
Newfoundland and the south-western cape of Great Britain, it has risen to 35*896 per
1000, a quantity of salt which diminishes very little in the whole North Atlantic Ocean
between Scotland and Iceland. During this whole long course, from the Bay of Benin
to Spitzbergen, this remarkable current shows a constant oscillation between the diluting
influence of the large rivers and the evaporation occasioned by the high temperature of
the current.
Now we shall try to trace its further progress. I have always thought that the East
Greenland current was of polar origin, and that it carried the waters from the large
opening between Spitzbergen and the northernmost coast of Greenland into Davis’s
Straits, where it turns and mixes its waters with the polar current that comes from the
North American polar sea through Lancaster Sound, and the numerous other sounds
that connect Baffin's Bay with the American polar sea, but I never had an opportunity
of making comparative analyses of the water from that but seldom visited part of the
ocean. Colonel Schaffner had the kindness on his voyage between the eastern part of
Iceland and the south part of Greenland to take a number of samples, which I have
analyzed, and the result of which will be found in my fourth region, the East Green-
land current. The mean of twelve observations of water, taken for the greatest part by
Colonel Schaffjster (three by Captain Gram), is 35*278 per 1000 salt, where one analysis
of water taken in the ice-pack is left out, being no fair sample of sea-water from that
region. In comparing this mean number with that of the North Atlantic Ocean (35*391),
there will hardly be found any difference in the quantity of salt the two contain ; while
there is a great difference between these and the real polar current of Baffin’s Bay,
which is 33*281 per 1000, or of the Patagonian polar current (33*966). I think we may
infer from this fact, that the East Greenland current is a returning branch of the Gulf-
stream, and that the east coast of Greenland proportionally gives very few icebergs and
very little glacial water to the sea. For comparison’s sake I shall mention here that the
sea about midway between Norway and Spitzbergen contains 35*222 per 1000. I found
the water taken on the south side of that island to contain 35*416 per 1000, while that
242
PROFESSOR FORCHHAMMER ON THE COMPOSITION
on the north side of Spitzbergen contained 33-623 per 1000. The last-mentioned sample
seems to be real polar water, while all the water that flows between Norway, Spitzbergen,
Iceland, and the east coast of Greenland partakes of the nature of the Gulf-stream.
Besides the reasons just mentioned for considering the East Greenland current to be
a returning branch of the Gulf-stream, reasons which are deduced from the quantity of
salt which the water contains, there are other reasons which lead to the same result. It
is well known that the Gulf-stream brings tropical fruits from America to the coast of
Norway, and it has once brought a river-vessel loaded with mahogany to the coast of the
Faroe Islands. It is likewise known that similar fruits to those which are found on the
Norwegian shores are carried by the sea to the coast of Iceland, and principally to its
north and east coasts, where they only could get if the Gulf-stream turns between Spitz-
bergen and Iceland, and thus runs between Iceland and Greenland towards the south-
west. It would be difficult to explain how a polar current could bring tropical fruit to
the north coast of Iceland.
On the west coast of Greenland the south-easterly wind brings in winter a mild tem-
perature, and this fact is so generally known in the Danish colonies of Greenland, that
many of the colonists are convinced that there are volcanos in the interior of that
snow-clad land. The temperature which this current, that in winter and spring is full
of drifting ice (not icebergs), communicates, can of course not be above freezing-point,
hut that temperature is mild, when the general temperature in winter is 8°, 10°, or 12° R.
below the freezing-point. All these facts together leave hardly any doubt in my mind
that it is the Gulf-stream which runs along the east coast of Greenland, and at last in
Davis’s Straits mixes its waters with the polar current from Baffin’s Bay. In its course
towards the south it meets the main part of the Gulf-stream at Newfoundland, where it
partly mixes with it to begin its circulation anew, partly dives under it, and runs as a
ground stream as far as the Equator. In a similar way the southern branch of the Gulf-
stream, which goes parallel to the western shores of South Europe and North Africa,
joins the equatorial current at its beginning in the Bay of Benin, and begins also its
circulation anew.
Chemical Decomposition in Sea-water.
If we consider the almost uniform composition of sea-water in the different parts of
the ocean, such as they are represented by comparing the salts with the quantity of
chlorine as unity, and thus avoiding the influence of the different quantities of water
in which they are dissolved, we might be inclined to suppose the salts of sea-water to
be in chemical combination with each other, and to form a compound salt with definite
proportions. This is however not the case, and sea-water is not more a chemical com-
pound than the atmospheric air, and the steadiness of the quantity of the different sub-
stances depends partly upon the enormous mass of the water of the ocean, compared
to which all changes disappear, partly upon the constant motion which current and
wind occasion. In the bays and those parts of the sea which only have narrow sounds
that connect them with the main ocean, where therefore the general motion of the sea
4
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
243
cannot have that influence it has in the open ocean, we observe differences which show
the influence of the land upon the constituent parts of the sea-water. This want of
chemical combination between different salts will become more evident when, instead
of comparing their different quantities, we compare the relative number of their equi-
valents. The mean quantity of the different substances in the whole ocean, as deduced
from the mean of regions I., II., III., IV., V., XI., XII., XIII, XIV, XV, XVI,
XVII, is in 1000 parts of sea-water, —
Chlorine.
18-999
Sulphuric acid.
2-258
Lime. Potash. Magnesia.
0-556 0-367* 11-03
All salts.
34-404
Coefficient.
1-811
Sulphuric acid.
11-88
Chlorine =100.
Lime. Potash. Magnesia.
2-93 1-87* 11-03
All salts.
181-1
Chlorine.
429
Proportion of Equivalents.
Sulphuric acid. Lime. Potash.
45 16 6
Magnesia.
82.
There is one question which deserves a closer examination, viz. how the salts that
now constitute the water of the sea came into it X Is it the land that forms the sea, or
is it the sea that makes the land X Are the salts that now are found in sea-water washed
out of the land by the atmospheric water X Has the sea existed from the beginning of
the earth X and has it slowly but continually given its elements to form the land X
To try to give an answer to these most important questions, let us suppose that any
river, for instance the Rhine, had its outlet into a valley with no communication with
the sea, it would be filled with water until its surface was so great, that the annual
evaporation was equal to the quantity of water which the river carried into it ; then there
would be a physical equilibrium but no chemical, because all the water that was carried
into the lake would contain different mineral substances, which the rain-water had dis-
solved from the country which the river drains, while the loss by evaporation would be
pure water. The quantity of saline substances in the lake would constantly go on
increasing until chemical changes would occasion the precipitation of different salts.
By comparing the chemical constitution of the water of the Rhine, we might form an
idea of the different elements contained in the water of this lake. We should find that
among the bases the lime was prevailing, and next to it the magnesia, next to it the
soda, the iron, the manganese, the alumina, and potash. Of acids the carbonic would
be prevailing, and next to it the sulphuric, the muriatic (chlorine), and the silicic.
Now all these substances are found in sea- water, but the proportions are quite different.
* The potash which I have mentioned here represents in fact not the mean of all the observations in the
great ocean, but only the mean of a number of determinations for the northern part of the Atlantic, my older
observations on the quantity of potash in the other parts of the ocean being not exact enough. This quantity
of potash differs most probably very little from the real mean.
MDCCCLXV. 2 L
244
PEOFESSOE FOECHHAMMEE ON THE COMPOSITION
The ocean is in fact such a lake, into which all the rivers carry what they have dissolved
from the land, and from which pure water evaporates ; and whatever we think about
the constitution of the primitive ocean, this effect of the rivers, which has lasted for
thousands of years, must have had an influence upon the sea. Why do we not observe
a greater influence of the rivers 1 Why does not lime, the prevailing base of river-water,
occur in a greater proportion in the water of the ocean 1 In all river-water the number
of equivalents of sulphuric acid is much smaller than that of lime, and yet we find in
sea-water about three equivalents sulphuric acid to one of lime. There must thus be in
sea- water a constantly acting cause that deprives it again of the lime which the rivers
furnish, and we find it in the shell fishes, the corals, the bryozoa, and all the other
animals which deposit carbonate of lime. From the proportion between sulphuric acid
and lime in river-water and in sea-water, it is evident that these animals are able not only
to deprive the water of its carbonate of lime, of which sea-water contains very little, but
that they also must decompose the sulphate of lime, a decomposition which probably
depends upon the carbonate of ammonia which is formed by the vital process of these
animals. I have shown that a salt of ammonia occurs in sea-water, certainly in small
quantities, which however does not signify much, since the ammonia is constantly
absorbed by the sea-weeds. Thus it is a chemical action of small animals which con-
stantly deprives the sea of its excess of lime.
Next to the lime we must consider the silica, which is a constant constituent of river-
water, and the immense quantity of diatomacese, of infusoria, and sponges will account for
the small quantity of it at any given time in sea-water. I shall name next the sulphuric
acid. All the shells of shell fishes, all the carbonate of lime in the corals and bryozoa
contain some sulphate of lime, about one per cent, or less, but all the sea-weeds attract
a great quantity of sulphates, which by the putrefaction of the plants are changed into
sulphurets ; and the sulphurets give again their sulphur to the iron, both that which is
dissolved in sea-water, and that which in the form of oxide, combined with clay and
other earths, is mechanically suspended in the water of the sea, principally near the
shores. Thus the sulphur is made insoluble and disappears from the brine. The mag-
nesia enters in a small quantity into the shells and corals, but only a small quantity is
thus abstracted from sea-water, and at last the soda and muriatic acid or chlorine form,
as far as we know, by the pure chemical or organico-chemical action that takes place
in the sea, no insoluble compound. Thus the quantity of the different elements in sea-
water is not proportional to the quantity of elements which river-water pours into
the sea, but inversely proportional to the facility with which the elements in sea-water
are made insoluble by general chemical or organo-chemical actions in the sea ; and we
may well infer that the chemical composition of the water of the ocean in a great part
is owing to the influence which general and organo-chemical decomposition has upon it,
whatever may have been the composition of the primitive ocean. I shall, however, not
dwell any longer on this side of the question, which deserves a much more detailed
representation than I can give it here.
OF SEA- WATER IN THE DIEEEEENT PARTS OF THE OCEAN.
245
There is a more special decomposition of sea-water, which takes place exceptionally,
but these exceptions are very frequent. They depend upon the organic beings that live
in the sea, die, and decay in the sea, and are finally dissolved. Of these substances
that have their origin from organic beings, I have already named ammonia ; but there
are other substances of organic origin, probably of a more complicated nature, which I
have observed in the following way. If we pour one or two drops of a solution of
hypermanganate of potash into fresh sea-water, which has no smell of sulphuretted
hydrogen, we shall after a short time observe a change in the colour of the liquid, but it
is hardly more than the first drop that is decomposed so soon after it has been mixed
with sea-water. The next decomposition goes slower, and is only finished after the
liquid has been boiled for some time. Now if we pour hypermanganate of potash into
a very diluted solution of ammonia, it will be completely decomposed by warming the
mixture to a slight degree. I suppose that the first action upon the hypermanganate
depends upon the ammonia in sea-water, and the next, which is slower and requires
boiling and a longer time of action, depends probably upon the other products of spon-
taneous decomposition of organic matter. Coinciding with these observations is the
experience that sea-water taken near the surface decomposes a smaller quantity of
hypermanganate than that which is taken from the depth. If it was ammonia that
produced the decomposition, there is no reason why there should be less of it near the
surface than in deep water, since it being combined with a strong acid (either sulphuric
or muriatic) neither could be volatilized nor oxidized. If it was organic matter, it would
be oxidized near the surface, on account of the absorbed oxygen of the atmosphere.
When this organic matter increases in sea-water near the shores, or at the mouth of
rivers, it will cause a real putrefaction, and attack the sulphates, converting them into
sulphurets, which again are decomposed by the carbonic acid formed from the organic
substances at the expense of the oxygen of the sulphuric acid. This sulphuretted
hydrogen gets free, the carbonic acid will precipitate lime, and a loss of sulphuric acid
by fermentation will always occasion a loss of lime in sea-water. Putrefaction seldom
decomposes more than a small quantity of the sulphuric acid present in sea-water, and
even where it seems to have been very powerful, not one-third part of the sulphuric
acid has been destroyed. While thus a portion of the sulphates always remains unde-
composed, there also seems always to remain a portion of the organic matter unoxidized.
The sulphuretted hydrogen acts instantaneously upon hypermanganates, but when all
smell of sulphuretted hydrogen has disappeared, there still remains some substance in
putrefied sea-water which bleaches the hypermanganates when the water is boiled. It
may be one of the lower oxides of sulphur, or it may be that the organic substance was
not fully oxidized.
There is still one general effect of the organic substances dissolved in sea-water, that
all iron is reduced from peroxide to protoxide, all mud from the deeper parts of the sea
is dark coloured, either grey, bluish, or green. All Sir James Ross’s deep soundings
brought blue or green mud or sand to the surface.
2 L 2
426
PROFESSOR FORCHHAMMER ON THE COMPOSITION
In the following Tables the sulphuric acid, lime, magnesia, and potash are given both
in parts per 1000 sea-water, and referred to chlorine as 100. The latter numbers are
distinguished by being enclosed in parentheses.
First Region. — From the Equator to 30° N. lat.
Chlorine.
Sulphuric
Lime.
Magnesia.
All salts
together.
Coefficient.
acid.
1. Sir James Ross, June 11, 1843. 1
19-757
2-303
0-584
2-333
35-737
1-801
N. lat. 1° 10', W. long. 25° 54' J
(11-66)
(2-96)
(11-81)
2. Captain Irminger, September 9, 1 847. \
19-584
2-315
0-765
2-179
35-803
1-803
Tocorady Bay, Guinea, 1 mile from the land... J
(11-66)
(3-85)
(10-99)
3. Captain Irminger, September 7? 1847- 1
N. lat. 4° 10', W. long. 5° 36' /
19-014
2*224
0-660
2-163
24-283
1-803
20-070
(11-64)
(3-47)
(11-37)
36-327
4. Sir James Ross, July 6, 1843. 1
N. lat. 6° 43', W. long. 27° 4' /
f>. Valkyrie, February 3, 1848.
19-766
2-415
0-568
2-117
35-941
1-818
N. lat. 10°, W. long. 24° 19£' J
(12-22)
(2-87)
(10-71)
6. Sir James Ross, July 11, 1843. 1
N. lat. 11° 43', W. long. 25° 6' J
20-035
36-263
7. Sir James Ross, July 22, 1843. 1
20-114
2-343
0-619
2-315
36-195
1*800
N. lat. 12° 36', W. long. 25° 33' J
(11-39)
(3-08)
(11-21)
8. Sir James Ross, July 25, 1843. 1
N. lat. 15° 38', W. long. 27° 15' /
20-081
36-347
9. Sir James Ross, July 26, 1843. 1
N. lat. 16° 57', W. long. 29° /
20-186
36-537
10. Sir James Ross, July 27, 1843. 1
N. lat. 18° 6', W. long. 29° 56' /
20-429
36-976
11. Ornen, October 19, 1846. 1
19-818
2-376
0-567
2-123
35-775
1-805
N. lat. 19° 20', W. long. 65° 28' /
(11-99)
(2-86)
(10-76)
12. Valkyrie, January 28, 1848. 1
N. lat. 24° 13', W. long. 23° 1 1' J
20-898
2-446
0-595
2-280
37-908
1-814
(11-70)
(2-85)
(10-91)
13. Captain von Dockum, July 17, 1845. 1
19-650
2-309
0-567
2-236
35-732
1-819
Between the Islands St. Croix and St. Thomas /
(11-75)
(2-89)
(11-36)
14. Captain von Dockum, July 18, 1845. 1
17*798
2-304
0-426
2-195
35-769
1-807
Likewise between the two islands J
(11-64)
(2-15)
(11-69)
15. Ornen, October 23, 1846. 1
20-320
2-423
0-602
2-208
36-784
1-810
N. lat. 22° 43', W. long. 65° 12' J
(11-92)
2-344
(2-96)
0-554
(10-87)
2-164
16. Captain von Dockum, Julv 29, 1845. 1
20-145
36-508
1-812
N. lat. 22° 30', W. long. 69° 1 0' /
(11-64)
(2-75)
(10-74)
17- Captain Irminger, March 17, 1849. 1
20-302
2-450
0-620
2-302
36-736
1-809
N. lat. 25° 4', W. long. 65° 40' j
(12-07)
(3-05)
(11-34)
18. Captain von Dockum, July 30, 1845. 1
N. lat. 23° 26', W. long. 64° 8' /
20-291
2-207
(10-88)
2-418
0-606
(2-99)
0-600
2-251
(11-09)
2-217
36-352
1*792
19. Ornen, October 28, 1846. 1
20-389
36-838
1-807
N. lat. 29° 27', W. long. 60° 1' /
(11-86)
(2-94)
(10-87)
Mean <|
' 20-034
2-348
0-595
2-220
36-253
1-810
(11-75)
(2-98)
(11-11)
Maximum j
: 20-898
2-450
(12-22)
0*765
(3-85)
2-333
(11-81)
37-908
1-819
Minimum j
■ 19-014
2-207
(10-88)
0-426
(2-15)
2-117
(10-71)
34-283
1-792
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
247
Second Region. — The Atlantic between 30° N. lat. and a line from the northernmost
point of Scotland to the north point of Newfoundland.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts
together.
Coefficient.
1. Captain von Dockum, August 3, 1843. ]
N. lat. 31° 51', W. long. 67° 23' f
20*159
2*449
0*607
2*460
36*480
1*810
(12*15)
(3*01)
(12*20)
1
2. Captain von Dockum, August 3, 1843. ]
N. lat. 32°„52', W. long. 68°. To the west of l
the Bermudas 1
20*064
2*489
(12*15)
0*566
(2*82)
2*062
(10*28)
36*635
1*826 |
3. Captain Schulz, September 28, I860. 1
20*160
2*302
0*610
2*134
36*391
1*805
Straits of Gibraltar j
(11*42)
(3*03)
(10*59)
4. Ornen, November 5, 1846.
20*080
2*398
0*600
2*250
36*304
1*808
N. lat. 36° 13', W. long. 55° 7' |
(11*94)
(2*98)
(11*20)
5. Captain von Dockum, August 6, 1843. |
N. lat. 36° 52', W. long. 66° 38'. North from L
19*890
2*336
0*595
2*299
35*883
1*804
Bermudas in the Gulf-stream J
(11*74)
(2*99)
(11*66)
6. Ornen, November 7, 1846. |
20*103
2*518
0*643
2*177
36*643
1*823
N. Iat. 37° 5', W. long. 48° 24' j
7. Captain von Dockum, August 7, 1843. 1
N. lat. 37° 24', W. long. 6l° 8' j
(12*52)
(3*15)
(10*83)
19*943
2*374
(11*90)
2*557
0*595
(2*98)
0*689
2*284
(11*45)
2*260
36*105
1*810
8. Ornen, November 9, 1846. 1
20*247
36*928
1*824
N. lat. 38° 18', W. long. 43° 2' J
(12*63)
(3*40)
(11*16)
9. Captain von Dockum, August 13, 1843. 1
20*063
2*432
0*588
2*208
36*283
1*808
N. lat. 39° 39', W. long. 55° 16' J
(12*12)
(2*93)
(11*01)
10. Captain von Dockum, August 13, 1843. 1
N. lat. 40° 21', W. long. 54° 15' J
20*098
2*425
0*606
2*391
36*360
1*809
(12*07)
(3*02)
(11*90)
11. Ornen, November 11, 1846. j
N. lat. 40° 53', W. long. 36° 23'. S.W. from l
the Newfoundland Bank J
20*062
2*427
(12*10)
0*718
(3*58)
3*123
(10*58)
36*389
1*814
12. Captain von Dockum, August 17, 1843. 1
18*685
2*208
0*534
2*081
33*854
1*812
N. lat. 43° 26', W. long. 44° 19' J
(11*82)
(2*86)
(11*14)
13. Captain von Dockum, August 18, 1843. j
N. lat. 44° 33', W. long. 42° 34'. E. from the l
18*842
2*236
0*560
2*079
34*102
1*810
Newfoundland Bank J
(11*87)
(2*97)
(11*03)
14. Omen, November 13, 1846. \
19*890
2*376
0*650
2*154
36*032
1*812
N. lat. 44° 39', W. long. 30° 20' j
(11-95)
(3*27)
(10*83)
15. Ornen, November 15, 1846. 1
19*857
2*400
0*582
2*185
36*010
1*813
N. lat. 46° 22', W. long. 22° 55' J
(12*09)
(2*93)
(11*01)
16. Ornen. \
19*892
2*400
0*586
2*175
36*090
1*814
N. lat. 47° 10', W. long. 18° 45' j
(12*09)
(2*94)
(10*94)
17* Ornen. \
19*722
2*441
0*590
2*166
35*872
1*819
N. lat. 47° 17', W. long. 14° 24' j
(12*38)
(2*99)
(10*98)
18. Captain von Dockum.
N. lat. 47° 17f, W. long. 19° 9' (
19*656
2*346
0*580
2*170
35*625
1*812
(11*94)
(2*95)
(11*04)
36*119
19. Captain von Dockum.
19*915
2*413
0*587
2*172
1*814
N. lat. 47° 18', W. long. 21° 6|' j
(12*12)
2*327
(2*95)
0*583
(10*91)
2*265
20. Captain von Dockum. 1
19*860
35*896
1*808
N. lat. 47° 40', W. long. 32° 7' J
(11*72)
(2*94)
(11*40)
21. Captain Schulz. 1
19*664
2*556
0*589
2*273
35*922
1*823
N. lat. 47° 45', W. long. 9° 30' J
(13*01)
(2*99)
(11*57)
22. Captain von Dockum.
N. lat. 47° 50’, W. long. 33° 50' j
19*749
2*320
0*601
2*183
35*597
1*803
(11*75)
(3*04)
(11*06)
23. Ornen. 1
19*882
2*393
0*726
2*077
36*093
1*815
N. lat. 48° 10', W. long. 9° 35' J
(12*03)
(3*65)
(10*45)
24. Captain von Dockum. 1
N. lat. 50° 3', W. long. 11° 6' J
25. Porcupine, mean of 5 analyses of surface- )
water taken between 51° 9' and 55° 32’ N. 1
19*691
2*336
(11*86)
0*572
(2*90)
2*208
(11*21)
35*570
1*806
19*662
2*342
0*566
2*205
35*613
1*811
lat., and 12° 11' and 13° 59' W. long J
Mean j
19*828
2*389
0*607
2*201
35*932
1*812
(12*05)
(3*07)
(11*10)
36*927
1*826
Maximum J
20*247
2*557
(13*01)
0*726
(3*65)
2*460
(12*20)
Minimum j
18*685
2*208
0*534
2*062
33*854
1*791 |
(11*08)
(2*82)
(10*28)
248
PROFESSOR FORCHHAMMER ON THE COMPOSITION
Third Region. — The northern part of the Atlantic, between the northern boundary of
the second region, and a line from the south-west point of Iceland to Sandwich
Bay, Labrador.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Lieutenant Skibsted, 1844. J
19-287
2-254
0-488
2-136
34-831
1-806
W. long. 3° 15', N. lat. 60° 25' {
(11-68)
(2-51)
(11-07)
2. Captain Paludan, May 8, 1845. j
W. long. 5° 19', N. lat. 60° 94' |
19-485
2-289
0-568
2-146
35-223
1-808
(11-75)
(2-92)
(11-01)
3. Captain Gram, May 5, 1845. J
W. long. 7° 52', N. lat. 59° 50' 1
19-671
2-342
0-592
2-210
35-576
1-809
(11-91)
(3-01)
(11-23)
4. Captain Gram, 1845. j
W. long. 7° 20', N. lat. 60° 20' 1
19-619
2-296
0-587
1-820
35-387
1-814
(11-70)
(2-99)
(9-28)
6. Captain Gram, May 7, 1845. J
W. long. 14° 7'» N. lat. 60° 9' 1
19-620
2-306
0-581
2-189
35-493
1-809
(11-75)
(2-96)
(11-16)
6. Captain Gram, 1845.
W. long. 16° 32', N. lat. 61° 1
19-558
2-285
0-581
2-330
35-281
1-804
(11-68)
(2-97)
(11-91)
7. Taken by an Unknown. J
20-185
2-336
0-699
2-241
36-480
1-807
W. long. 20£°, N. lat. 55|° 1
(H-59)
(3-31)
(11-10)
8. Captain Gram, May 10, 1845. J
W. long. 20° 30', N. lat. 59° 58' 1
19-560
2-294
0-584
2-214
35-291
1-804
(11-73)
(2-99)
(11-32)
9- Captain Paludan, Mav 10, 1845. J
19-466
2-343
0-576
2-117
35-348
1-816
W. long. 23° 3', N. lat. 62° 15' ' 1
(12-04)
(2-96)
(10-88)
10. Captain Gram, May 15, 1845. J
W. long. 26° 23', N. lat. 59° 50' 1
19-545
2-330
0-583
2-190
35-397
1-811
(11-92)
(2-98)
(11-20)
11. Captain Gram. j
19-579
2-277
0-570
2-196
35-399
1-808
W. long. 26° 37', N. lat. 60° 30’ 1
(11-63)
(2-91)
(11-22)
12. Captain Gram, September 1, 1845. j
W. long. 36°, N. lat. 58° 58' \
19-386
2-365
0-578
2-135
34-990
1-805
(12-20)
(2-98)
(11-01)
Mean j
19-581
2-310
0-528
2-160
35-391
1-808
(11-80)
(2-97)
(11-03)
Maximum j
20-185
2-385
(12-50)
0-669
(3-31)
2-330
(11-98)
36-480
1-811
Minimum j
19-287
2-254
(11-59)
0-488
(2-51)
1-820
(9-28)
34-831
1-804
OF SEA-WATEE IN THE DIFFEEENT PAETS OF THE OCEAN.
249
Fourth Kegion. — The East Greenland Current.
Chlorine.
Sulphuric
acid.
Sulphuric
acid.
Chlorine
= 100.
All salts.
Coefficient
1-813.
1. Colonel Schaffner, September 2, I860. 1
Faxefjord, Iceland.
W. long. 24° 1' 30", N. lat. 64° 16' 11' J
2. Colonel Schaffner, September 3,1860. ]
W. long. 26° 24', N. lat. 64° 30' J
3. Colonel Schaffner, September 6, I860. ]
W. long. 27° 8', N. lat. 64° 15' J
4. Colonel Schaffner, September 8, I860. ]
W. long. 29° 36', N. lat. 63° 25' J
5. Colonel Schaffner, September 9, I860. ]
W. long. 27° 34' 35", N. lat. 63° 34' 30" J
6. Colonel Schaffner, September 9, I860. 1
W. long. 33° 22' 45", N. lat. 63° 24' i
7. Colonel Schaffner, September 10, I860, i
W. long. 37° 31' 30", N. lat. 62° 47'
8. Colonel Schaffner, September 11, I860.
W. long. 38° 18', N. lat. 62° 16' 34"
9. Colonel Schaffner, September 13, I860, j
In ice pack.
W. long. 41° 45', N. lat. 60° 48' 40"* j
10. Colonel Schaffner, September 14, I860.
W. long. 40° 56', N. lat. 59° 49'
11. Captain Gram, May 18, 1845.
W. long. 33° 32', N. lat. 60° 23'*
12. Captain Gram, May 20, 1845.
W. long. 39° 4', N. lat. 59° 26'*
13. Captain Gram, May 22, 1845.
W. long. 46° 1', N. lat. 57° 57'*
19*517
19-616
19-579
19-518
19-545
19442
19-491
19-469
16-831
19-136
19-512
19-306
19-365
2-360
2-420
2-382
2-293
2-300
2-341
2-291
2-309
1- 995
2- 252
2-385
2-310
2-305
12-09
12-34
12-17
11-75
11- 77
12- 04
11-75
11-86
11-85
11- 75
12- 22
11-97
11-90
35-385
35-563
35-495
35-386
35-435
35-248
35-337
35-297
30-515
34- 694
35- 390
35-067
35-038
Mean
19*458
2-329
11-97
35-278
Maximum
19-616
2-420
12-34
35-563
Minimum
19-136
2-252
11-75
34-694
* This observation in the pack is not used for determining the means. Observations 11, 12, 13 are complete
analyses with a coefficient 1-814, 1-816, and 1-809 ; mean 1-813. This mean coefficient is used for calculating
the quantity of all salts in Colonel Schafkstek’s samples, where there was not enough for complete analysis.
250
PROFESSOR FORCHHAMMER ON THE COMPOSITION
Fifth Region. — Davis Straits and Baffin’s Bay.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Captain Gram, May 26, 1845.
N. lat. 60° 32', W. long. 53° 11'
19*010
2*283
0*550
2*115
34*414
1*810
(12*01)
(2*89)
(11*13)
2. Captain Gram, June 2, 1845.
N. lat. 62° 8', close to the island ved Fre-
derickshaab
18*317
2*161
(11*80)
0*551
(301)
2*036
(11*12)
33*109
1*808
3. Captain Gram, June 12, 1845.
Close to the Killiksut Islands near Nanarsuit
(about N. lat. 60°)
18*386
2*144
(11*66)
0*546
(2*97)
2*018
(10*98)
33*190
1*806
4. Dr. Kaiser, September 5, 1845.
18*251
2*131
0*455
2*140
32*926
1-804
N. lat. 64° 41', Davis Straits j
(11*68)
2*187
(12*27)
(2*49)
0*496
(2*78)
(11*73)
2*005
(11*25)
5. Dr. Kaiser, September 4, 1845.
N. lat. 66° 58', about 30 English sea-miles
from Greenland
17*818
32*304
1*813
6. Dr. Kaiser, August 30, 1845.
N. lat. 68° 43', W. long. 52° 45', harbour of
18*325
2*238
(12*21)
0*495
(2*70)
2*080
(11*35)
33*187
1*811
S7. Dr. Kaiser, September 3, 1845.
8 sea-miles from Godhavn, Disco (about
N. lat. 69° 50 )
18*401
2*255
(12*25)
0*455
(2*47)
2*008
(10*91)
33*446
1*818
8. Dr. Rink, July 5, 1849.
N. lat. 69° 45', 24 English sea-miles W. from
Disco
18*524
2*268
(12*24)
0*530
(2*86)
2*109
(11*39)
33-595
1*814
Mean -
r
18*379
2*208
0*510
2*064
32*281
1*811
(12*01)
(2*77)
(11*23)
Maximum
19*010
17*818
12*27
11*66
3*01
11*73
10*91
34*414
1*818
Minimum
2*47
32*304
1*804
Sixth Region. — The North Sea.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. 1844. 1
18*772
2*312
0*488
2-128
34*302
1*827
Between the Orkneys and Stavanger, in Norway I
i
(12*31)
(2*59)
(11*33)
2. 1844.
1
18-278
2*223
0-455
2*192
33*294
1*822
S.W. of Egernsund. Norway J
b
(12*14)
(2-49)
(11*98)
3. Captain vonDockum, September 16, 1845.^
In the Hooft in the deep channel near the
Galloppers
19*282
2-351
(12-19)
0*560
(2*90)
2*166
(11*23)
35*041
1-817
4 Captain von Dockum, September 18, 1845.
About forty-five English sea-miles W. from
the lighthouse of Hanstholm
i
r
17*127
2-079
(12*09)
0*548
(3*19)
1*929
(11*26)
31*095
1*815
5. Captain von Dockum, September 18, 1845. ]
L
18*131
2-141
0*565
2*037
32*674 |
1*802
Skagerack, between Hirtshals and the Skau. J
1“
(11*81)
(3-12)
(11*23)
6. Back, S. Heligoland.
Analysis from Erdmanns Journal, Bd. 34,
P- 185 J
i
16*830
2-008
(11*93)
0*485
(2*88)
1*866
(11-09)
30*530
1*814
Mean
r
18-070
2*185
0*517
2*053
32*823
1*816
i
(12*09)
(2*86)
(11*25)
Maximum
i
!
19*295
2-351
(12*31)
0*565
(3-19)
2*192
(11*98)
35*041
1*827
Minimum
[
17*127
2-008
(11*77)
0-455
(2*49)
1*866
(11*09)
30*530
1*808
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
251
Seventh Region. — The Kattegat and the Sound.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1845, April. North of Kullen. Current f
6-227
0-776
0-195
0-712
11-341
1-821
from the South j
(12-46)
(3-13)
(11-43)
1845, April. North of the island of Anhalt, j
8-429
1-028
0-257
Current from the South \
(12-09)
(3-02)
1845, June. North of Kullen. Current from j
9*376
1-178
0-393
0-986
17-254
1-840
the North j
(12-57)
(4-19)
(10-51)
1845, June. North of Anhalt. Current from J
9-632
1099
0-298
1-059
17*355
1-802
(11-41)
1 3-10)
(10-99)
1844. Captain Skibsted. Kattegat j
10-077
1-208
(11-54)
0-319
(2-78)
1-253
(11-31)
19-940
1-801
Elsinore. Mean of 134 observations between ]
April 17 and September 11, 1846 j
12-827
23-243
1846, October 4. Copenhagen. Current J
5-966
0-750
0-196
0-620
10-869
1-822
from the South \
(12-57)
(3-28)
(10-39)
Copenhagen. Mean of 7 observations between 1
Q**7 A O
1 K.Q/I 1
March 3 and April 21, 1852 J
O / Z
lO 1
Sandefjord, on the south-east coast of Norway, f
7-740
0-875
0-266
0-818
13-996
1-808
Analyzed by Professor Strecker [
(11-30)
(3-44)
(10-59)
Mean j
8-780
0-998
0-275
0-908
16-230
1-814
(11-94)
(3-29)
(10-86)
Maximum j
12-827
1-2/8
0-393
1-253
23-243
1-840
(12-57)
(4-19)
(11-43)
Minimum j
5-966
0-750
(11-30)
0-195
(2-78)
0-620
(10-39)
10-869
1-801
Eighth Region. — The Baltic.
Chlorine.
Sulphuric
acid.
Lime.
Potash.
Magnesia.
All salts.
Coeffi-
cient.
1. Bellona. N. lat. 58° 27) E. long. 20° ... |
3-863
0-489
(12-65)
0-136
(3-52)
0-066
(1*71)
0-447
(11*57)
7*061
1-828
2. Bellona. Between Hammersh uus, on thelsland f
4-079
0-514
0-126
0-094
0-436
7-481
1-834
of Bornholm, and Sandhammer in Sweden \
(12-60)
(3-09)
(1-99)
(10-69)
3. Bellona. Between Oland and Gothland... j
3-991
0-527
(13-19)
0-137
(3-43)
0-075
(1-88)
0-480
(12-03)
7*319
1-834
4. Bellona. Entrance of the Bay of Finnland |
3-833
0-472
(12-33)
0-145
(3-78)
0-068
(1*77)
0-508
(13-25)
6-933
1-809
5. Bellona. Bay of Finnland, between Hog- f
2-596
0-346
0-092
0-044
0-299
4-763
1-835
land and Tysters \
(13-31)
(3-54)
(1*69)
(11-52)
6. Bellona. Bay of Finnland, between Nervoe J
1-931
0-239
0-076
0-047
0-226
3-552
1-839
and Seskjeld I
(12-38)
(3-91)
(2-43)
(11-70)
7. Bellona. Bay of Finnland, W. from Kron- j
0-331
0-040
0-019
0-023
0-046
0-738
2-230
stadt \
8. Bellona. Bay of Finnland. Merchant- f
0-294
(11-95)
0-044
(5-81)
0-022
(0-69)
0-006
(13-90)
0-046
0-610
2-075
harbour of Kronstadt \
(14-97)
(7*49)
(0-21)
(15-65)
1-836
9. Svartklubben, to the North of Stockholm... j
3-265
0-407
(12-50)
0-132
(4-05)
0-056
(1-72)
0-403
(12-38)
5-919
Mean |
2-687
0-342
0-098
0-053
0-321
4-931
1-835
(100-00)
(12-73)
(3-64)
(1-97)
(11*94)
Maximum |
4-079
0-527
0-145
0-094
0-508
7-481
2-230
(100-00)
(14-97)
(7-49)
(2-43)
(15-65)
0-610
Minimum |
0-294
0-040
0-019
0-006
0-046
1-809
(100-00)
(11*95)
(3-09)
(0-21)
(10-69)
2 M
MDCCCLXV.
252
PROFESSOR FORCHHAMMER ON THE COMPOSITION
Ninth Region. — The Mediterranean.
Chlorine.
Sulphuric
acid.
Lime.
Potash.
Magnesia.
All salts.
Coeffi-
cient.
1. Heimdal, Captain Schulz, Sept. 28, I860.
f
20-160
2-302
0-610
0-415
2-134
36-391
1-805
Straits of Gibraltar
(11-42)
(3-03)
(2-06)
(10-59)
2. Heimdal, Captain Schulz, Sept. 29, I860.
N. lat. 36° 9'. W. Ion*?. 4° 2'
20-235
2-583
(12-8)
0-613
(3-03)
0-345
(1-70)
2-305
(11-39)
37-014
1-829
3. Heimdal, Captain Schulz, Oct. 8, I860.
N. lat. 40° 28', E. long. 1° 48'. Between the
Balearic island and the Spanish coast
>
21-085
2-444
(11-59)
0*641
(3-04)
0-474
(2-25)
2-402
(11-39)
38-058
1-805
4. Heimdal, Captain Schulz, Oct. 10, I860.
21-056
2-542
0-635
0-336
2-356
38-321
1-819
N. lat. 41° 12', E. long. 2° 23'
(12-07)
(3-02)
(1-60)
(11-19)
5. Heimdal, Captain Schulz, Oct. 12, I860.
N. lat. 42° 25', E. long. 6° O'. Between Bar-
celona and Corsica
>
21-217
Q to
T* ^
Cn Or
CO OO
0-629
(2-96)
0-428
(2-03)
2-379
(11-21)
38-290
1-805
6. Heimdal, Captain Schulz, Oct. 20, 1860/)
N. lat. 40° 25', E. long. 11° 43'. Between Sar-
dinia and Naples J
>
21-139
2-652
(12-55)
0-660
(3-12)
0-492
(2-33)
2-322
(10-98)
38-654
1-828
7. Mr. Ennis, 1837. Malta -j
f
20-497
2-471
(12-06)
0-640
(3-12)
0-174
2-074
(10-12)
37-177
1-814
8. Heimdal, Captain Schulz, Nov. 13, 1860/)
N. lat. 36° 10', E. long. 16° 10'. To the East
of Malta j
>■
21-297
2-514
(11-8)
0-686
(3*22)
0-417
(1-96)
2-403
(11-28)
38-541
1-809
9- Heimdal, Captain Schulz, Oct. 23, 1860/)
21-180
2-390
0-597
0-304
2-392
38-013
1-795
N. lat. 37° 20', E. long. 16° 32'. Between Malta
>-
(11-29)
(2-82)
(1-41)
(11-29)
and Greece J
Sulphuretted
hydrogen.
10. Heimdal, Captain Schulz, Oct. 28, I860, i
N.lat.33°34', E. long. 24° 34'. Between Candia<
and the coast of Africa 1
r
21-718
2-517
(11-60)
0-677
(3-12)
0-392
(1-80)
2-447
1(11*27)
39-257
1-808
11. The Mediterranean; exact place unknown. |
20-900
2-433
0-621
0-32
2-223
37*655
Calculated after an analysis in Yiolette and<^
Brom. 432
(11-64)
(2-97)
:(i0-64)
Archambault’s ‘Analyses chimiques’ 1
21-332
Mean \
f
20-889
2-470
0-642
0-372
2-277
37-936
1-815
l
(11-82)
(3-08)
(1-78)
(10-90)
Maximum i.
r
21-718
2-652
0-622
0-492
2-447
(11-39)
39-257
1-829
L
(12-59)
(3-22)
(2-33)
36-391
Minimum <
r
20-160
2-302
0-597
(2-82)
0-174
2-074
(10-12)
1-805
i
(11*42)
Rem auks. — No. 9 is not taken in the calculation of the mean coefficient, on account of the decomposition of
the sulphuric acid, which always lowers the coefficient ; the small quantity of lime in No. 9 depends probably
upon the same decomposition, the sulphate of lime being changed into sulphuret of calcium, which again, by
carbonic acid and water, is decomposed into sulphuretted hydrogen and carbonate of lime, which is precipitated.
OF SEA-WATER IN THE DIFEERENT PARTS OF THE OCEAN.
253
Tenth Region, A. — The Black Sea and the Sea of Assou.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Water from the Black Sea, 50 English f
9-963
1-167
0-420
1-259
18-146
1-821
(100-00)
9-869
(100-00)
(11-71)
1-032
(10-46)
(4-22)
0-182
(1-84)
(12-64)
1-126
(11-41)
2. Water from the Black Sea. Gobel j
17*666
1*790
3. Water from the Sea of Assou. Gobel ... j
6-569
(100-00)
0-674
(10-26)
0-128
(l'9fi)
0-672
(10-23)
11*880
1*808
Mean j
8-800
0-958
0-243
1-019
15-897
1*806
(100-00)
(10-89)
(2-76)
(11-58)
Maximum ^
9-963
1-167
0-420
1-259
18*146
1*821
i(100-00)
(11-71)
(4-22)
(12-64)
Minimum |
6-569
0-674
0-128
0-672
11*880
1*790
(100-00)
(10-26)
(1-84)
(10-23)
B. — From the Caspian Sea.
1 /
2-731
(100-00)
1-106
(40-50)
0-268
0-700
(25-63)
6*236
2-283
(9-81)
2. Baer. From Tuik Karaga. Analysis by J
5-741
2-316
0-373
1-240
14-000
2-439
Mehner, Baer (Caspische Studien) [
,(100-00)
(40-34)
(6-50)
(21-60)
3. Baer. Bay of Kaidak or Karassi. Ana- J
23-976
10-112
1-432
4-657
56-814
2-370
lysis by Mehner, Baer (Caspische Studien) [
(100-00)
(42-11)
(5-91)
(19-42)
4. Baer. Bay of Mertuyi Kultak. Analysis j
12-504
5-613
1-733
2*096
31-000
2-480
by Mehner, Baer (Caspische Studien) )
(100-00)
(44-89)
(13-86)
(16-76)
5. Baer. Bay of Krasnowood. Analysis by f
6-182
3-494
0-760
1-471
16-410
2-654
Mehner, Baer (Caspische Studien) (_
(100-00)
(56-52)
(12-29)
(23-80)
Mean |
10-227
4-528
0-913
2-033
24-892
2*434
(44-27)
(8-93)
(19*88)
Maximum |
23-976
10-112
1-733
4-657
56-814
2-654
(56-52)
(13-86)
(25-63)
6-236
Minimum j
2-731
1-106
0-268
0-700
2-283
(40-34)
(5-91)
(16-76)
2 M
o
254
PROFESSOR FORCHHAMMER ON THE COMPOSITION
Eleventh Region. — The Atlantic, between the Equator and 30° S. latitude.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
\ 20*003
2-312
(11*56)
0-596
(2-98)
2*235
(11-17)
36*084
1-804
[ 20*491
2*465
(12-03;
0*598
(2*92)
2*218
(10*82)
37*155
1*813
j- 20*397
37*001
1-814
f 20-115
2-428
(12*07)
0-580
(2-88)
2*233
(11*10)
36-442
1-812
| 19*831
2-393
(12-07)
0-596
(3-01)
2-254
(11*37)
35-930
1-812
| 20-049
2-379
(11-87)
0-563
(2*81)
2*253
(11*24)
36*261
1-809
| 20*166
2-537
(12-58)
0*585
(2-90)
2-022
(10-03)
36-997
1*835
| 20-150
2-419
(12-03)
0*586
(2*91)
2-203
(10*96)
36*553
1-814
| 20-491
2*537
(12*58)
0-598
(3*01)
2*254
(11*37)
37*155
1*835
| 19*831
2-312
(11-56)
0*563
(2*81)
2-022
(10-03)
35*930
1-804
1. Valkyrie, February 11, 1848.
S. lat. 3° 19', W. long. 25° 34'
2. Valkyrie, February 1 6, 1848.
S. lat. 17° 9', W. long. 33° 29*
3. Sir James Ross.
S. lat. 22° 37', W. long. 34° 57'
4. Dr. Fischer, 1846.
S. lat. 23°' 5', W. long. 37° 15'
5. Dr. Fischer, 1846.
S. lat. 28° 15', W. long. 38° 26'
6. Captain Prevost, February 4, 1857-
S. lat. 29° 14', W. long. 47° 37'
7. Valkyrie, March 15, 1848.
S. lat. 29° 131', w. long. 38° 26'
Mean
Maximum
Minimum
Twelfth Region. — The Atlantic between S. lat. 30° and the southernmost points of
America and Africa.
Chlorine
Sulphuric
Lime
MsguGsi&a
All salts.
Coefficient.
acid.
Dr. Fischer, 1846. 1
19*809
2-329
0*583
2*234
35-807
1*808
S. lat. 30° 45', W. long. 42° 30' J
(11*76)
2*253
(2*94)
0-582
(11*28)
2*156
Dr. Fischer, 1846. 1
19*237
34-774
1*808
S. lat. 40° 3(y, W. long. 40° 50' (
(11*71)
2*194
(3-03)
0-557
(11*21)
2*135
Dr. Fischer, 1846. I
19*154
34*526
1-803 i
S. lat. 45° 20', W. long. 48° 40' f
(11-45)
2*245
(2-91)
0-518
(11-15)
2*190
Dr. Fischer, 1846. 1
18*909
34*151
1*806
S. lat. 50° 31', W. long. 52° 15' /
(11*87)
2*451
(2*74)
0*541
(11*58)
2*091
Fregat Valkyrie, 1848. \
S. lat. 36° lli', W. long. 6° 39' /
19*431
35-065
1*805
(12*61)
(2* 78)
(10-76)
Fregat Valkyrie, 1848.
19*713
2-404
0-553
2-156
35-907
1-821
S. lat. 37° 1 1 A', E- long. 12° 25^-' j
(12*19)
(2-81)
(11-04)
Mean j
19*376
2*313
0*556
2-160
35*038
1*809
(11*94)
(2-87)
(11-15)
Maximum |
19*809
2*451
(12-61)
0*583
(3-03)
2*234
(11*58)
35*907
1*821
Minimum j
18-909
2-194
(11*45)
0*518
(2*74)
2-091
(10*76)
34*151
1*803
Captain Prevost*. J
S. lat. 35° 46', W. long. 52° 57' i
' 17*721
1*615
(9*10)
Sulphuretted
0-448
(2*49)
1-899
(iO-72)
34*489
1*946
hydrogen.
* This sample has been left out in the calculation of the mean numbers because the quantity of sulphuric
acid was greatly diminished by putrefaction.
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
255
Thirteenth Region. — The sea between Africa and the East Indian Islands.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Galathea, September 24, 1845.
19753
2*361
0*600
2*207
35*802
1*812
S. lat. 31° 54', E. long. 72° 27'
(11*98)
(3*04)
(11*17)
2. Galathea, October 1, 1845.
19-498
2*341
0*569
2*105
35*381
1*814
S. lat. 14° 14', E. long. 83° 38'
(12*01)
(2*92)
(10*80)
3. Galathea, October 6, 1845.
19*381
2*334
0*591
2*005
35*169
1*815
N. lat. 0° 19', E. long. 84° 51'
,
(12*04)
(3*05)
(10*35)
4. Galathea, October 28, 1845.
14*289
1*724
0*446
1*699
25*879
1-818
N. lat. 17° 20', E. long. 88° 12'
.
(12*06)
(3*12)
(11-89)
32*365
5. Galathea, December 31, 1845.
17-838
2*131
0*543
1*944
1*814
N. lat. 18° 17', E. long. 90° 13' J
(11-94)
(3*04)
(10*90)
6. Galathea. ]
18*246
2*156
0*547
1-997
33*036
1-817 |
Nancovri on the Nicobar Islands J
>
(11*81)
(3*00)
(10*94)
7. Galathea, May 13, 1846. ]
17*970
2*132
0*547
1-979
32*766
1*823
S. lat. 4° 54', E. long. 107° 15', Sea of Java... J
►
(11*88)
(3*07)
(11*01)
8. Valkyrie, April 14, 1848. 1
S. lat. 38° 52', E. long. 30° 31' J
19*413
2*470
0*543
2*134
35*583
1-833
>
(12*72)
(2*80)
(10*99)
9. Valkyrie, April 19, 1848. 1
S. lat. 36° 59', E. long. 47° 23' J
19-710
2*349
0*572
2*193
35*701
1*816
f
(11*92)
(2*90)
(11*13)
10. Valkyrie, April 26, 1848. ]
19*548
2*380
0*588
2*101
35*415
1*817
S. lat. 35° 2\ E. long. 62° 52' J
(12*17)
(3*01)
(10-75J
11. Valkyrie, May 14, 1848.
S. lat. 1° 56', E. long. 81° 5' J
19*626
2*330
0*567
2*207
35*512
1*809
(11-87)
(2*89)
(11*24)
12. Valkyrie, May 21, 1848. 1
N. lat. 12° 3', E. long. 80° 8' J
L
18*763
2*250
0*567
2*086
33*809
1*802
r
(11-99)
(3*02)
(11*12)
Mean ■
r
18*670
2*247
0*557
2*055
33*868
1*814
l
(12*04)
(2*98)
(11*01)
Maximum <
r
19*753
2*470
(12*72)
0*600
2*207
35*802
1*833
i
(3*12)
(11-89)
Minimum -
f
14*289
1*724
(11*81)
0*446
(2*80)
1*699
(10*35)
25*879
1*802
Fourteenth Region. — The sea between the S.E. shore of Asia, the East Indian and the
Aleutic Islands.
1
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Galathea, May 18, 1846. 1
The Chinese Sea. >
S. lat. 0° 33', E. long. 107° 22' J
17*757
2*104
(11*85)
0*516
(2*90)
1*958
(11*03)
32*370
1*823
2. Galathea. 1
18*486
2*258
0*572
2*067
33*680
1-822
N. lat. 4° 30', E. long. 107° 16' /
(12-21)
(3-03)
(11*19)
3. Galathea. )
17-923
2-160
0*533
1*961
32*533
1-815
N. lat. 25° 40', E. long. 120° 50' j
(12*05)
(2*97)
(10*94)
4. Galathea. 1
18*564
2*209
0*552
2*022
33*580
1*809
N. lat. 30° 56', E. long. 127° 30' J
(II 90)
(2*97)
(10*89)
5. Galathea.
18*847
2*257
0*575
2*089
34*153
1*812
N. lat. 30° 56', E. long. 139° 39' /
(11-98)
(3*05)
(10*08)
6. Galathea.
18*873
2*247
0-613
2*046
34*234
1*814
N. lat. 38° 31', E. long. 148° 27' /
(11-90)
(3-25)
(10*84)
7- Galathea. 1
18*788
2-213
0*580
2*048
33-990
1*809
N. lat. 38° 35', E. long. 148° 44' J
(11-78)
(3*09)
(10*90)
Mean |
18*462
2*207
0*563
2*027
33-506
1*815
(11*95)
(3*05)
(10*93)
34-234
1*823
Maximum j
18*873
2*258
0*613
2*089
(12*05)
(3*25)
(11*19)
32-370
1*809
Minimum j
17-757
2*104
0*516
1*958
(11-78)
(2*90)
(10*84)
1
256
PEOFESSOE FOECHHAMMEE ON THE COMPOSITION
Fifteenth Region. — The sea between the Aleutic Islands and the Society Islands.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Galathea, September 11, 1846.
N. lat. 38° 26', E. long. 172° 11’
2. Galathea, September 17, 1846.
N. lat. 38° 42', W. long. 176° 53'
3. Galathea, September 21, 1846.
N. lat. 37° 3', W. long. 160° 5' 1
4. Galathea, September 24, 1846. |
N. lat. 32° 8', W. long. 150° 17' 1
5. Galathea, October 5, 1846.
Off Honolulu, Sandwich Islands J
6. Galashea.
Off Matuiti J
7. Galathea.
Off Borabora J
f
18- 908
19- 006
19*244
19-824
19-625
19*943
19*917
2-195
(11-61)
2-220
(11-68)
2-243
(11-65)
2-316
(11-68)
2-283
(11-63)
2-326
(11-66)
2-347
(11-78)
0-545
(2-88)
0-535
(2-82)
0-555
(2-88)
0-549
(2-83)
0-580
(2-95)
0-610
(3-06)
0-623
(3-13)
2-066
(10-93)
2-078
(10-93)
2-110
(10-69)
2-209
(11-14)
2-152
(10-96)
2-224 •
(11-15)
2-252
(11-31)
34-157
34-274
34- 715
35- 877
35- 395
36- 051
36-061
1-806
1-803
1-804
1-809
1-804
1-808
1-805
Mean ■
Maximum •
Minimum •
I
19*495
19-943
18-908
2-276
(11*67)
0-347
(11-78)
2-195
(11-61)
0-571
(2-93)
0-623
(3-13)
0-535
(2-82)
2-156
(11-06)
2-252
(11-31)
2-066
(10-69)
35- 219
36- 061
34-157
1-807
1-809
1-803
Sixteenth Region. — The Patagonian current of cold Water.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Dr. Fischer. 1
18-769
2-133
0*507
2-116
33-788
1-800
S. lat. 57° 27', W. long. 66° 57' J
(11*37)
(2-70)
(11-27)
2. Dr. Fischer.
18-796
2-210
0*546
2-048
33-969
1-807
S. lat. 52° 38', W. long. 76° 20' J
(11-76)
2-238
(2*91)
0-560
(10-90)
2-036
3. Dr. Fischer.
18-760
33-980
1-811
S. lat. 47° 40', W. long. 78° 25' J
(11*89)
2-226
(2-98)
0-563
(10-85)
2-100
4. Dr. Fischer. |
18-768
23-932
1-808
S. lat. 38° 10', W. long. 78° 14' j
(11-86)
2-224
(3-00)
0-537
(11*19)
2-079
5. Dr. Fischer. j
18-754
33-976
1-812
S. lat. 33° 54', W. long. 74° 23’ 1
(11-86)
2-257
(2-86)
0-531
(11*09)
2-076
6. Captain Prevost. |
18-976
34-152
1-800
S. lat. 35° 22', W. long. 73° 49' J
(11*89)
(2-80)
(10-94)
Mean -
18-804
2*215
0-541
2-076
33-966
1-806
(11*78)
(2-88)
(11-04)
Maximum <
18-976
2-257
(11*93)
0-563
(3-00)
2-116
(11-27)
34-152
1-812
Minimum j
18-754
2-133
(11*37)
0-507
(2*70)
2-036
(10-85)
33-788
1-800
Seventeenth Region. — The South Polar Region.
Chlorine.
1 Sulphuric
1 acid.
Lime.
Magnesia.
All salts.
Coefficient.
1. Sir James Eoss, January 30, 1841. 1
S. lat. 77° 32', E. long. 188° 21'. Near the V
ice barrier J
2. Sir James Eoss, February 25, 1841. |
S. lat. 74° 15', E. long. 167° O'. Near Caulmans >
i Island ; J
3. Sir James Ross, March 6, 1841. 1
| S. lat. 65° 57', E. long. 164° 34' /
15-748
8-477
20-601
1-834
(11-65)
1- 053
(12-42)
2- 586
(12-55)
0-498
(3-16)
0-251
(2-96)
0-623
(3-02)
1- 731
(10-99)
•887
(10-46)
2- 231
(10-83)
28-565
15-776
37-513
1-814
1-861
1-821
Mean* j
14-942
1-824
(12-21)
4-57
(3-06)
1-616
(10-81)
27-285
1-826
* These mean numbers are uncertain, the number of observations being very limited, and so very different. I
should think that the first observation will he a fair sample of South Polar water, and have preferred it to the
mean of the three observations in the calculation of the means of the whole ocean.
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
257
Comparison of the Means of all the Regions of the Ocean (German Ocean, Kattegat,
Baltic, Mediterranean, and Black Sea excepted).
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
I. The Atlantic between the equator and
N. lat. 30° J
20-034
2-348
(11-75)
2-389
(12-05)
0-595
(2-98)
0-607
(3-07)
2-220
(11-11)
2-201
(11-10)
36-253
1-810
II. The Atlantic between N. lat. 30° and a line
front the north point of Scotland to New-
foundland
>
19-828
35-932
1-812
III. The northernmost part of the Atlantic... -
IV. The East Greenland Current
'
19*581
19-458
2-310
(11-80)
2-329
(11-97)
0-528
(2-97)
2-160
(11-03)
35-391
35-278
1-808
1-813
V. Davis Straits and Baffin’s Bay <
'
18-379
2-208
(12-01)
0-510
(2-77)
2*064
(11-23)
33-281
1-811
XI. The Atlantic between the equator and ]
20-150
2-419
0-586
2-203
36-553
1-814
S. lat. 30° J
f
(12-03)
(2-91)
(10-96)
XII. The Atlantic between S. lat. 30° and a~l
line from Cape Horn to the Cape of Good
Hope J
>
19-376
2-313
(11-94)
0-556
(2-87)
2-160
(11-15)
35-038
1-809
XIII. The Ocean between Africa, Borneo, ]
18-670
2-247
0-557
2-055
33-868
1-814
and Malacca J
(12-04)
(2-98)
(11*01)
XIV. The Ocean between the S.E. coast of 1
Asia, the East Indian, and the Aleutic
Islands J
18-462
2-207
(11-95)
0-563
(3-05)
2-027
(11*98)
33-506
1-815
XV. The Ocean between the Aleutic and the]
19*495
2-276
0-571
2-156
35-219
1-807
Society Islands J
>
(11-67)
(2-93)
(11-06)
XVI. The Patagonian cold-water current ... <
r
18-804
2-215
(11-78)
0-541
(2-88)
2-076
(11-04)
33-966
1-806
XVII. The South Polar Sea <
j
15-748
1-834
(11-65)
0-498
(3-16)
1-731
(10-99)
28-565
1-814 i
Mean
18-999
2-258
0-556
2-096
34-404
1-811
Mean proportion of the most"!
i
important substances in sea-
water, chlorine=l00 J
11-88
2-93
11-03
f
Enuivalents
429
45
16
82
Comparison between the quantity of Salt in the water of the surface and the depth
of the Sea, between Africa and the East Indies.
Depth.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
r
Surface
19*626
2-330
0-567
2-207
35-512
1-809
Valkyrie, May 14, 1848. J
1
(11*87)
(2-89)
(11-25)
S. lat. 1° 56', E. long. 81° 5' 1
215 feet
19-606
2-451
0-558
2-147
35-819
1-827
L
(12-50)
(2-85)
(10-75)
1
r
Surface
19*548
2-349
0-588
2-101
35-415
1-817
Valkyrie, April 28, 1848. J
I
(12-02)
(3-01)
(10-75)
S. lat. 35° 2', E. long. 62° 52' i
300 feet
19-786
2-380
0-572
2-218
35-671
1-803
L
(1 203)
(2-89)
(11-21)
258
PROFESSOR FORCHHAMMER ON THE COMPOSITION
Comparison between the quantity of Salt in the water of the surface and the depth
of the Sea, between the East Indian and Aleutic Islands.
Depth.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
I
r
Surface
18-873
2-178
0-615
2-046
34-052
1-804
Galathea, August 27, 1846.
N. lat. 38° 31', E. long. 148° 27' .
J
(11-54)
(3-26)
(10-84)
..1
300 feet
19-075
2-249
0-543
2-132
34-426
1-805
1
L
(11-79)
(2-85)
(11-18)
I
r
Surface
18-846
2-258
0-572
2-067
34-132
1-811
Galathea, May 23, 1846.
••
(11*98)
(3-04)
(10-97)
N. lat. 4° 30', E. long. 1073 16' .
i
360 feet
18-885
2-195
0-567
2-147
34-033
1-802
1
L
(11-62)
(3-00)
(11-38)
Comparison between the quantity of Salt in Sea-water from different depths in the South
Atlantic Ocean.
Samples taken by Sir James Boss.
Depth.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
900 feet
19-763
2-584
0*657
2-249
36-165
1-830
(13-07)
(3-32)
(11-38)
36-358
1800 feet
19*991
2-456
0-566
2-191
1-819
Sir James Ross, June 10, 1844. J
(12-29)
(2-83)
(10-96)
S. lat. 0° 15', W. long. 25° 54' |
4500 feet
19*786
2-398
0-554
2-320
35-889
1-814
(12-12)
(2-80)
(11*73)
36-313
5400 feet
20*007
2-418
0-574
2*187
1-815
(12-09)
(2*87)
(10-93)
Sir James Ross, June 2, 1 843. T
S. lat. 14° 22', W. long. 22° 35' /
3600 feet
19*743
Sir James Ross, June 4, 1843, 1
S. lat. 15° 23', W. long. 23° 40' /
Sir James Ross, June 8, 1843. f
S. lat. 21° 48', W. long. 31° 24' j
2700 feet
19*346
900 feet
19*604
Sir James Ross, June 9, 1843. I
! S. lat. 22° 24', W. long. 32° 53' J
f
3600 feet
19-627
Surface
20-397
Sir James Ross, June 10, 1843. J
S. lat. 22° 37', W. long. 34° 57' i
900 feet
1800 feet
2700 feet
20-323
23-189
20-331
l
3600 feet
20-405
Surface
20-166
2-537
0-585
2-022
36-997
1-835
Valkyrie, March 15, 1848. J
(12-58)
(2-90)
(10-03)
S. lat. 29° 15'-5, W. long. 38° 26' ..A
480 feet
19*736
2-448
0-573
2-023
36-227
1-835
(12-40)
(2-90)
(10-25)
Sir James Ross, March 28, 1843. f
'6300 feet
19*635
2-346
0-631
2-140
35-607
1-813
S. lat. 43° 10', Long. 14° 44' <p \
(11-95)
(3-21)
(10-90)
Sir James Ross, Dec. 21, 1840, f
S. lat. 57° 52', Long. 170° 30' f ... \
Surface
19-396
2-293
0-624
2-108
35-131
1-811
(11-82)
(3-22)
(10-87)
Sir James Ross, March 6, 1841, f
S. lat. 65° 57', Long. 1 64° 37' <p ... {
Surface
20-600
2-586
0-623
2-231
37*513
1-821
(12-55)
(3-02)
(10-83)
15-776 j
1-861
Sir James Ross, January 25, 1841. f
Surface
8-477
1-053
0-251
0-887
S. lat. 74° 15', Long. 167° 0' <p |
(1-242)
(2-96)
(10-46)
i
Or SEA-WATER IN THE DIFEERENT PARTS OF THE OCEAN.
259
Comparison between the quantity of Salt in Sea-water from the surface and different
depths in the North Atlantic Ocean.
Samples taken by Sir James Boss, Dr. Bin]
Mr. Gram, Captain Schulz, and Admiral vo
n Depth.
Chlorine.
Sulphuric
acid.
Lime.
Magnesia.
All salts.
Coefficient.
Dockum.
Surface
18*524
2*268
0*530
2*119
35*595
1*814
Dr. Rink, July 5, 1849. J
(12*24)
(2*86)
(11*39)
W. from Disco. N. lat. 69° 45f )
420 feet
18*532
0*542
2*098
1
(2*92)
(11*32)
Surface
19*306
2*310
0*575
2*119
35*067
1*816
Merchant-Capt. Gram, May 20,1845 J
W. long. 39° 4', N. lat. 59° 45' ... )
(11*97)
(2*98)
(10*98)
270 feet
19*364
2*337
0*579
2*186
34*963
1*806
\
(12*07)
(2*99)
(11*28)
Surface
19*671
2*342
0*592
2*210
35*576
1*809
Merchant-Capt. Gram, May 5, 1845. J
(11*91)
(3*01)
(11*23)
W. long. 7° 52', N. lat.59° 50' A
270 feet
19*638
2*338
0*598
2*210
35*462
1*806
(11*91)
(3*05)
(11*25)
Between Iceland and Greenland. Meai
Surface
35*356
Ditto, Mean of eight samples from j
1200 to
1800 feet
}
35*057
r
Surface
19*644
2*556
0*589
2*273
i
(13*01)
(3*00)
(11*57)
35*925
1*829
Captain Schulz, R.D.N., 1845. J
W. long. 9° 30', N. lat. 47° 45' 4
390 feet
19*640
2*595
0*623
2*357
(13*21)
(3*17)
(12*00)
35*925
1*829
1
510 feet
19*699
2*594
0*628
2*296
l
(13*17)
(3*19)
(11*66)
36*033
1*829
r
Surface
20*098
2*425
0*606
2*391
Admiral von Dockum, Aug. 13, 1845. J
210 to
(12*07)
(3*02)
(11*90)
36*360
1*809
W. long. 54° 15', N. lat. 40° 21' ... )
270 feet
20*172
2*425
0*605
2*261
1
(12*02)
(3*00)
(11*21)
36*598
1*814
f
Surface
20*302
2*450
0*620
2*301
36*705
1*808
Captain Irminger, March 17, 1849.J
(12*07)
(3*05)
(11*33)
W. long. 64°, N. lat. 25° 40' )
2880 feet
20*222
2*380
0*581
2*274
36*485
1*804
(11*77)
(2*87)
(11*26)
Sir James Ross July 29, 1843. }
' 2700 feet
20*238
W. long. 32° 10', N. lat. 20° 54' ... \
3600 feet
19*703
Sir James Ross, July 27, 1843. f
Surface
20*429
W. long. 29° 56', N. lat. 18° 1 6' ... |
3600 feet
19*666
Sir James Ross, July 26, 1843. f
W. long. 29° O', N. lat. 16° 57' A
Surface
900 feet
2700 feet
20*186
20*029
19*602
Sir James Ross, July 25, 1843. f
W. long. 28° 10', N. lat. 15° 38' ... \
Surface
20*081
6360 feet
19*747
Sir James Ross, July 24, 1843. {
" 900 feet
19*934
W. long. 27° 15', N. lat. 14° 18' ...^
2700 feet
3600 feet
19*580
19*705
f
Surface
20*114
2*343
0*619
2*315
36*195
1*800
Sir James Ross, July 22, 1843. 1
(11*65)
(3*08)
(11*51)
W. long. 25° 35', N. lat. 12° 36' ...4
1850 feet
19*517
2*271
0*598
2*128
35*170
1*802
[
(11*64)
(3*06)
(10*90)
Sir James Ross, July 11, 1843. f
Surface
20*035
W. long. 25° 6', N. lat. 11° 43' "<
3600 feet
19*855
4500 feet
19*723
Sir James Ross, July 6, 1843. f
Surface
20*070
W. long. 27° 4', N. lat. 6° 55' 4
900 feet
3600 feet
19*956
19*885
r
1
Surface
19*757
2*303
0*584
2*333
35*737
1*809
(11*66)
(2*96)
(11*81)
Sir James Ross, 1843.
1800 feet
19*715
2*265
0*547
2*253
35*520 |
1*802
W. long. 25° 54', N. lat. 1° 10' 4
3600 feet
(11*49)
(2*77)
(11*43)
19*548
2*322
0*545
2*239
35*365
1*809
Li
(11*88)
(2*79r
(11*45)
N
MJDCCCLXV.
2
260
PROFESS OB EORCHHAMMER ON THE COMPOSITION
Comparison of water from the surface and the depth of the North Atlantic
1
Depth.
Chlorine.
Sulphuric
acid.
Lime.
Potash.
Porcupine. 1
N. lat. 51° If, W. long. 14° 21' ... 1
2370 feet
19-677
2-343
0-556
0-442
Sp. gr. 1-0270.
(11-91)
(2-83)
(2-24)
Porcupine, June 25, 1862.
N. lat. 50° 56', W. long. 12° 6' ... i-
6000 feet
19-776
2-376
0-610
0-381
Sp. gr. 1-0282. J
(12-01)
(3-08)
(1-93)
Porcupine, June 27> 1862.
N. lat. 51° 9', W. long. 15° 59' ... >-
Surface
19-690
2-285
0-577
0-433
Sp. gr. 1-0280. J
Porcupine, July 3, 1862. 1
N. lat. 52° 9', W. long. 15° 10' ... V
(11-60)
(2-93)
(2-20)
Surface
19-706
2-381
0-570
0-367
Sp. gr. 1-0265. I
Porcupine, July 3, 1862. 1
N. lat. 52° 9', W. long. 15° 10' ... 1
(12-08)
(2-89)
(1-86)
5100 feet
19-752
2-297
0-580
0-433
Sp. gr. 1-0280. 1
(11-73)
(2-94)
(2-19)
Porcupine, Aug. 29, 1862. |
N. lat. 51° 58', W. long. 12° 47' ... 1
2400 feet
19*666
2-323
0-611
0-364
Sp. gr. 1-0280. J
(11-811
(3-11)
(1-85)
j
Surface
19-645
2*339
0-583
0-335
Porcupine, August 28, 1862. (
(11*91)
(29-7)
(1-71)
N. lat. 52° 40', W. long. 15° 58' ... f
10,500 feet
19-758
2-423
0-563
0-325
(12-26)
(2-90)
(1-64)
Porcupine.
N. lat. 53° If, W. long. 12° 55' ... 1
Sp. gr. 1-0280.
Surface
19-651
2-352
0-557
0-374
1200 feet
19*424
(11-97)
2-405
(12-38)
(2-83)
0-559
(2-83)
(1-90)
0-351
(1-81)
Porcupine, August 16, 1862.
N. lat. 55° 32', W. long. 12° 11' ... 1
Sp. gr. 1-0255.
Surface
9780 feet
19-616
19-686
2-359
(11-99)
2-330
0-545
(2-78)
0-599
0-325
(1-65)
0-323
(11-84)
(3-04)
(1-64)
Mean of surface observations
19-662
2-342
0-566
0-367
(11-9.1)
(2-88)
(1-87)
Mean of observations from the depth ...
19*677
2-357
0-583
0-374
(11-98)
(2-96)
(1-90)
Water from the Red Sea, and from different depths in the Baltic.
Depth.
Chlorine.
Sulphuric
acid.
Lime.
Potash.
Water from the Red Sea.
|
Procured by Mr. Polack of Alexandria
23-730
2-889
0-689
0-387
f
(12-17)
(2-90)
(1-63)
From WTady Rarandel, upon the Sanai
23-171
2-761
peninsula, taken by Mr. Neergaard ...
(11-92)
r
Surface
3-256
0-407
0-132
0-056
(12-50)
(4-05)
(1*71)
108 feet
3-663
Baltic.
240 feet
3-881
Water from Svartklubleen, taken by
300 feet
3-912
Messrs. Widegreen and Nystrom |
510 feet
3-969
600 feet
3-958
0-565
0-137
0-058
(14-27)
(3-46)
(1-47)
720 feet
3-960
1
1
948 feet
3-977
OF SEA-WATER IN THE DIFFERENT PARTS OF THE OCEAN.
261
Sea between lat. N. 51° l'£ and 55° 32'; and long. W. 12° 6' and 15° 59'.
Magnesia.
Silica, &c.
Chloride of
Sulphate of
Sulphate of
Chloride of
Chloride of
All salts.
Coefficient.
sodium.
magnesia.
lime.
potassium.
magnesium.
2-211
(11-24)
0-110
27-977
2-376
1-353
0-700
3-212
35-728
1-816
2-211
(11-18)
0-100
28-056
2-279
1-483
0-603
3-344
35-865
1-814
2-235
(11-35)
0-074
27-735
2-213
1-402
0-686
3-438
35-548
1-805
2-226
(11-30)
0-105
28-005
2-373
1-385
0-581
3-305
35-754
1-814
2-179
(11-03)
0-071
28-119
2-298
1-409
0-685
3-206
35-788
1-812
2-175
(11-06)
0-071
27-914
2-193
1-487
0-575
3-330
35-570
1-809
2-128
(10-83)
0-071
28-139
2-279
1-418
0-531
3-145
35-583
1-811
2-209
(11-18)
0-078
28-188
2-451
1-369
0-517
3-203
35-806
1-812
2-145
(10-92)
0-113
28-119
2-355
1-354
0-592
3-131
35-664
1-815
2-183
(11-24)
0-104
27-740
2-432
1-359
0-555
3-158
35348
1-820
2-225
(11-34)
0-088
27-916
2-379
1-326
0-517
3-298
35-524
1-811
2-182
(11-08)
0-069
28-081
2-253
1-457
0-511
3-261
35-632
1-810
2-192
(11-15)
0-090
27-983
2-320
1-377
0-581
3-263
35-615
1-811
2-193
(11-14)
0-086
28-011
2-326
1-417
0-592
3-245
35-677
1-813
Water from the Red Sea, and from different depths in the Baltic.
Magnesia.
Silica, &c.
Chloride of
sodium.
Sulphate of
magnesia.
Sulphate of
lime.
Chloride of
potassium.
Chloride of
magnesium.
All salts.
Coefficient.
2-685
(11-31)
0-136
33-871
2-882
1-676
0-612
3-971
43-148
1-818
0-403
(12-38)
0-027
4-474
0-329
0-322
0-089
0-678
5-919
1-818
0-441
(11-14)
0-072
5-810
0-632
0-333
0-092
0-526
7-465
1-886
Water from the Mediterranean. — Comparison between water from the surface and from different depths.
262
ON THE COMPOSITION OE SEA-WATER.
Silica, }&c. 1 All salts. Coefficient.
I' 1 1
1-803
1-805
1-829
1-805
1-836
1-820
1-805
g
00
1-814
1-810
s
1-808
1-813
1-811
2 g
t &
11 fill 11
i
37- 177
38- 541
CO
?
n
I
S : S
: ?
£ i S
CO
1 I
0-093
0-083
0-138
0-087
0-075
i
0 GO
1 1
1
!
»
afsf
1 ill llsllfi gf
: or ^2 : or ^or ^or ^ • dr^.
if
sfsf
GTO&C
if
dr^
jf
III ll
Potash.
ZtZt
I hi linn i it
Zt
tr 5 <?»
6 oC
1?
oC
1?
®C
Lime.
<£> eo"
Sill
hi man ii
O
IE
III!
fl
It
III II
fl
or ^dr ^ dr 2U®* O®* 0®* 0®* O®* O®* CJ®* O®* O®1 O®1 CJ®* C- ®* C-®* O®1 O®* CJ®* C-
s.? « ? s ?
Chlorine.
isg'ggs.sss.ssggssss'gss;
siSSSSS. S5SS§SSS««®
20- 845
21- 155
18-999
Depth.
Surface.
Surface.
540 feet
Surface.
Depth *
Surface.
Depth*
Surface.
Depth *
Surface.
420 feet
Surface.
300 feet
Surface.
Surface.
390 feet
Surface *.
522 feet
Surface.
522 feet
1. Straits of Gibraltar, procured by Mr. Ennis, Falmouth, f
1837 }
2. Straits of Gibraltar, taken by Captain Schulz, September 1
28, I860 1
3. Straits of Gibraltar, taken by Captain Schulz, September J
28, I860, from 540 feet depth 1
4, 5*. A little on the Mediterranean side of the Straits, N. lat. 7
36° 9', W. long. 4° 2', September, 29, I860; j
6, 7** Between the Balear island and the Spanish coast, N. lat.J
i 40° 28', E. long. 1° 48', October 8, I860 1
>
8, 9*. Between the Balear island and the Spanish coast, N. lat.J
41° 12', E. long. 2° 23', October 10, I860 1
10, 11. About midway between Corsica and Barcelona, N. lat.J
49.° 95'. F. Innor. fi° ft'. fWnher 19 1 Sfift 1
12, 13. Between Sardinia and Naples, N. lat. 40° 25', E. long.)
11° 43'. fWnher 9ft. 1 8fift 1
14. Malta, procured by Mr. Ennis, 1837 /
15, 16. Somewhat to the east of Malta, N.lat.36° 10', E.long.J
1<1° lft' IS. ISfift 1
tij
J
w
§‘
fe
&
A
I
» o
i 11
! 15
1 i|
: |e
5 « ®
; ti
1 19, 20. Between Candia and the coast of Africa, N. lat. 33° 34', J
I'. Inna. 94° 34'. OctnUor 98 1 8fift 1
r
[
j
?
)
i
Mean of surface observations j
Mean of observations of deep water j
Mean of the surface of the ocean -j
The depth in samples 5, 7, 9 is not exactly noticed, hut it must have heen between 300 and 540 feet.
[ 263 }
V. On the Magnetic Character of the Armour-plated Ships of the Royal Navy , and on
the Effect on the Compass of particular arrangements of Iron in a Ship. By
Frederick John Evans, Esq., Staff Commander R.N., F.R.S. , Superintendent of the
Compass Department of Her Majesty's Navy; and Archibald Smith, Esq., M.A.,
F.R.S., late Fellow of Trinity College , Cambridge, Corresponding Member of the
Scientific Committee of the Imperial Russian Navy.
Received March 9, — Read March 16, 1865.
The present paper may be considered as a sequel to a paper published in the Philo-
sophical Transactions for 1860, page 337, under the title “ Reduction and Discussion of
the Deviations of the Compass observed on board of all the Iron-built Ships, and a selec-
tion of the Wood-built Steam-ships in Her Majesty’s Navy, and the Iron Steam-ship
‘ Great Eastern’; being a Report to the Hydrographer of the Admiralty. By F. J. Evans,
Master R.N.” Like the former, the present paper is presented to the Royal Society,
with the sanction of the Lords Commissioners of the Admiralty.
In the brief interval which has elapsed since the publication of that paper, changes
of the greatest importance have taken place in the construction of vessels of war, which
have been accompanied by corresponding changes in the magnetic disturbance of their
compasses. Not only has there been a great increase in the surface and mass of iron
used in the construction of those parts of the ship in which iron was formerly used,
but iron has been adopted for many purposes for which it was not then used, and much
of the iron thus added far exceeds in thickness any that was formerly in use. Among
the masses thus added we may specially mention iron masts and yards, armour-plating,
and gun-turrets.
These changes have materially affected the problem of the correction of the deviation
of the compass. They have not only greatly increased those errors which were formerly
taken into account, but they have given importance to errors and causes of error which
it was formerly considered might be safely neglected. These changes led to, if they did
not necessitate, a complete revision of the mathematical theory of the deviations of the
compass, and of the practical methods of ascertaining and applying the deviation.
This revision was undertaken by us at the request of the Admiralty, and the results
are contained in the ‘ Admiralty Manual for ascertaining and applying the Deviations
of the Compass caused by the Iron in a Ship,’ published by the order of the Lords
Commissioners of the Admiralty. London: Potter, 1862. Second edition, 1863. It
is gratifying to us to be able to state, as an indication that this work has been found
mdccclxv. 2 o
264 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
useful by others engaged in the like investigations, that it has been already translated
into Russian, French, and German.
The methods of reduction previously in use, and which are those made use of in the
paper already referred to, as well as in the valuable Reports of the Liverpool Compass
Committee, are those deduced from the approximate formula for the deviation,
S=A+B sin £'+C cos £'+D sin 2£'+E cos 2£',
as given in the Supplement to the ‘ Practical Rules for ascertaining the Deviations of
the Compass which are caused by the Ship’s Iron,’ published by the Admiralty in 1855.
In connexion with this formula use was made of the invaluable graphic method known
as Napier’s curve.
At that time observations of horizontal and vertical force did not enter into the usual
routine of observations made on board ship, although many very valuable observations
of these forces had been made by the Liverpool Compass Committee ; and no formulae
had been published for the deduction from such observations of any of the parts of
the deviation. This will explain why, in the paper of 1860, the discussion was con-
fined to the coefficients which are derived from observations of deviation only, viz.
A, B, C, D, E.
The new modes of construction brought into prominence the diminution of mean
directive force which a compass-needle suffers in an iron ship, particularly when placed
between two iron decks. It is well known that in the interior of a thick iron shell the
effect of the earth’s magnetic force is nearly insensible. This is not caused by the iron
of the shell intercepting the earth’s magnetism, but by an opposite magnetism being
induced which nearly neutralizes the earth’s magnetism whatever be the inductive capa-
city of the shell, and whatever be the thickness of the shell, provided only that the
thickness bears a considerable proportion to the diameter of the shell. When the shell
is thin, the diminution of force is still considerable, but it then depends in a very much
greater degree on the inductive capacity and the thickness of the shell. The destruction
of force is total in the case of a spherical shell whatever be its thickness, if the inductive
capacity be infinite.
An iron ship, as regards a compass-needle between decks, may be compared to a thin
iron shell. Before the ship is launched, and when every particle of iron in her structure
has by continued hammering become saturated with magnetism, she may be compared
to a thin shell of high inductive capacity, and the directive force on a needle in the inte-
rior is consequently greatly diminished. When the ship is launched and placed succes-
sively on every azimuth, she may be compared to a thin shell of low inductive capacity.
The mean directive force on a needle in her interior will be considerably diminished,
but the diminution will depend much more on the thickness of the surrounding iron.
This diminution has been found so considerable in the case of iron-built and particu-
larly iron-plated ships, as to have become a matter of serious consideration in selecting
a place for the compasses.
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 265
Observations of horizontal force, for the purpose of ascertaining the diminution of the
mean directive force, have now become part of the regular series of observations made
in ships in which its determination is of importance, and formulae and graphic methods,
for the purpose of deducing from them the proportion of the mean value of the directive
force to North to the earth’s horizontal force, are given in the ‘ Admiralty Manual.’
Another error of the greatest importance, which has been brought into prominence
in the modern class of iron -built ships, is the “ heeling error.”
The deviations obtained by the usual process of swinging are for a vessel in an upright
position. It is found by experience that, as the vessel heels over, the north end of the
compass-needle is drawn either to the weather or lee side, generally in the northern
hemisphere to the former, and the deviation so produced when the ship’s head is near
North or South, often exceeds the angle of heel. This not only produces a deviation
which may cause a serious error in the ship’s course, but if the ship is rolling, and
particularly if the period of each roll approximates to the period of oscillation of the
compass, it produces a swinging of the compass-needle which may make the compass
for the time useless for steering.
This error had been known to exist, and its amount had even been measured in the
case of Her Majesty’s ships Eecruit (1846), Bloodhound (1847), Sharpshooter (1848),
and in various cases recorded by the Liverpool Compass Committee (1855-61); but no
method had been proposed for determining this error by observations made with the
ship upright, and considerable obscurity was even supposed to rest on the causes and
law of this deviation. The application of Poisson’s formulae has entirely removed the
obscurity, and furnishes an easy method of determining the heeling error by observations
of vertical force made on one or more directions of the ship’s head. These observations
have likewise now become a regular part of the complete series of magnetic observations
made in the principal iron ships of Her Majesty’s Navy.
Fortunately the mechanical correction of this error, when its amount is ascertained, is
not difficult, and as the correction does not affect the deviation when the ship is upright,
its application is free from some of the objections which exist to the mechanical correc-
tion of the ordinary deviation.
The importance of being thus able to detect the heeling error by observations of a
simple kind made with the ship upright is great, and this is perhaps one of the most
practically useful of the immediate results of the application of mathematical formulae
to this subject.
Besides these, which may be called the direct results of the additional observations
now made, and of the application to them of the mathematical formulae, there are some
other results of the use of the formulae which have a practical value as well as a theo-
retical interest.
Among these is the separation into their constituent parts of the several coefficients,
so as to indicate the particular arrangements of the iron from which each arises. This
is not only of great theoretical interest, but is of considerable practical importance in
2 o 2
266 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
indicating the place which should be selected for the compass, and also in enabling
us to anticipate or account for the subsequent changes which take place in the
deviation.
Another and perhaps even more important result is that we are enabled by observa-
tions made with the ship’s head in one direction, and therefore when she is in dock or
even on the stocks, to determine the coefficients and construct a table of deviations,
including the heeling error, without swinging the ship. To explain this, we may observe
that for the complete determination of the deviations of the compass when the ship is
upright and in one geographical position, six coefficients are required. But of these
two vanish when the iron is symmetrically arranged, two more are so nearly the same
in ships of the same class that they can be estimated with a near approximation to the
truth ; we have therefore only two coefficients left, and these can be determined by an
observation of deviation, and an observation of horizontal force made without altering
the direction of the ship’s head.
So as regards the heeling error, to determine this three additional quantities are
generally necessary, but of these one is zero when the iron is symmetrically arranged ;
another may be estimated, and the third may then be determined by a single observation
of vertical force.
The quantities so estimated change little after the ship is completed, so that any
assumption made as to their value may he checked by subsequent observations.
These considerations will show the importance of not only making the observations
we have mentioned, but of reducing the observations made, and of tabulating, discussing,
and publishing the results of the observations. In the Tables it will be seen that the
original observations are not given ; they, as well as the curves and computations by
which the coefficients are derived, are carefully preserved among the records of the
Admiralty Hydrographic Office, and may at any time be referred to ; but the coefficients,
at least so far as regards the deviation of the horizontal needle, represent so exactly
the observations made, that to give them here at length would he an unnecessary waste
of space.
The observations, the results of which are tabulated, were made in the following
manner. The deviations of the Standard Compass were observed by reciprocal simul-
taneous bearings of the Standard Compass and an azimuth compass on shore, in the
manner described in the ‘Admiralty Manual.’ The admirable construction of the Admi-
ralty Standard Compass, as regards design and workmanship, accuracy of adjustment
and magnetic power, leaves nothing further to be desired for such observations. The
arrangement of its four needles obviates, as we have shown in a former paper*, the
sextantal error caused by the length of the needle when acted on by iron placed near it.
The deviations of the steering and maindeck compasses were obtained by observations
of the direction of the ship’s head by those compasses, made simultaneously with the
observations of the Standard Compass. These compasses in the Royal Navy are of
* Philosophical Transactions, Part II. 1862.
CHARACTER OE THE ARMOUR-PLATED SHIPS OE THE ROYAL NAVY. 267
simpler construction than the Standard, not being fitted with the azimuth circle, and
generally having only two needles, but they are of little inferior accuracy, magnetic
power and delicacy. The two needles are arranged so as to obviate the sextantal error
above alluded to.
The Tables of deviations of these compasses have in all cases been most satisfactory,
and on those points on which the directive force is very much diminished, they con-
tinue to give satisfactory indications which compasses of inferior workmanship would
wholly fail to do.
The observations of horizontal force were made by vibrating a small flat lenticular
needle 2f inches long and ^ inch broad, fitted with a sapphire cap, on a pivot of its own,
made to screw into the socket of the pivot of the Standard Compass, and comparing the
time of vibration with that of the same needle vibrated on shore.
The observations of vertical force were made by vibrating a dipping-needle of 2f
inches, placed in the position of the compass, the needle being made to vibrate in a
vertical plane at right angles to the magnetic meridian. The observation might of
course be made by vibrating the needle in the plane of the meridian and observing the
dip ; and in low dips that method is probably the best. In so high a dip as that of
England, vibrations in the east and west plane are sufficiently accurate, and enable us
to dispense with observations of dip.
In the selection of these instruments it has been found of great importance that they
should be light, portable, easily and quickly fixed in position, capable of being placed
in the exact position of the compass, should admit of observations being made quickly
and in rough and boisterous weather, and should be such that each separate observation
should give a useful result.
When the observer can command favourable circumstances of observation, as in the
case of observations made in a ship on the stocks, it is possible that instruments of
greater nicety may give more exact results, but for the ordinary observations which can
be made in the process of swinging a ship, we have every reason to be satisfied with the
results obtained from the instruments we have described.
As the formulae made use of in the reductions are nowhere published except in the
‘ Admiralty Manual,’ it seems necessary here to give them with a brief indication of the
manner in which they are obtained.
The effect of the iron of a ship on the compass-needle is assumed to be due partly to
the transient magnetism induced in the soft iron by the magnetism of the earth, and
partly to the permanent magnetism of the hard iron. Simple physical considerations
show that the components of the first in any three directions in the ship are linear
functions of the components of the earth’s magnetism in the same directions, the last is
expressed by constant forces acting in the same three directions.
If, therefore, the components of the earth’s force on the compass be X in the direc-
268 STAFF COMMANDER EVANS AND ME. A. SMITH ON THE MAGNETIC
tion of the ship’s head, Y to starboard, Z vertically downwards or to nadir, and if the
components of the ship’s permanent magnetism in the same directions be P, Q, and R,
and of the total force of earth and ship in the same three directions X', Y', Z', then
Ship’s force to head =X'— X=«X+JY+cZ+P, . . . . (1)
Ship’s force to starboard =Y'—Y=^X+^Y+/Z+Q, (2)
Ship’s force to nadir =Z' — Z==</X-f-/2Y+£Z+R, (3)
a , b, c, d, e, f, g, h, k being coefficients depending on the amount and arrangement of
the soft iron of the ship. These are Poisson’s fundamental equations, first given in the
Memoires de l’lnstitut, tom. v. p. 533.
To adapt these formulae to observation, let
H be the earth’s horizontal force,
£ the easterly azimuth of the ship’s head measured from the correct
magnetic north ;
6 the dip.
Then X= H cos £, Y= — H sin £, Z = H tan 6.
Substituting these values, and dividing (1) and (2) by H, i. e. taking the earth’s hori-
zontal force at the place as unit, equations (1) and (2) become
Ship’s force to head =^77^ —a cos£— b sin£-J-ctan0-j-^- • • • (4)
Ship’s force to starboard=^j^ =d cos £— e sin £+/’ tan • • • (^)
Dividing (3) by Z, i. e. taking the earth’s vertical force as unit, we have
Force of earth and ship to nadir = cos £ sin £+ 1 ... (6)
r Z tan 6 ’ tan 9 ’ Z
If we resolve the forces (4) and (5) in the direction of the magnetic north, we shall
find, besides periodical terms, one non-periodical term — which therefore represents
the mean force of the ship to North, and therefore H=XH, is the “mean
force to North,” or the mean value of the northern component of the force of earth and
ship.
If we take the “ mean force to North,’ or aH. for unit, or, in other words, divide by aH,
we derive from (4) and (5) the following expressions for the force of earth and ship to
North and to East respectively, viz.
H' pos 8
ToNorth=— jj-=l-fS8cos£— 6sin£+2)cos2£— (Esin2£, ... (7)
To East =^^-8=2t+SSsin£+ecos£+2)sin2£+(Scos2£, ... (8)
in which H7 is the directive force of earth and ship on the needle, b the deviation.
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 269
*=l+“-±£, Sf=±A,
®= «=*£* e=‘(/tan.+g).
From equations (7) and (8) we obtain
, v 31 + 33 sin £ + (£ cos £ + ® sin 2£ + (5 cos 2£ SC)\
an 1 + 33 cos £— CE sin £ + 2) cos 2£— (S sin 2%’
whence if £' be the azimuth of the ship’s head measured from the direction of the dis-
turbed needle so that %'=% —
sin &=9l cosd+93 sin £'+($: cos£'+T> sin (2£' +&)+($; cos(2£'-|-&). . . (10)
If the deviations are small, we have approximately
S=A+B sin£'+C cos£'+D sin2£'+E cos2£', (11)
in which A, B, C, D, E are (nearly) the arcs of which 9t, 93, (5, 2), (S are the sines.
The term 93 sin £' + (S cos £' may be put under the form \/932+(£2 sin (£'- \-a ), in which
a, called the starboard angle, is an auxiliary angle such that tan a=|^ •
If the soft iron of the ship be symmetrically arranged on each side of the fore-and-aft
line of the ship through the compass, then
4=0, d= 0, /= 0,
91=0, <g=0,
A=0, E = 0.
R •
If we put |«,=l+^+^5 the expression of the nadir force of earth and ship in terms
z
of earth’s vertical force as unit, is
Nadir force = |=t-£1cos?-^sin?+f., (12)
If the ship heels over to starboard an angle i, 93 and 5) (0r B and D) remain unaltered ;
and representing the altered values of 91, (5 and Cs by 9tf, (5t, and ($t, we have
a‘=3t-V*’
s.=G- ($ + £-l) tan i
The alteration in 9t and (£ may generally be neglected ; that in 6 is often of great
importance. The quantity %= 1^ tan 6 is called the heeling coefficient, and
represents the degrees of deviation to windward, or the high side of the ship, produced
by a heel of one degree when the ship’s head is North or South by the disturbed compass.
270 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
The effect of the coefficients on the deviation is most easily seen by considering the
effect of the derivative coefficients X, 91, 93, 6, 2), ($, and of the heeling coefficients, which,
for convenience of reference, are here arranged in a tabular form. These are as follows : —
a + e .
is a factor generally less than 1, giving the northern component of the mean
directive force on the needle, or “ mean force to North.”
d—b
9t=-2^ (approximate value in degrees =A) is the constant term of the deviation; its
real value is 0 when the iron is symmetrically placed on each side of the
compass, and it is not in general distinguishable from an index error of the
compass, or an error in the assumed variation of the compass (declination).
93 =^ctan 0+ (approximate value in degrees =B) is the maximum of semicircular
deviation from fore-and-aft forces ; - tan 6 arises from soft iron ; from
aH
hard iron.
Q
(5=^/tan 0-\- g^ (approximate value in degrees =C) is the maximum of semicircular
deviation from transverse forces ; tan 6 arises from soft iron, and is zero if
the iron is symmetrically arranged ; ^g from hard iron.
v/932+(52 (approximate value in degrees =>/ B2+C2) is the maximum of semicircular
deviation.
is the tangent starboard angle, or of angle measured to right of fore and aft of line of
ship, in which the force causing the semicircular deviation acts.
2) = (approximate value in degrees =D) is the maximum of quadrantal deviation
from soft iron symmetrically placed.
— 1^ =~ is the part of 2> arising from fore-and-aft soft iron.
® 1^ = — A is the part of 2) arising from transverse soft iron.
($, = (approximate value in degrees =E) is the maximum of quadrantal deviation
from soft iron un symmetrically placed.
tan is the heeling coefficient, or the deviation to windward in degrees
for one degree of heel when ship’s head North or South by disturbed
compass.
^2) + ^— 1^ tan 0 is the part of heeling coefficient from transverse soft iron.
- — i j tan 6 is the part of heeling coefficient from vertical soft iron, and vertical force
of hard iron.
9 is the increase or decrease of vertical force above or below mean when ship’s head is
tanS North or South.
CHAEACTEE OF THE AEMOUE-PLATED SHIPS OF THE EOYAL NAVY. 271
?+- H tan 6 =93 H,
^+1 H' tan ^=S5,H'
are the equations for determining c and P separately when S3 has been determined in
two different latitudes ;
(St-dg
A i—i' ' i—i' ’
7=SSH— tan 6
K A A
are equations for determining c and P separately when observations have been made
in one geographical position, but on two different angles of heel ;
®= i^cos£-(l + ©)cos£,
©= sin £'+(!-$) sin £
are equations for determining SB and (5 by observations of deviation and horizontal force
on one azimuth of the ship’s head, X and 3) being known or, estimated.
There is a physical representation of Poisson’s fundamental equations so simple, and
which gives us so great a power of estimating the effect on the compass of different
arrangements of iron in a ship, as well as of tracing to their cause any peculiarities in
the observed deviation, that it seems desirable, before entering on the peculiarities of
structure and deviation in armour-plated ships, to explain this representation, and to
show how it explains the phenomena of deviation.
If an infinitely thin straight rod of soft iron be magnetized by the induction of the
earth, the effect will be the same as if each end became a pole having an intensity pro-
portional to the component of the earth’s force resolved in the direction of the rod, and
to the section and capacity for induction of the rod.
Let us now suppose nine soft iron rods placed as Plate X. It will be seen that for
each rod we must distinguish the two cases, that in which its coefficient is +, and that
in which it is — . It will also be seen that in the three cases, viz. —a, — e, —k, in
which the rod passes through the compass, we may consider both ends as acting, but
that in other cases it is convenient to consider only the action of the near end, and that
the far end is at an infinite distance.
The rod a, it will be observed, can only be magnetized by the component X, b only
by Y, and c only by Z ; and if we call aX, bY, and cZ the force with which these rods
attract the north end of the needle, and if we suppose, as we are at liberty to do, the
mdccclxv. 2 p
272 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
rods being imaginary, that they exercise no action on one another, a , b , and c will produce
a force to head
=aX+bY+cZ ;
so d , e, and /will produce a force to starboard
=dK+eY+fZ,
and g , h, and k will produce a force to nadir
=#X+AY+£Z.
By comparing these results with Poisson’s formulae, we see that for the effect of the
soft iron of the ship, however complicated its arrangement may be, we may substitute
the nine soft iron rods.
The quantities P, Q, E in the general equations may be conveniently represented by
three bar-magnets, placed in fixed positions in the ship ; P attracting the north end of the
compass-needle to the head, Q to starboard, and E to nadir.
Very simple considerations will show us that the two rods a and e will increase the
directive power on the needle in the proportion of l + ~7y~ : 1? and that the other seven
rods, as well as the permanent forces P, Q, E, will not affect the mean directive force.
Simple considerations will also show that a and e will produce a deviation,
^sin2£=Dsin2£
nearly. Like considerations will show that c and P will produce a deviation,
C-Z^T sin £ = ^ tan 0 + ~ ^ sin £'=B sin £'.
Also that f and Q will produce a deviation,
/Z + Q. y. ( f QA y. ^ y.
cos ^ tan^-f-g ) cos £'=C cos
The other less important terms, as well as the heeling error, may be obtained in the
same manner.
DISCUSSION OF THE TABLES.
At the risk of some repetition it may be convenient to give here a brief explanation
of the quantities tabulated.
The first five quantities, A, B, C, D, E, are the “approximate coefficients” which
give the deviation of the compass on every course by means of the expression
S = A+ B sin £ + C cos £ + D sin 2£ + E cos 2£,
in which & is the deviation, the azimuth of the ship’s head measured eastward from
the direction of the disturbed needle, A, B, C, D, E being expressed in degrees and
minutes.
This expression is sufficiently accurate for deviations not exceeding 20° ; for larger
deviations, the exact expression for the deviation given in the preceding part of the
CHARACTER OF THE ARMOUR-PLATED SHIPS OE THE ROYAL NAVY. 273
paper requires the use of the “ exact coefficients ” 9(, S3, (5, 2), (S, which are not ex-
pressed in degrees and minutes, but are nearly the sines of the corresponding angles
A, B, C, D, E.
For the purpose of this discussion we may confine our attention to A, B, C, D, E.
A is the “ constant part of the deviation.” A real value of A can only be caused by
elongated horizontal masses of soft iron unsymmetrically arranged with reference to the
compass, and would be the same in all parts of the globe. An arrangement of hori-
zontal soft iron rods such as that in fig. 1 would give a positive value to A and no
other term in the deviation. This, however, is not an arrangement which would occur
on shipboard.
Fig. 1. Fig. 2.
A soft iron rod such as that in fig. 2 would give -f A to the starboard compass, com-
bined with +E; and — A, combined with — E, to the port compass.
This arrangement is not unfrequent in the relative positions of the spindle of the
steering-wheel and the binnacle compasses placed near it for the guidance of the
helmsman.
In compasses placed in the middle line of the ship such an arrangement is improbable,
and in such case A has probably little or no real value. An apparent value may, how-
ever, be given to A by index-error in the compass on board, index or other error in the
shore compass with which it is compared, or error of observations generally.
When the ship heels over, an elongated horizontal mass of iron, which was symme-
trically placed from being below the compass, as the screw-shaft or the keel, is thrown
to one side, and an A may then be introduced caused by and proportional to the angle
of heel ; but this has not been found of sufficient amount to require attention in
practice.
The terms B sin £'+C cos £' make up together what is called the “semicircular devia-
tion B depending on fore-and-aft forces, and having its zero when the ship’s head is
North or South, its maximum when it is East or West ; C depending on transverse forces,
and having its zero when the ship’s head is East or West, its maximum when it is North
or South.
B consists of two parts, one a coefficient arising from vertical induction in soft iron
before or abaft the compass, and being multiplied by the tangent of the dip and a factor
- hereafter explained ; the other a coefficient arising from permanent magnetism of the
2 p 2
274 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
hard iron in the ship acting in the fore-and-aft line, and multiplied by the reciprocal
of the earth’s horizontal force, and also by the factor ^ . The last part may be considered
as itself consisting of two parts ; one, of the subpermanent magnetism induced while the
ship was building by the vertical component of the earth’s force, and which probably
bears some relation to the transient magnetism induced by the same vertical component ;
another, of the subpermanent magnetism induced while the ship was building by the
headward component of the earth’s horizontal force.
C theoretically consists of similar parts acting towards the sides of the ship ; but as
the iron may in general be considered as symmetrically arranged on each side of the
compass, the value of C is probably, in all cases when the ship is upright and the com-
pass is amidships, to be attributed to subpermanent magnetism induced while the ship
was building by the transverse component of the earth’s horizontal force. The part of
B consisting of transient induced magnetism varies as the tangent of the dip. The other
part of B and C vary inversely as the earth’s horizontal force. As regards changes
which take place after launching, without a change of geographical position, there are
differences between the several parts of B and C which require notice.
When the ship is launched, notwithstanding that her head is no longer kept in one
fixed direction, the forces which cause the two first-mentioned parts of B still act in
precisely the same direction as before, and these two parts probably undergo little
change.
With the third part of B and the whole of C the case is very different. The forces
which cause these parts cease to act in the same direction as at first. If the vessel is
allowed to swing at her anchors, or is under sail or steam, she will probably on an
average be nearly as much on one point as on another ; or, which would come to nearly
the same thing, if she is lying in a tideway she may be alternately for six hours in one
direction and for six hours in the opposite direction. A great portion of the C and of
that part of the B which arose from horizontal force thus become dispelled.
The symmetry which gives C its character ceases the moment the ship heels. An
addition is then made to C proportional to the angle of heel, and this addition consists
in fact of two parts, corresponding to the two parts of B which, as we have seen, do not
exist in the original C, viz. a part consisting of transient magnetism induced by the
vertical force, and a part consisting of subpermanent magnetism induced by the same
force. These will be more conveniently considered when we come to discuss the heel-
ing error.
The semicircular deviation may be put under the form \/B2+C2sin(^'+a), in which
v/B2-J-C2 represents the maximum of semicircular deviation, a f tan «= -j the angle to
the right of the ship’s head of the force causing this deviation; for convenience, these
two quantities are tabulated in the eleventh and thirteenth columns.
The terms D sin 2£'-}-E cos 2£' make up what is called the “quadrantal deviation.”
CHAEACTEE OE THE AEMOTTE-PLATED SHIPS OP THE EOYAL NAVY.
275
This can only be caused by horizontal induction in soft iron. E can only be caused by
horizontal induction in soft iron unsymmetrically distributed, but of any shape ; an
E may therefore be caused by the compass being placed out of the midship line and
exposed to the influence of spherical or cylindrical masses, such as the iron gun-turrets
of modern war-vessels.
D, which in ordinary cases is always +, is caused by horizontal induction in soft iron
arranged according to one or other of the following types : —
Pig. 3. Pig. 4.
+ a
\\a
In the figures -f -a represents masses of soft iron entirely before or entirely abaft the
compass, as engines, boilers, funnels, iron masts, &c.; — a represents soft iron extending
through the position of the compass, as the keel and hull of the ship, the screw-shaft,
armour-plating, &c., the effect of the latter in almost all cases exceeding that of the
former, so that a is in general negative; — e represents the effect of all the transverse
soft iron, as the bottom of the ship, the iron decks (except where interrupted by hatch-
ways near the compass), iron deck beams, and the engines, boilers, &c. ; -\- e represents
the masses of iron, comparatively few in number, which lie to one side of the compass,
as decks where the compass is in or over a hatchway, occasional guns, davits, & c. In
every ship which has been examined, the effect of the transverse iron extending through
the position of the compass exceeds that of any masses of iron wholly on one side, and
e is negative and greater than a ; and as 2 = ^^, 2), and consequently D, are in almost
all cases + .
D and E do not change with a change of geographical position.
In almost all cases in iron-built ships, not only is the direction of the needle directly
affected by the iron of the ship, but a further prejudicial effect is caused by the soft iron
diminishing the mean directive force of the needle, and so indirectly increasing the effect
of all disturbing forces. This is shown by the factor X, which gives the mean value of
the directive force, or rather of the northern component of the directive force in the
ship, and which is almost always less than unity, the force on shore being considered as
unity.
The cause of this diminution will be seen by figs. 3 & 4. In fig. 4 a little considera-
tion will show that both —a and — e diminish the directive force. In fig. 3 +a in-
276
STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
creases the directive force, — e diminishes it; but as — e always exceeds -\-a, the result
is a diminution on the whole.
The expression for X in terms of a and e is
X = l +
a + e
The tabulated values of X are obtained by comparing the terms of vibration of a hori-
zontal needle vibrated in the position of the compass in the ship and also on shore;
X does not change with a change of geographical position.
The determination of 3) and X gives us the means of determining the two parts a and
e, and also the two parts of which D is composed, separately ; and these are accordingly
tabulated.
The preceding are the only coefficients which affect the compass when the ship is
upright ; but when the ship heels over, new disturbing forces are called into play, caused
by arrangements of soft or hard iron of one or other of the following types: —
Fig. 5.
— e represents, as before, the transverse soft iron, which will evidently, as the ship heels
over, produce a force to windward, or the high side of the ship, on the north end of the
needle. If the rods -\-7c and — k represent soft iron, then -| -k gives a force acting down-
wards on the north end of the needle, which, as the ship heels, becomes a force to wind-
ward ; — k a force acting upwards, which, as the ship heels, becomes a force to leeward.
The permanent magnetism of the ship will generally act downwards if the compass is
over the end which has been South in building, upwards if over the end which has been
North in building. The amount of the two forces may be ascertained by vibrating a
dipping-needle on shore and in the ship with her head in certain positions. The pro-
portion of the mean vertical force on board to the vertical force on shore is denoted by
the coefficient p, which is tabulated for those ships in which the observations have been
made.
From the values of 3) and X we obtain by a simple formula, viz. ^3) + 1^ tan 6 1°,
the “ heeling coefficient to windward,” or the deviation to windward caused, when the
ship’s head is N. or S. by compass, by an angle of heel of 1°. When this coefficient has
a negative sign it indicates a deviation to leeward. The values of the heeling coefficient
so deduced are tabulated. The value changes with a change of geographical position.
From the values of p, 3) and X we may also determine how much of the heeling error
arises from the transverse soft iron represented in the figures 3, 4 & 5, and how
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 277
much from the vertical soft iron and the hard iron, the first = ^2)+ 1^ ^an ^ *°’
the second =■ tan H°; and these two parts are tabulated in the next columns.
If we have not an opportunity of observing the vertical force on a sufficient number
of points to obtain its mean value, the values observed will be affected by soft iron
represented by the rod g , in the following figure : —
Fig. 6.
the value of [m on any azimuth £ being in fact increased by + cos where 6 is the
dip. It is therefore convenient to know the values of q or and these are also
^ ^ tan 0
tabulated ; g does not change with a change of geographical position.
In comparing the heeling error when the ship’s head is North or South, we must
beware of falling into the error of confusing the two senses in which these words may
be used. It may seem most natural to suppose the ship’s head to be North or South
when upright, and that she is then heeled over without altering her direction. In that
case we should have (nearly)
Heeling error head North : heeling error head South : : 1 — 25 : 1 +93.
In fact the heeling error is nearly inversely proportional to the directive force on the
needle.
But this is not the sense in which the term is generally used. In general we suppose
the ship swung when heeled to starboard and again when heeled to port, and the devia-
tions tabulated in the usual way, according to the ship’s azimuth by disturbed compass.
In this case, which is the simplest mode of considering the error for the purpose of
correction, the heeling error, head North, will only differ from the heeling error, head
South, by reason of the quantity g , i. e. by reason of the difference of the vertical and
not of the horizontal forces in the two positions.
The importance of the heeling error, owing to its large amount in certain ships, will be
seen in the discussion of the values given in the Tables ; and the importance of being
able to determine it by observations easily made, and without the necessity of actually
heeling over the ship, can hardly be overrated.
We are now in a position to consider the numerical values of the coefficients given in
the Tables.
278 STAFF COMMANDER EVANS AND ME. A. SMITH ON THE MAGNETIC
Constant Deviation.
A.
The values of A, when the compass is placed in the middle line of the ship, and when
the deviations have been observed with every care, are always so small, that the values
which appear in the Tables may be considered rather as errors of adjustment and
observation than as real values. In fact it may be inferred that in all cases where the
compass is in the middle line of the ship, we may consider A as zero. It results from
this, and is important in practice, that we may safely take the mean of the compass
bearings of any object, on four or more equidistant compass courses, as the correct
magnetic bearing ; observing, however, that if we observe on four points only, and D be
large, these ought to be either the cardinal or the quadrantal points.
Semicircular Deviation ,
B sin C cos g.
The points which require attention are, —
1. Its original value and its connexion with the direction of the ship in building, and
the position of the compass in the ship.
2. The changes which take place after launching.
3. The subsequent changes.
4. The changes which take place on a change of geographical position.
1. In wood-built ships, as maybe seen by an inspection of the Deviation Tables given
in the work of the late Captain E. J. Johnson, R.N., on the deviation of the compass, the
direction of the force causing the semicircular deviation is in northern latitudes nearly
towards the ship’s bow. In iron-built ships it is nearly to that part of the ship which was
South in building ; or, in other words, the starboard angle as given in the Tables, is nearly
the same as the azimuth of the ship’s head to the East of South in building ; thus, —
Starboard angle, or direction
Direction of bead in building. of semicircular deviation.
Orontes . . N. 66° W. or S. 246° E. 235°
Tamar . . . West or S. 270° E. 279°
The case of the armour-plated ships is an interesting exception to this rule. Such
ships are generally plated after launching, and in a different position from that of
building. In these ships the angle of the semicircular force is generally intermediate
between the angle of the ship’s head to the East of South in building, and the like angle
in being iron plated ; thus, —
Warrior .
Black Prince
Defence .
Resistance
Valiant
Direction of bead
in building.
N. 3 E. or S. 177 E.
S. 20 E. 20
S. 47 W. 313
Direction of bead
in plating.
N.W. or S. 225 E.
South. 0
S. 19° E. 19
West.
270 generally to westward
Direction of
Semicircular
Deviation.
195
8
0
f 313
* 1282
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 279
From these results we may infer that the process of plating an iron ship in the direc-
tion opposite to that of building will always produce a diminution, which in some
cases may become a reversal of her semicircular deviation ; and that by duly taking
advantage of this circumstance, the deviations of iron-plated ships may be brought within
manageable limits.
The Tables show, as might have been anticipated, the much larger amount of the
deviation in the steering and main-deck compasses than in the Standard Compass, and
the advantages to be derived from a judicious selection of a place for the compass ; un-
fortunately even in the case of the Standard Compass the choice of position is so limited
by the exigencies of the arrangements for working and fighting the ship, that the devia-
tions in these compasses are generally larger than could be wished.
2. After launching, and when the vessel is swinging at anchor, or sailing or steaming
in various directions, the values of B and C generally diminish rapidly ; and this change
would no doubt be accelerated by the vessel being exposed to blows or jars in a position
different from that of building.
The following cases show a rapid change of B and C after launching. The most
instructive have been selected from the Tables, but the elaborate series of observations
made in the Great Eastern (Phil. Trans. 1860) are the most conclusive, as that ship was
in every respect prepared for sea, and the observations are strictly comparable throughout.
H.M.S. Achilles, built in dry dock at Chatham, and fully plated there also, head
S. 52° E., floated out of dock 24th December 1868, and moored head and stern in
the River Medway, head S. 62° E. In March 1864, after taking in steam machinery,
the ship made a short trial trip down the river, and then returned to the former
moorings, but with her head secured in the opposite direction, or N. 62° W.
Equipment and fittings completed by October 11th, when the head was shifted
round to S. 55° E., and on the following day steamed to Sheerness and commenced
sea service.
23.
1863.
Dec.
23. — In dock at Chatham
+ ■464
+ •323
1864.
Sept. 26. — Complete for sea, head N. 62° W. . .
+ •377
+ •037
Oct.
11. — Complete for sea, head S. 55° E. . .
+•355
+ •062
Oct.
13. — Swinging at anchor, Sheerness . . .
+ •362
+•047
Dec.
5. — At Plymouth, after 25 days in dock,)
- + *361
+ •123
head S. 79° E J
H.M.S.
Royal Oak, wood-built ship, iron-plated in dock at Chatham,
head S. 49° E„
1863.
Mar.
19. — Floated out of dock
+ •253
+ •287
April 11. — Swinging at anchor, River Medway .
+ •231
+ •197
June
2. — Swinging at anchor, River Medway .
+ •248
+ •128
1864.
Jan.
8. — Swinging at anchor, Plymouth .
+ •218
+ •172
The example of the Achilles is very instructive. The large value of (S+’323 giving
mdccclxv. 2 Q
280 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
a C of 19°, which was caused by the ship having been built, plated, and moored with the
starboard side South, is reduced to +‘037 or 2° 10' by lying for six months with the
port side South. This amount does not alter materially while the ship is allowed to
swing, but when she is twenty* five days in dock with the starboard side South, it suddenly
rises to + T23 or 7°.
SB, it will be observed, changes much less at first, and hardly changes at all afterwards ;
this difference must be attributed in part to this, that while the whole of (5 is to be
attributed to subpermanent magnetism arising from horizontal induction in transverse
hard iron, a large part of the original S3 was probably caused by the transient magnetism
arising from vertical induction in soft iron, and a further part by the subpermanent mag-
netism arising from vertical induction in hard iron, so that possibly not more than TOO was
caused by the subpermanent magnetism arising from induction from the headward com-
ponent of the horizontal force, nearly the whole of which may have been removed by six
months’ reversal of her direction, so as to leave little room for subsequent change of S3.
In connexion with this part of the subject we may observe that the same circumstances
which cause the transient magnetism arising from horizontal induction in transverse
iron (—&) to be greater than the transient magnetism arising from horizontal induction
in fore-and-aft iron ( — a), lead us to expect that the subpermanent magnetism arising
from horizontal induction in transverse hard iron ((5) will be greater than the subper-
manent magnetism arising from horizontal induction in fore-and-aft hard iron (changing
part of S3), and that consequently we should expect the relative changes of 6 which take
place on a change of direction to be greater than those of S3, and this will be found to
be verified in almost all cases, except when the ship has been built nearly North and South.
3. After a certain time, which may be roughly estimated at a year after launching,
this process seems to stop, and the values of B and G remain remarkably permanent.
The former paper* contains numerous examples of this in ordinary iron-built ships.
This will appear also from the following instances of the iron-plated ships.
Standard Compass.
a <£.
Warrior.
September 1861 . . .
-•449
-•124
October 1861 . . . .
-•409
-•092
July 1862 ....
-•321
-•114
June 1863 ....
—-■317
— T32
July 1864 ....
-•311
-•054
October 1864 ....
-•307
-•072
Defence.
February 1862 ....
+•464
+ •005
March 1863 ....
+ •379
-•034
December 1863 . . , .
+ •403
-•016
April 1864 ....
+ •391
f
©
©
-a
October 1864 ....
+ •379
-•034
* Philosophical Transactions, Part II.
I860.
CHARACTER OR THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 281
Standard Compass.
33.
e.
Black Prince.
November 1861
. + -422
+ •058
September 1862 . .
. -f-383
+ •074
July 1863 . .
+ •384
+ •067
April 1864 . .
, +-389
+ •086
October 1864 . .
. +-349
+ •050
Resistance.
August 1862 . ,
, +T49
-•158
June 1863 . .
. +T52
-•138
December 1863 . .
, +T06
-•120
December 1864
. +-065
-•153
It will be remembered in the foregoing examples that the ships have been frequently
subjected to the strains in docking, trials, in gales of wind, and at high rates of speed,
and especially to concussions from the drilling and firing their heavy ordnance.
A striking example of the permanency of the magnetism of an “ old ” iron ship after
severe concussion is afibrded in the case of the Adventure troop-ship built in 1854.
This ship, in the course of foreign service during a fog, struck on a rock with sufficient
force to tear away and crush in 20 feet of the stem and bow under water ; appended
are the coefficients observed before proceeding on the foreign service, and after the
injuries sustained had been repaired in dock.
1862. April 26th . . . = U73 + -186
1862. October 28th , . — -07X + T86
An equally close agreement will be fonnd, on reference to the Tables, to exist in the
other magnetic coefficients of this ship ; the exact accordance of the numerical values is
of course accidental, but is conclusive as to the great wear and tear and rough usage an
old iron ship can undergo without her magnetic conditions being changed.
4. The determination of the proportion of the semicircular deviation, or rather of B,
which arises from vertical induction in soft iron, and that which arises from the perma-
nent or subpermanent magnetism of hard iron, is a matter of great interest. Theore-
tically it may be determined in two modes, either by observing the deviation in two
different magnetic latitudes, or by observing the deviation with the ship upright and
heeled over. Unfortunately there is a great want of observations under these circum-
stances. The deviations of the iron-plated ships, given in the Tables, were carefully
observed both at Lisbon and Gibraltar, but the difference of latitude between either
place and England is too small, and the change in the subpermanent magnetism too
great to enable us to derive any very certain results from these observations.
The difficulty of heeling a large ship is so great that few observations except in an
upright position can be expected ; we owe, however, to the zeal of the officers in com-
mand of the Warrior*, Black Prince, and Defence, that these ships were swung at
* Magnetip science is footed to the Honourable Captain Cochrane of Her Majesty’s Ship Warrior, for the
interest he has evinced,, and the assistance he has rendered in obtaining poprplete records of that ship ; and
2 q 2
282 STAFF COMMANDER EYANS AND MR. A. SMITH ON THE MAGNETIC
Lisbon upright, and heeled about 7° to starboard and to port. The agreement of the
values of the coefficient ~ derived by the different methods is not very satisfactory, and
it can only be considered as a rough approximation to the truth.
From the equation for comparison of semicircular deviation in different latitudes
?+Htan^=9BH.
P c_
A* A
Warrior .... — ‘471 +‘058
Black Prince . . . +‘061 +-142
Defence .... +‘206 +‘079
Resistance. . . . —330 + T90
From heeling-error formulae. jj.
A
Warrior +T08
Black Prince +*181
Defence +T19
Taking the mean of the several values in the ships.
Original
value of B.
c
a
Part of B
from soft iron.
Part of B
from hard iron.
Warrior
-241
•083
+ 12
— 3&1
Black Prince
+ 23
•161
+ 23
0
Defence
+ 25f
•099
+ 141
+ 114
Taking the present values of B
in the ships.
B.
C
Part of B
Part of B
k
from soft iron.
from hard iron.
Warrior
-17
•083
+ 12
-29
Black Prince
+ 19
•161
+ 23
— 4
Defence
+ 21
•099
+ 141
+ 61
And in any other magnetic latitude for which the horizontal force is H, the hori-
zontal force in England being 1 and the dip 6, we should have
O
29 °
Warrior .... B=— jj +4f tan 6.
Black Prince. . . B= — g + 9^ tan 0.
o
Defence .... B= ^|+5§tan0.
also to William Mates, Esq., Master of Her Majesty’s Ship Defence, for a valuable series of observations made
in that ship, and for his exertions in obtaining results in several ships of the Channel Squadron.
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 283
Quadrantal Deviation, D sin 2£'+E cos 2£\
Mean force to North XH.
The Tables show that the values of E when the ship is upright and the compass in
the midship line, give no certain indication of any real value. The more accurate the
instrument, and the more careful the observations, the smaller E generally is.
When the compass is not in the midship line the case is different ; an E may then
have a considerable value. Instances of this will be seen in the deviations of the Royal
Sovereign, the peculiar construction and fittings of which ship made it necessary to
place compasses considerably out of the midship line, and with gun turrets placed
diagonally to them.
At the steering wheel on upper deck .
At the steering wheel in captain’s cabin
(Port side
Forward on lower deck
(Starboard side
. E= — 9 14
. E= — 5 10
. E=+4 38
. E= — 4 42
It will easily be seen that a +E would be caused by a gun turret in the first and
third quadrant relatively to the compass, and a — E by a turret in the second and
fourth. The close agreement of the numerical value of E in the two last examples,
with the difference in their signs, is striking.
The value of the E introduced by the ship heeling by an angle i to starboard being
£±£?-
2A
and both c and g being generally positive, we should expect a — E when the ship heels
to starboard, a +E when she heels to port, and this is the case in the few instances
we have in the Tables.
E.
Warrior. — Standard Compass . .
Black Prince. — Standard Compass .
Defence. — Standard Compass
o o
\n
to
starboard
-0
45
m
to
port . .
+o
59
m
to
starboard
-1
25
to
port .
+ 1
50
n
to
starboard
-0
05
.7*
to
port . .
+ 1
50
D.
As regards D, the most important point is its magnitude in different positions in ships
of different classes.
The usual or average value of D has greatly increased since the publication of the
Paper in 1860. In that paper it was observed that a value for this coefficient not
exceeding 4° and ranging between that amount and 2°, might be assumed to represent
284 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
the average or normal amount in vessels of all sizes, and in only two vessels mentioned
in that paper did D exceed 5°.
In the iron-built armour-plated ships its average amount in the Standard Compass is
about 7°, in the steering-compass about 10°, and in the main-deck compass about 12°.
In the wood-built iron-plated ships the value of D is small.
The following Table gives the value in different ships.
Warrior.
Black
Prince.
Achilles.
Defence.
Resistance.
Hector.
Valiant.
Royal Oak
(wood-
built).
Standard compass
Starboard steering
Main deck
+ 8 27
+ 11 56
+ 11 43
+ 7 38
+ 10 32
+ 13 16
+ $ 58
+ 8 51
+ 12 13
+ 7 o
+ 10 16
+ 14 35
+ 6 17
+ 8 28
+ 14 0
+ 5 24
+ 8 24
+ 9 47
+ 4 54
+ 6 52
+ 8 05
+ 3 09
+ 1 47
+ 1 28
The large amount in the Standard and Steering Compass of the Warrior is doubtless
owing to the rifle tower which is immediately before them, and which gives a -f a. The
small comparative values in the Hector and Valiant to the iron-plating being extended
from end to end in the ship giving a — a, and the absence of a complete transverse armour
bulkhead, the existence of which in the Defence and Resistance, as well as in the
Warrior and Black Prince, give large — e, and consequently large deviations in the bin-
nacle and main-deck compasses.
Between the Resistance and the Defence there is a remarkable difference. These are
nearly sister ships, but with this difference, that from the different position of the mizen-
mast in the two ships their standard and steering compasses are very differently placed
with reference to the transverse armour bulkhead. In the Resistance the Standard
Compass is exactly above the bulkhead at a height of 12 feet. The steering-compass is
about 4 feet in front, and the same height above it ; while in the Defence these compasses
are about 20 feet abaft it.
Such a bulkhead, when magnetized at right angles to its plane, will produce a fore-and-aft
force on all points in, or nearly in, the same plane in the opposite direction to the mag-
netizing force. It will therefore, in the case of the standard and steering-compasses of
the Resistance, introduce a —a as well as a — e, while it will produce little or no —a in
compasses placed as in the Defence, and a much smaller — e.
These differences do not show themselves in the value of D, which is in fact less in
the Resistance than in the Defence, notwithstanding the much more powerful action of
the forces which cause it. In order to see them, we must obtain separately the two
parts of the quadrantal deviation D, or the value of a and e. This is done in the fol-
lowing Table:- —
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 285
Warrior.
Black
Prince.
Achilles.
Defence.
Resist-
ance.
Hector.
Valiant.
Royal Oak
(wood-
built).
q, , i / From fore-and-aft induction. . .
" [ From transverse induction ...
+ 06
- I 4
- 2 45
- 2 42
- 5 55
- 3 51
- 2 14
— 1 19
+ 8 24
+ 11 42
+ 9 40
+ 9 44
+ 12 21
+ 9 15
+ 7 11
+ 4 32
Starboard f From fore-and-aft induction. . .
+ 0 14
- 3 47
- 3 47
- 2 17
- 7 53
- 3 23
- 2 59
- 2 7
Steering . . . \ From transverse induction . . .
+ 11 46
+ 14 28
+ 12 43
+ 12 35
+ 16 33
+ 11 49
+ 9 54
+ 3 51
-w- • -j-. ,f From fore-and-aft induction...
am ec y jrrom transverse induction . . .
- 2 35
- 3 9
- 2 10
- 1 02
- 5 58
- 6 56
- 3 51
+15 58
+ 15 36
+ 16 58
+ 15 11
+ 15 54
+ 15 14
+ 5 20
Standard .. | g
+ 002
-112
-079
-•078
-158
-109
-•068
-043
-■256
-•322
-•277
-•278
-•326
-•263
-•214
-143
Starboard fa .
+ ■006
-100
-•103
-•064
— 193
-093
-•085
-•066
Steering . . . \ e
-•340
-■380
-•343
-■348
- 401
-•325
- 281
-122
fa
-•068
-•083
-048
-027
-151
— •176
— 116
Main Deck •!
-•418
-•407
— •434
-•409
-■397
-•380
-160
The conclusions we have drawn will be seen to be supported by this separation. Thus
we see that the Warrior is the only vessel which has a -\-a and a -J-D from fore-and-aft
iron. In the Hector and Valiant the D is comparatively small, because the — a is large,
the — e small.
In the Resistance the two parts, the difference of which makes up the D, are very
much larger than in the Defence, though the resulting value of D is less.
The comparison of the values of D and of a and e in the compasses of the Royal
Oak with those in the compasses of the Hector and Valiant is very instructive. These
ships are nearly alike in dimension, in the arrangement of the iron-plating, and the posi-
tion of the compasses. The Royal Oak has an iron upper deck, but is otherwise wood-
built. The Hector and Valiant are entirely iron-built.
A first inspection of the Table might lead us to infer that the large value of D in the
iron-plated ships is due to the armour-plating at the sides, but the comparison with the
Royal Oak shows this not to be the case. In fact a little consideration will show that,
as regards longitudinal induction, the effect of armour-plating continued from end to end
is to produce a — a ; that, as regards transverse induction, the effect of the parts which
run fore and aft is to produce a small -\-e, and the effect of the transverse parts near
the extremities of the ship to produce a small — e, so that on the whole the tendency is
probably rather to diminish than to increase D. The large value of D in the iron ships
is evidently attributable to the increased amount of transverse iron in decks, bulkheads,
iron beams, and the iron bottom of the ship, the magnetism of which is, as it were, con-
ducted upwards by the iron sides.
X.
The value of X is so closely connected with that of D that it is desirable to consider
them together. In the earlier built iron vessels X was very nearly equal to 1. In the
Rainbow, at four stations distributed along nearly the whole length of the ship, X ranged
from -972 to T003. In the Ironsides, the first iron-built sailing ship, it was ‘917 at
286 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
the steering-compass. In several iron-built ships purchased into the Royal Navy from
ten to fifteen years after Mr. Airy’s observations, X averages at present about -930. In
the iron-plated ships of the present day it ranges from 'TOO to -900.
The following are its values in the iron-plated ships before mentioned.
Warrior.
Black
Prince.
Achilles.
Defence.
Resistance.
Hector.
Valiant.
Royal Oak
(wood-
built).
Standard compass
•873
•783
•822
•822
•758
•814
•859
•907
Starboard steering
•833
•760
•777
•794
•703
•791
•817
•906
Main deck
•757
•755
•759
•782
•726
•722
•862
The large value in the Warrior is evidently owing to the rifle tower, the small value
in the Resistance, as compared to the value in the Defence, to the position of the com-
passes with respect to the armour bulkheads as above described, and with reference to
the armour-plating generally.
Familiarity with the values of 2 and X in vessels of different classes, is of great import-
ance in enabling us to deduce 95 and (§, by observations made without swinging.
The mathematical theory from which the values of 2) and X are derived, supposes
that the transient induced magnetism to which 2 and 1— X owe their values, is instan-
taneously developed, and as instantaneously destroyed or altered as the ship assumes a
new position. This we cannot suppose to be exactly true; but whether the time
required for the soft iron to receive its new magnetic state as the ship swings is appre-
ciable has been a matter of doubt. The opinion of the authors of the Report of the
Liverpool Compass Committee (an opinion entitled to the greatest weight) was, that
an appreciable time was required, and that the value of D in particular might be different
according as the vessel was swung slowly or quickly ; we have not, however, been able
to detect any difference in the values of D which can be attributed to any cause of this
nature.
The most remarkable feature, however, in X and 2 is the change which takes place
with the lapse of time, indicating apparently a change in the molecular structure of the
soft iron by which it becomes less susceptible of induced magnetism. This is shown
clearly in the following Table : —
CHARACTER OE THE ARMOUR-PLATED SHIPS OE THE ROYAL NAVY. 287
1
Standard.
Starboard steering.
Main deck.
X
©
X
©
X
2)
Achilles
T October
1864
•822
+ •121
•777
+ •154
•755
+ •214 |
[ December
1864
•854
+ •116
•819
+ •137
•804
+ •188 |
'November
1861
•716
+ •145
Black Prince. <
September
April
1862
1864
•783
•846
+ •134
+ •137
•760
+ •184
[November
1864
•849
+ •122
•881
+ •144
f February
1862
•822
+ •122
•794
+ •179
•759
+ •254 !
Defence <
1 December
1863
•853
+ •122
•842
+ •180
•810
+ •230
1 April
1864
•857
+ •112
•853
+ •159
•828
+ •233
i
[October
1864
•852
+ •112
•830
•842
+ •230
Resistance ... j
f August
1862
•758
+ •111
•782
+ ■244 !
[ December
1863
•850
+ •122
•880
+ •219
1
[" March
1863
•861
+ •047
Royal Oak ... <
April
1863
•907
+ •061
•887
+ •067
1
[ June
1863
•907
+ •055
•906
+ •031
Dromedary... j
'July
1862
•841
+ •104
|_ December
1862
•861
+ •097
These changes, and particularly that in the value of X, seem far too great, far too
regular, and far too consistent, to be attributed to any cause except some molecular
change in the structure of the iron which, with the lapse of time, renders it less suscep-
tible of induced magnetism. Whether this change is accompanied by any change which
can affect the strength, the liability to oxidation, or any other qualities of the iron, is a
point on which we are not able to offer any information, but we beg to suggest it as a
question deserving a careful experimental investigation.
Heeling Error.
As the heeling coefficient depends partly on vertical induction in transverse iron,
partly on the mean vertical force arising from permanent magnetism and vertical induc-
tion in vertical iron, and as the two conspire when the vertical force of the ship acts
downwards, or when p is greater than unity, and counteract each other when the ver-
tical force acts upwards, or when p is less than unity, we may expect great differences
in the heeling coefficient in different ships. In those which have been built head North,
we may expect a large heeling error in compasses near the stern, and a smaller one in
compasses near the bow, and the converse in ships built head South. This we find to
be the case.
In these cases the uniformity of the heeling coefficients from transverse iron is remark-
able, and they are, as might be expected, all of the same sign ; the differences, it will be
seen, are nearly all in the part which arises from vertical force ; this varies from 1° 6' in
the Warrior to —1° 9' in the Enterprise.
It will be seen that in the wood-built iron-plated ships the vertical force is generally
mdccclxv. 2 R
288 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
diminished. This is doubtless the effect of the iron plating, which acts as a — Jc. No
doubt in iron-plated iron-built ships the effect is the same, and the heeling error is
probably diminished and not increased by the effect of the iron plating. Observations of
vertical force have not been made in the main-deck compasses of these ships ; but pro-
bably there the heeling error would be small, and possibly be a heeling error to leeward.
We must observe that there has not been an opportunity of making an exact com-
parison of the values of the heeling coefficient deduced from theory with those deduced
from actually heeling and swinging the ship. The great amount of labour and time
required to heel a ship of the class we are discussing, and swing her, has prevented such
observations being made in more than a very small number of cases. In the case of
the Warrior, Black Prince, and Defence, advantage was taken of their being heeled at
Class
of
Ship.
Iron
plated.
'July 1862.
Jan. 1863.
Sept. 1862.
Jan. 1863.
April 1864.
Oct. 1864.
Dec. 1864.
Oct. 1864.
ships, , Dec. 1864.
iron- "
' Feb. 1862.
Jan. 1863.
April 1864.
Aug. 1862.
Dec. 1863.
Feb. 1864.
(Jan. 1865
April 1863.
June 1863.
Feb. 1864.
Wood
ships,
ptted. | 1864‘
| June 1864.
1
Iron
ships.
( July 1863.
Nov. 1863.
Sept. 1863.
Feb. 1863.
Feb. 1863.
Mar. 1863.
June 1863.
Name of Ship.
Warrior
,, Lisbon
Black Prince
„ Lisbon
Achilles (Standard aft)
„ (Standard forward),
Defence
„ Lisbon
Resistance
Hector
Valiant
Royal Oak
Prince Consort
Ocean
Enterprise (Iron topsides) . .
Orontes
Tamar
„ (Binnacle over rudder)
Wye
Caradoc
Clyde
Industry
City of Sydney
Direction of Head in
building.
N. 3°E
S. 20° E
S. 51° 40' E. ...
S. 47° W
S.86i°W
S. 20° E.
S. 87° W
Plated S. 49°E
Plated S. 39° W
Plated S. 79° E
Built and plated
S. 56° W.
N. 66° W
West
Probably to E.S.E. ..
Probably to N. by W.
Probably to N.E. . . .
Probably to S. by E.
Probably to W.N.W.
•945
•971
•870
•896
1-217
1-240
1040
•968
1071
1044
•848
•929
•622
1117
1-248
M95
1002
1-275
•859
1-246
+•069
+•106
+•118
+•262
+ 111
+•194
+■210
-•172
-•165
+•138
+•117
+•157
+•176
+ 190
+•120
+•045
+•127
+•038
+ 112
+•152
+ 147
+•294
+•252
Heeling coefficient from
Heeling
coefficient
windward.
vertical
induction
in trans-
verse iron.
vertical
force and in-
duction in
vertical iron.
+0 43
+0 32
+1 06
+0 50
+1 49
+1 22
+1 01
+° 43
+0 48
-0 11
+0 09
-0 05
+0 50
+0 52
+0 43
+0 50
+0 43
+0 49
+0 37
-0 23
-0 18
+0 40
+0 41
+0 27
+0 25
+ 1 29
+ 1 18
+0 51
+0 33
+0 42
+0 08
— 0 03
-0 06
+0 59
+0 30
+0 36
+1 04
+0 45
+0 14
+0 08
+1 18
+0 53
+0 48
-0 03
+0 45
+0 37
+0 11
+0 48
+0 24
+0 23
-0 17
-0 19
+0 07
+0 04
+0 16
-0 24
-0 08
+0 19
-0 34
-0 15
+0 37
-1 09
-0 29
+0 36
+0 28
+ 1 04
+0 31
+0 28
+0 20
+0 42
+0 51
+ 1 10
+0 27
+0 34
+ 1 0
+0 14
+0 01
+0 15
+0 35
+0 47
+1 22
+0 18
-0 23
-0 05
+0 46
+0 45
+ 1 31
CHARACTER OE THE ARMOUR-PLATED SHIPS OE THE ROYAL NAVY. 289
Lisbon for the purpose of cleaning the bottoms, to swing them at the same time, and
the heeling coefficients so obtained correspond very satisfactorily with those obtained
in England from observations of horizontal and vertical force. But, unfortunately, at
present we have no instances in which the horizontal and vertical forces were observed
at the time and place at which the ship was heeled and swung; and it seems very
desirable that the theory should be put to the practical test, though there seems no
reason to doubt that the results of the two methods would agree within the limits of
errors of observation.
9-
g is one of those quantities which it is of importance to be able to estimate with some
approach to accuracy, in order that the value of the mean vertical force, or p, may be
determined by observations of the vertical force made with the ship’s head on one point
only.
The Tables show that this may3 be done ; g, as might be expected, is larger the
nearer the stern the Standard Compass is placed, and is negative in compasses placed
near the bow.
Achilles +‘194
Resistance +T76
Defence +T57
Black Prince +T18
Warrior + -069
Achilles (Standard forward) . . — T72
There are indications of changes in the value of the heeling coefficient and in the
value of g from the lapse of time, corresponding to the changes in the values of
2) and X; but more extended observations are necessary to show the amount and law
of these changes.
To afford a clear view of the general structure of the armour-plated ships, and the
position of the several compasses, profile sketches of these ships are given (Plate XI.),
and it may be deemed of sufficient interest to add a brief description of their general
arrangements as affecting their magnetic characteristics.
The Warrior, Black Prince, and Achilles, of 6100 tons, are types of the largest size
iron-built and iron-plated ships of war ; they are 380 feet long, 58 feet beam, 26 feet
draught of water, propelled by engines of 1250 horse-power, and carry from forty to
twenty heavy guns. 3750 tons of iron is used in the construction of the hull, which
varies in thickness from 1^ inch near the keel to f inch behind the armour-plates.
For the Achilles 1200 tons of iron 4^ inches thick was employed for the armour-plating.
The Hector and Valiant of 4100 tons, and the Defence and Resistance of 3700 tons,
are types of the medium and smaller-sized iron-built and iron-plated ships of war. In
the general features of construction they are similar to the Warrior, Black Prince, and
Achilles ; all are frigate-built, or with a main deck for the principal battery of guns,
2 r 2
290 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
and the only wood used in the hulls, with the exception of teak-wood backing to the
armour plates, is for the surface covering of the iron decks, and for the personal
arrangements and accommodation of the crews.
In the Warrior, Black Prince, Defence, and Resistance, the armour-plating of 4^-inch
iron is not continued to the bow or stem, but where it terminates is continued from side
to side of the ship as an armour bulkhead. In the Achilles, Hector, and Valiant, the
armour plating is continued round the ship, but of smaller dimensions near the bow and
stern, and with corresponding smaller transverse-armour bulkheads.
The Royal Oak, Prince Consort, Caledonia, and Ocean, of 4050 tons, 800 to 1000
horse-power engines, and carrying thirty-five heavy guns, are types of the largest-sized
wood-built iron plated-ships ; the hull, with the exception of the iron upper deck and
its supporting iron beams and uprights, is entirely constructed of wood ; the exterior of
the hull to 4 feet below the water-line (in this respect similar to the iron-built ships) is
plated with 4|-inch iron entirely round.
The Enterprise, of 993 tons, is the type of the smaller-sized wood-built ship ; she is
constructed to carry four heavy guns within a square battery of 4^-inch iron, and has a
continuous armour belt of 4|-inch iron round the ship ; the upper deck, deck beams,
and top sides are of thin plate-iron.
The Royal Sovereign, of 3765 tons, is an experimental class of vessel; she was origin-
ally a wood-built three-decked ship of 110 guns, but now cut down to the lower-gun
deck, plated continuously round with 5^-inch iron, and with an iron upper deck and
bul works. The armament of five guns of large calibre is worked within four turrets ;
the iron frame of these turrets varies in thickness from 5^ to 10 inches ; and the largest,
arranged to carry two guns, weighs 146 tons.
The internal arrangements of all these classes of ships allow little room for selection
in the position of the compasses. The accurate drawings, kindly furnished by the
Department of the Controller of the Navy, enables their several positions to he shown
with reference to the most important masses of iron.
CHARACTER OE THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY.
291
TABLES OF COEFFICIENTS.
I. Iron-plated, Iron-built Ships.
II. Iron-plated, Wood-built Ships.
III. Iron-built Ships, Her Majesty’s Navy.
IV. Iron-built Ships, Mercantile Marine.
Table op Terrestrial Magnetic Elements employed in discussion
OP MAGNETIC COEFFICIENTS.
292 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
Table I. — Iron-plated, Iron-built Ships.
Compass.
Approximate coefficients.
A
B
c
D
E
51
S3
e
$
• e
1" r
p
piiec
Standard.
Greenhithe . .
Sept. 16, 17, 1861
+1 7
-24 15
- 7 42
+ 9 23
0 1
+0 39
+•019
-•449
-124
+•164
+•010
«
19,
Portsmouth. .
Oct. 15, 17, 1861
-1 0
-22 12
- 5 52
+ 8 56
+0 44
-•017
-•409
-•092
+ •155
+•013
in
19
Gibraltar ...Feb. 1862
-IS 51
— 6 0
+ 8 20
+0 23
--293
-•095
+-I45
+•006
s
■9
Portsmouth... July 28, 29, 1862
-0 12
-17 24
- 7 9
+ 8 27
+ 1 8
-•003
-•321
-•114
+•148
+•020
■Ml
19
Gibraltar ...Nov. 1862
+ 1 0
-14 39
- 4 5°
+ 8 25
-0 43
+•017
—•272
-•077
+•146
—•012
±
P
■9
f Heeled 7-J0 to Fort
+0 50
14 43
+ 6 45
+ 8 9
+° 59
+•015
-•272
+•108
+•*43
+•017
hi
If
in
Lisbon -I Upright, Jan. 1863 ...
+0 50
— H 33
- 3 34
+ 7 48
—0 24
+•015
—•269
-■057
+•136
-•007
■"
*6
P
t Heeled 7I,-0 to Starboard
+0 44
-15 36
-13 37
+ 8 17
-0 45
+•013
-•287
—•216
+-I45
-•013
* V
Devonport ...May 1, 1863
-0 12
-17 10
- 8 18
+ 8 26
-0 32
-•003
-•317
-132
+•146
-■009
r
203
Madeira Bee. 28, 30, 1863
-1 59
— 12 56
— 2 48
+ 7 15
-0 4
-'°35
-•239
— •046
+■126
—•001:
191
Plymouth ...June 1864
+0 25
-16 45
- 3 24
+ 8 44
-0 19
+■007
-•311
-•054
+152
-•005
r
190
Portland
Oct. 28, 1864
-0 17
-16 35
- 4 33
+ 8 45
-0 41
-•005
-•307
-•072
+•152
-■012
1®
193
Starboard
Greenhithe ...Sept. 16, 17, 1861
+0 20
-20 19
- 7 35
+ 15 28
-0 7
+•006
-•395
-111
+•268
-•002
f
195;
steering.
Portsmouth... Oct. 15, 17, 1861
+0 12
-20 37
- 6 37
+15 51
-0 11
+■003
-•402
-•098
+■273
-•003
Ml
193j
Portsmouth... July 28, 1862
-1 48
-15 31
- 7 50
+ 11 56
+0 43
-031
-•296
-•121
+•208
+•012
Jin
202
Devonport ...May 1, 1863
-0 7
-16 28
-10 24
+ 12 3
-0 31
-•002
-•312
-•160
+•210
-•009
js
20/
Main deck.
Greenhithe ...Sept. 11, 1861
-0 30
-25 56.
-12 6
+10 58
-1 15
1 [
Greenhithe ...Sept. 16, 17, 1861
+0 55
-22 34
- 7 49
+ 11 43
-1 46
Standard.
Greenock1 ...
Nov. 1861
+0 10
+23 0
+ 3 41
+ 8 19
+0 25
+•003
+•422
+•058
+•145
+•00;
8
Portsmouth... Sept. 2, 1862
+0 49
+20 59
+ 4 40
+ 7 38
0 0
+ 014
+•383
+•074
+•134
•00(
u
11
f Heeled to Port
+° 57
+15 31
+ 9 11
+ 6 45
+1 50
+•016
+ '282
+•148
+•117
+•035
*?{
Lisbon \ Upright, Jan. 1863 ...
—0 1
+15 39
+ 3 12
+ 7 24
— I 20
•000
+•288
+•052
+•129
— •02';
h
ioj
y Heeled 6£° to Starboard
+0 1
+ 15 14
— 2 6
+ 7 14
-I 25
•000
+•280
-•034
+•126
— •021!
353
Portland
J une and July 1863
+0 2
+21 8
+ 4 10
+ 7 6
+0 51
•000
+•384
+•067
+•124
+•011
lj»
10
Madeira
Jan. 1864
-0 25
+ 13 12
+ 4 29
+ 7 *9
—0 6
—•007
+•243
+•072
+•128
-■00
»
.0}
Lisbon
Jan. and Feb. 1864
+0 2
+ iS 8
+ 3 59
+ 7 20
—0 38
•000
+•278
+•064
+•128
— •oil,
i]
Portland Mar. and Apr. 1864
+ 1 22
+21 16
+ 5 24
+ 7 54
-0 24
+•024
+•389
+•086
+•137
-•00;
; |P
12}
Portland
Oct. 1864
+0 30
+ 19 5
+ 35
+ 7 2
-0 3
+•009
+•349
+ 050
+•122
-•00;
a j
Starboard
Portsmouth. . .
Sept. 2, 1862
+2 59
+20 9
+ 8 10
+ 10 32
+ 1 37
+ 052
+•379
+•136
+■184
+•02!
k nr
steering.
Plymouth . . .
Nov. 1864
+2 19
+ 19 40
+ 6 13
+ 8 18
+ 1 45
+•010
+ •363
+•103
+•144
+-03(
p
IS
Main deck.
Portsmouth...!
Sept. 2, 1863
— ! 9
+27 25
+ 84
+ 13 16
+0 2
-•020
+•516
+•120
+•231
•001
1-
:« |
13
Exact coefficients.
.((iisimsk
ffeilw
\0^r
Warrior.
(6109 tons),
Iron-plated,
iron hull,
40 guns,
1250 horse-power.
Built at Blackwall
River Thames ;
head N. 3° E.
magnetic.
Launched
Dec. 29, 1860.
Plated with head
generally to N.W.
Black Prince.
(6109 tons),
Iron-plated,
iron hull,
41 guns,
1250 horse-power.
Built at Glasgow ;
head S. 20’ E.
magnetic.
Launched
Feb. 27, 1861.
Plated head South.
1 X observed at Greenock =-804, multiplied by earth’s horizontal force '89='716.
“‘tatoj'oi
CHAEACTEE OF THE ABMOUB-PLATED SHIPS OF THE EOYAL NAVY. 293
Table I. — Iron-plated, Iron-built Ships.
Km
um of semicircular
deviation
V B2+C2
Coefficients of
horizontal induction.
Part of D from
Mean
Heeling
Heeling coefficients
from
9
tan 8
H(
ontal force of ship
Vi 82+S2*-
force to
North,
X
Fore-
and-aft,
Transverse
Fore-
and-aft
induction.
Transverse
Vertical
force,
f*
t
coefficient
to
windward ,
Vertical
induction
Vertical
force and
9
i
mnt.
Direction.
a
t
e
t
induction.
X
in trans-
verse iron.
induction
in vertical
t
t
o
O
0 1
0 1
° 1
0 1
•466
1954
23 |
16
4
154
•419
(■308
\-409
•341
r-z8z
{■375
1924
198
1994
196
•873
1-145
+•002
-•256
+0 6
+ 8 24
1-399
+1 49
+0 43
+ 1 06
1
+
+•069
15 ;j
'293
(■* 75
\-345
r584
192
+ 1 22
+0 32
+0 50
•360
217
19
•344
203
■860
1163
-•015
-•265
-0 28
+ 8 52
1 4
17
[■243
\ -328
•314
r9i
190
174
•316
193
214
•410
1954
21f
•414
1934
17|
•320
202
•833
1-201
+•006
-•340
+0 14
+ 11 46
194
•352
207
•878
M39
+•062
-•306
+2 0
+10 04
234
■426
8
/•804
1-716
1-396
-180
-•388
-7 15
+ 15 40
204!
■390
11
•783
1-277
-112
-•322
-4 4
+11 42
•945
+0 50
+1 1
-0 11
+ •048
+ 118
16
•318
(•293
\-369
•282
274
104
353
+0 52
+° 43
+ 09
204!
■390
10
H
/■254
t‘343
164
i5l
1-286
1 -360
»3
778
1-285
— •122
-•322
-4 28
+ 11 53
22
•399
I24
•846
M82
-•038
-•270
-1 19
+ 9 11
•971
+0 43
+0 48
-0 5
+•045
194
•354
8
■849
1-178
-•047
- 255
-1 36
+ 8 38
21?
•404
20
■760
1-316
-•100
-•380
-3 47
+ 14 28
204
j -377
16
•881
1135
+•008
-•246
+0 14
+ 8 4
284
•530
13
•757
1-321
-•068
-•418
-2 35
+ 15 58
ian force to North (XH) being unit. f Earth’s Horizontal force (H) being unit. % Earth’s Vertical force (Z) being unit.
294
STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
Table I. (continued). — Iron-plated, Iron-built Ships.
Approximate coefficients.
Exact coefficients.
l
l
Compass.
Place.
Date.
i
A
B
c
D
E
21
23
<E
£>
g :
O f
0 1
0 1
O /
0 1
Standard(aft).
Sheerness . .
Oct. 12, 13, 1864
-0 16
+19 54
+ 2 56
+ 6 58
-0 56
-•005
+•362
+ 047
+ 121
-•01
Plymouth t ..
Dec. 5, 1864
-0 35
+19 54
+ 7 38
+ 6 41
-0 32
-010
+•361
+■123
+•116
-•00
Standard
Sheerness ...Oct. 12, 13, 1864
-0 10
+21 42
+ 1 11
+ 7 19
-0 31
-■003
+•396
+ 019
+•128
-■00
(forward).
Plymouth . .
Dec. 5, 1864
+0 39
+ 19 51
+ 6 15
+ 5 44
-1 01
+•011
+•357
+•102
+ 100
-4
Starboard
Sheerness . .
Oct. 12, 13, 1864
+0 07
+23 31
+ 4 10
+ 8 51
-1 20
+•002
+•432
+ 061
+•154
-02
steering.
Plymouth . .
Dec. 5, 1864
-0 55
+23 30
+ 10 04
+ 7 51
-0 30
-016
+•427
+•160
+ 137
-00
Main deck
Sheerness . .
Oct. 12, 13, 1864
-0 47
+12 42
+ 2 19
+12 13
+0 21
-014
+•244
+•031
+•214
+•00
(starboard).
Plymouth . .
Dec. 5, 1864
-1 11
+14 17
+ 3 49
+10 46
+1 23
-•021
+•271
+•059
+ 188
+•02
-
Standard.
Sheerness ...Feb. 17, 18, 1862
-0 28
+25 43
+ 0 17
+ 7 0
+0 5
-•008
+•464
+ 005
+•122
+-001
Baltic Sea ...July and Aug. 1862
-0 17
+2 * * S.5 35
- 0 25
+ 6 25
—0 41
—•005
+•463
— •007
+•112
—•01
Gibraltar . .
.Nov. 15, 1862
+0 16
+ 15 21
- 4 15
+ 69
+0 25
+•005
+■280
—•069
+•107
+'°°! !
f Heeled to Port
+ 1 47
+ 16 39
+ 2 49
+ 7 18
+1 50
+•031
+'3°5
+•045
+•127
+•03 ,
Lisbon < Upright, Jan. 1863 ...
+ 1 41
+ 16 26
- 1 5
+ 74
+0 42
+•029
+•302
— ■018
+-i*3
+‘°1 ■'
(_ Heeled 7J6 to Starboard
+ 1 38
+ 16 27
- 4 40
+ 70
-0 5
+■028
+-3°i
-•075
+•122
+■0(1 li
Flushing &1
Portsmouth J
March 3, 21, 1863
+0 5
+20 50
- 2 8
+ 6 50
-0 11
+•001
+•379
-•034
+ 119
-Oflj
Plymouth . . ,
Tenerife
.Dec. 1863
+ 1 6
+22 18
- 0 57
+ 6 59
-0 7
+•019
+■403
+ •292
-016
+ 122
+•114
-•00.;
.Jan. 2, 3, 1864 ...
—•040
Gibraltar . .
.Jan. 9, 13, 1864...
— 1 0
+ 15 25
- 1 44
+ 6 30
—0 46
-•017
+•282
— ■928
+ ■113
—•oil
Lisbon
.Jan. and Feb. 1864
+0 40
+ 16 37
- 1 18
+ 6 22
-0 7
+ •012
+ ‘3°3
— •021
+■111
— -oc
Portland
.Mar. and Apr. 1 864
+0 21
+21 37
- 0 24
+ 6 26
-0 24
+•005
+ •391
-•007
+ 112
— oc ;
Portland
Oct 1864
-0 23
+20 55
-26
+ 6 23
+0 10
-007
+■379
-034
+•112
+’0(
Starboard
Sheerness . .
.Feb. 17, 18, 1862
+0 16
+ 36 14
+ 0 56
+10 16
+ 1 7
+•005
+•653
+•014
+•179
+ 011
steering.
Plymouth . .
Portland & 1
Downs ... J
Dec. 1863
+1 4
+31 18
- 1 21
+ 10 19
+0 36
+•019
+•572
-•020
+ 180
+•01
Apr. and May 1864
+ 014
+•586
-•030
+•159
+01
Devonport ..
.Nov. 1864
+•546
-056
+ 159
...
Main deck.
Sheerness . .
.Feb. 17, 18, 1862
-0 51
+36 23
+ 0 42
+ 14 35
-0 55
-•015
+ •669
+•010
+•254
-0,|
Plymouth . .
Portland &1
Downs ... J
.Dec. 1863
+ 1 16
+26 44
+ 0 34
+ 13 10
-0 6
+ 022
+•505
+•009
+•230
-•oc;
Apr. and May, 1863
+ 019
+•450
+•004
+•233
-•01
Devonport ..
Nov 1864
+•486
-030
+•230
J
Achilles*.
(6121 tons).
Iron-cased,
iron hull,
20 guns,
1250 horse-power.
Built at Chatham,
and fully plated
in dock ; head
S. 51° 40' E.
magnetic.
Floated outofdock
Dec. 24, 1863.
Defence.
(3720 tons).
Iron-plated,
iron hull,
16 guns,
600 horse-power.
Built on River
Tyne ; head
S. 47° W. magnetic
Launched
Apr. 24, 1861.
Plated with head
S. 19° E. magnetic.
S3
•464
* A ™tt fa tw o<? 1 QRQ f In dock at Chatham ; by observations of deviation and horizontal force on one point, and
’ ( employing X and 3) of Oct. 1864 (no machinery on board, or internal fittings) j
SeDt 26 1864 I Complete in equipment ; by observations of deviation and horizontal force on one point. 1 _ _|_ .377
" ' ’ ( Head moored N. 62° W., same X and 3) as above I
Oct. 11, 1864. Same observations, X and 35 as above. Head moored S. 54° 40' E
t After having remained in dry dock 25 days. Head S. 79° E. magnetic.
S
+•323
. — + -355
+ •037
+•062
CHARACTER OE THE ARMOUR-PLATED SHIPS OF THE ROYAL NAYY. 295
Table I. (continued). — Iron-plated, Iron-built Ships.
Mai
im of semicircular
defiatiou
Coefficients of
horizontal induction.
Part of D from
Heeling coefficients
from
VB2 + C2
Mean
Mean
Heeling
Ho
ntai lorce of ship
Vertical
coefficient
g
V5B2+£2*
Fore-
force,
f6
to
V ertical
Vertical
and-aft. Fransverse
Transverse
windward,
induction
force and
tan 0
9
A
uut.
Direction.
t
a
t
e
t
and-aft
induction.
induction.
X
in trans-
verse iron.
induction
in vertical
iron.
t
t
0
O
0 f
° 1
0 !
0 1
0 1
20*
•365
7 i
•8 22
1-216
-•079
-•277
-2 45
+ 9 40
•870
+0 27
+0 50
-0 23
+■079
+■194
21
•381
18*
•854
1171
-•047
-■245
-1 36
+ 8 17
•896
+0 25
+0 43
-0 18
+ •084
+ •210
21|
•397
2*
■831
1-202
-063
-•275
-2 7
+ 9 30
1-217
+ 1 29
+0 49
+0 40
-070
+ •172
20|i
•371
16
■872
1-147
-•041
-•215
-1 22
+ 7 7
1-240
+ 1 18
+0 37
+0 41
-066
+ •165
24
•437
8
•777
1-287
-•103
-•343
-3 47
+ 12 43
25*
•458
20*
•819
1-221
-069
-•293
-2 24
+ 10 15
13
•246
7*
•755
1-325
-•083
-•407
-3 9
+ 15 36
m
•278
12*
•804
1-244
-•045
-■347
-1 36
+ 12 28
25i
•464
360*
•822
1-217
-•078
-•278
-2 42
+ 9 44
1-040
+0 59
+0 51
+0 8
+•056
+•138
iSij
{■463
\ -440
359f
16 1
J-288
346
1-383
■317
»5*"l
1 6*1
J '3°3
.t'381
356*
+0 30
+0 33
CO
0
17 f
•311
346 J
21
•391
355
22* 1
•403
358
•853
1172
-•043
-•251
-1 26
+ 8 28
J ’z94
1 -408
352
■846
1-182
— •058
-■250
-1 57
+ 8 31
"51
r-z83
1 -376
354
■853
ri72
-•051
-•243
— 1 40
+ 8 13
16*
J '3°4
\-382
356
•827
1-209
— •081
-•265
-2 49
+ 9 16
21*
•392
359
■857
1-167
-•071
-•263
-1 33
+ 80
•968
+0 36
+0 42
-0 6
+•064
+ 157
21
•381
355
•852
1 174
-•053
-•243
-1 46
+ 8 13
36*
•654
361*
•794
1-258
-064
-•348
-2 17
+ 12 35
31*
•572
358
•842
1-118
-006
-•310
-0 14
+ 10 36
•586
357
•853
1-172
-036
-•308
-0 21
+ 9 33
•558
348*
•830
36*
•669
361
•759
1-318
-•048
-•434
-2 10
+ 16 58
26f
•505
361
•810
1-235
-004
-•376
-0 8
+ 13 24
•450
360*
•828
1-208
+■021
-•365
+0 41
+ 12 42
•487
356*
•842
M88
+ 036
-•352
+ 1 12
+ 12 4
* 1 in force to North (XH) being unit. t Earth’s Horizontal force (H) being unit. | Earth’s Vertical force (Z) being unit.
MDCCCLXV.
9
296 STAFF COMMANDER EVANS AND ME. A. SMITH ON THE MAGNETIC
Table I. (continued). — Iron-plated, Iron-built Ships.
Ship.
Compass.
Place.
Date.
Approximate coefficients.
Exact coefficients.
Eiofwmicirt
iflEtiOB
iw L
iblfwetf*
A
B
C
D
E
51
£
$
e
aw
It
Resistance.
! (3710 tons),
| Iron-plated,
iron hull,
1 6 guns,
[ 600 horse-power.
Built at Millwall,
River Thames ;
head S. 86V W.
magnetic.
Launched
April 11, 1861.
Plated with head
generally to West-
ward.
Standard.
Sheerness Aug. 25, 26, 1862. . .
Lisbon Jan. 1863
Portsmouth... June 19, 1863
Portsmouth... Dec. 1863
Malta Jan. 1864
Malta Dec. 27, 1864
+0 36
+ 1 54
+0 44
+1 1
-0 19
-0 4
+ 89
+ 45
+ 8 21
+ 5 46
+ 1 36
+ 2 30
- 9 41
- 6 27
- 8 24
- 7 22
- 6 13
- 6 43
0 1
+ 6 17
+ 6 54
+ 5 48
+ 70
+ 6 45
+ 5 58
0 !
+0 8
+° 59
-0 54
-1 59
— I 20
+■010
+'°33
+•013
+ •018
— 'OO5
— *00 1
+•149
+'°75
+ 152
+•106
+•030
+•<344
-•158
-•105
-•138
-•120
— •102
— -n6
+•111
+•120
+ 101
+ 122
+•117
+•104
+-01C
+'0I'i
-•oie
-■034
— *02Cj
§
:p
!•;
r
■i
h
1
fir
§
-
Starboard
steering.
Sheerness Aug. 25, 26, 1862. . .
Portsmouth... June 19, 1863
Portsmouth... Dec. 1863
+0 24
+ 1 20
+2 10
+ 7 55
+10 41
+ 9 42
-17 15
-13 23
-12 25
+ 8 28
+ 8 56
+ 9 43
+ 1 9
-0 51
-0 49
+ ■007
+•023
+ •038
+ •147
+■198
+•181
1 — -274
-•212
-•196
+ •148
+•155
+•170
+-02(
— 017
—014
Main deck.
Sheerness Aug. 25, 26, 1862. . .
Portsmouth... June 19, 1863
Portsmouth... Dec. 1863
-0 18
+2 9
+3 5
+ 9 24
+ 96
+ 3 41
-17 9
-13 6
-11 11
+ 14 0
+ 13 25
+ 12 39
+0 21
+ 1 12
-3 30
-•005
+•020
+•054
+■181
+ •175
+•070
-•260
—200
-•173
+■244
+•232
+•219
+-00f
+■021,
-■061;
Sr
«
f
Hector (1).
(4089 tons),
Iron-cased,
iron hull,
28 guns, 800 h.-p.
Built at Glasgow ;
head S. 20° E.
magnetic.
Launched
Sept. 26, 1862.
Plated with head
N. 55° W. and
S. 49° W.
Standard.
Portsmouth... Eeb. 16, 1864
-0 24
+21 53
+ 4 54
+ 5 24
-0 39
-•007
+■392
+•079
+•094
—on
if
f
]
1
Starboard
steering.
Portsmouth... Eeb. 16, 1864
+0 37
+30 36
+ 10 37
+ 8 24
-0 16
+ 011
+•545
+-164
+ 147
f
—•007
Main deck.
Portsmouth... Feb. 16, 1864
+0 16
+31 22
+ 13 50
+ 9 47
-0 50
+•004
+•520
+■239
+•170
—01
Valiant.
(4144 tons),
Iron-plated,
iron hull,
28 guns, 800 h.-p.
Built at Millwall,
River Thames ;
head S. 87° W.
Launched
Oct. 14, 1863.
Plated with head
generally to West-
ward.
Standard.
Sheerness ...Jan. 12, 16, 1865...
+ 1 2
-f- 2 30
-12 44
+ 4 54
-0 43
-*-•018
+•046
-•211
+•085
-•01:
is 25*>
ij 1 »S3
Starboard
steering.
Sheerness ...Jan. 12, 16, 1865...
+2 7
+ 7 35
-20 12
+ 6 52
-0 14
+•037 ■
+•138
-•325
+•120
-•00
—
Main deck
(Starboard).
Sheerness ...Jan. 12, 16, 1865...
+2 35
+ 5 29
-18 39
+ 85
-0 12
+■045
+•101
-•297
+•142
—00
11
2®
(l) Hector, June 9, 1863. In basin at Portsmouth, by observations of Deviation and Horizontal force on one point, and employing X and D of
February 1864, B= + -398, C = + '159.
CHAEACTEE OE THE AEM OTJE-PL ATED SHIPS OP THE EOTAL NAVY. 297
Table I. (continued). — Iron-plated, Iron-built Ships.
a
Mas
um of semicircular
deviation
V B2+C2
Mean
Coefficients of
horizontal induction.
Part of D from
Mean
Vertical
force,
P
Heeling
coefficient
Heeling coefficients
from
Ho
mtal force of ship
/W+W2*.
North,
X
X
Fore-
and-aft,
Transverse
Fore-
Transverse
windward,
X
Vertical
induction
Vertical
force and
g
tan0
9
unt.
Direction.
t
t
t
induction.
induction.
t
in vertical
iron.
t
t
~ "1
o
° /
0 /
0 1
° /
0 !
12*|
•218
313
•758
1-319
-•158
-•326
-5 55
+12 21
1071
+1 18
+1 4
+0 14
+•071
+•176
r-i29
1-162
3°5*
m
•205
317f
9*
•160
311*
•850
1-176
-046
-•254
-1 33
+8 34
1044
+0 53
+0 45
+0 8
+•076
+•190
6*
/’JO 7
\ -158
285*
7*
/•124
I-J83
291
19
•312
298
■703
1-423
-•193
-•401
-7 53
+ 16 33
m
•290
313
151
•266
313
19*
•316
305
•782
1-279
-•027
-•409
-1 2
+ 15 11
16
•266
311
114
•187
292
•880
1-136
+■073
-■313
+2 25
+10 15
24*
•400
12*
•814
1-228
-■109
-•263
-3 51
+ 9 15
•983
+0 45
+0 48
-0 3
-•005
-•013
33*
•568
16*
•791
1-264
-•093
-•325
-3 23
+ 11 49
34*
•572
25
•726
1-377
-151
—397
-5 58
+15 54
13
•216
282*
•859
M64
-•068
-•214
-2 14
+ 7 11
1-061
+0 48
+0 37
+0 11
+•048
+•120
21*
•353
293
•817
1-224
-•085
-•281
-2 59
+ 9 54
19*
•313
288*
•722
1-385
-•176
-•380
-6 56
+15 14
ean force to North (\H) being unit. f Earth’s Horizontal force (H) being unit. + Earth’s Vertical force (Z) being unit.
2 s 2
298
STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
Table II. — Iron-plated, Wood-built Ships.
Ship.
Compass.
Place.
Date.
Approximate coefficients.
Exact coefficients.
A
B
1 \°
D
E
21
25
(£
©
a
Royal Oak.
Iron-cased,
wood-built,
4056 tons, 35 guns,
800 horse-power.
Iron-plated ;
head S. 49° E.
Floated out of dock
March 19, 1863.
Standard.
Chatham Mar. 19, 1863
Chatham Apr. 11, 1863
Sheerness June 2, 1 863
Plymouth ...Jan. 8, 1864
Malta Mar. i, 1864
0 1
-0 39
-0 12
-1 9
+13 56
+ 12 20
+ 88
+ 7 26
+ 10 9
+ 6 1
+ 39
+ 2 19
+ 2 58
° 1
+0 1
+0 20
— 0 48
-011
-•003
— '020
+•253
+ •231
+•248
+•218
+'H3
+ ■287
+ 197
+•128
+•172
+ *I08
+•047
+ •061
+ •055
+•040
+•052
2
•00
+-0uij
— *0 1.j
Starboard
steering.
Chatham Apr. 11, 1863
Sheerness June 2, 1863
+0 15
+24 5
+ 14 25
+ 1 47
+ 1 17
+•004
+•377
+•414
+•379
+ •241
+ 067
+ 031
+•02:
Main deck.
"Sheemess J une 2, 1863
-1 54
+32 22
+ 12 47
+ 1 28
-0 11
-•033
+•546
+■210
+ ■026
—•00:
Prince Consort.
Iron-eased,
wood-built,
4045 tons, 35 guns,
1 000 horse-power.
Iron-plated ;
j heads. 39° W.
Standard.
Milford May 25, 1863
Plymouth ...Feb. 9, 1864
-0 6
-0 28
+33 39
+25 36
-13 41
- 3 53
+ 2 18
+ 36
-0 4
-0 33
-001
-008
+ •569
+•447
-•222
-•064
+ 040
+•054
-00
-•01
Caledonia.
Iron-cased,
wood-built,
4125 tons, 35 guns.
1000 horse-power.
Iron-plated ;
headS. 26° W.
Standard.
Sheerness June 15, 1864
+0 18
+25 47
- 8 21
+ 2-57
+0 20
+ •005
+■448
-•138
+•051
;
+-00i
Ocean.
Iron-cased,
wood-built,
4047 tons, 35 guns.
1000 horse-power.
Iron-plated ;
head S. 79° E.
Standard.
Devonport ...Aug. 3, 1864
+0 8
+13 2
+ 15 23
+ 2 31
-0 4
+ •002
+ •229
+■259
+•044
— 00
Royal Sovereign.
Iron-cased,
wood-built,
turret ship of
1 5 guns, 3765 tons,
800 horse-power.
Iron-plated ;
head S. 72° E.
1
Standard.
Portsmouth... July 21, 22, 1864
-0 3
+ 12 38
+ 13 39
+ 7 41
+0 7
-•001
+•233
+ •219
+•134
+■00
Steering wheel
(upper deck).
Portsmouth. . .July 21, 22, 1864
-1 8
+23 30
-19 40
+ 13 3
-9 14
-022
+•487
-•323
+•238
-•15l
Steering wheel
(Cap.’s cabin).
Portsmouth... July 21, 22, 1864
-0 25
+20 11
+ 4 56
+ 6 20
-5 10
-•007
+•364
+•086
+ 110
-•09
Starbaforward
(lower deck).
Portsmouth... July 21, 22, 1864
-0 37
-13 15
+40 15
+ 15 43
-4 42
-•004
-•277
+ ■563
+•272
-07
Port, forward
(lower deck).
Portsmouth... July 21, 22, 1864
+6 42
-14 35
-78
+ 13 23
+4 38
+•117
-•286
-•119
+ ■233
+-08i
+•01
Suspended
over fore-
turret.
Portsmouth. . .July 21, 22, 1864
+1 0
-19 33
+ 9 23
+ 89
+ 0 1
Enterprise \
(993 tons), 4 guns,
160 h.-p. screw.
Built and plated at
Deptford; head
S.56°W. Launched
February 1864.
Standard.
Greenhithe ...June 7, 1864
+ 1 24
+14 42
-18 45
+ 2 34
+0 35
+•025
+•257
-•312
+•045 ■
Wolverene 2.
(703 tons), 2 1 guns,
400 h. p. screw.
Built at Woolwich;
head S.S.W.
Launched in 1863.
Standard.
Greenhithe ...May 31, 1864
+0 23
+ 14 10
- 2 11
+ 3 20
+0 46
+•007
+•253
-•036 ■
+•058 ■
+01
1 Wood bottom, Iron-cased, with central iron battery. Iron topsides, decks and beams. a Wood hull, iron beams and stanchions.
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL KAVY.
299
Table II. — Iron-plated, Wood-built Ships.
Maa
um of semicircular
deTiation
Coefficients of
horizontal induction.
Part of D from
Heeling coefficients
from
VB2+C2
Mean
Mean
Heeling
Ho
jntal toree ot ship
Vi82+S'2*
force to
North,
X
Fore-
and-aft,
Transverse
Fore-
and-aft
induction.
Transverse
Vertical
force.
t
coefficient
windward,
Vertical
induction
Vertical
force and
J7_
tan 0
9
A
unt.
Direction.
t
a
+
t
induction.
X
in trans-
verse iron.
induction
in vertical
iron.
t
t
0
•382
48|
•861
1-162
-•098
-•178
° \
-3 16
+ 62
° 1
° i
° 1
1
■304
40*
•907
1102
-038
-•148
-1 12
+ 4 39
•896
+0 7
+0 24
-0 17
+■018
+ 045
51
•280
27*
•907
1-102
-043
-143
-1 19
+ 4 32
•882
+0 4
+0 23
-0 19
+■052
+•127
6
0
•278
S'I79
[-264
38
37
•534
45
•887
1127
-054
- 172
-1 43
+ 5 30
8
•480
30
•906
1104
-•066
-•122
-2 7
+ 3 51
If
•586
21
•862
1160
-•116
-160
-3 51
+ 5 20
J
•612
339
•840
1190
-•126
-•194
-4 18
+ 6 36
6
■452
352
•950
1053
+ •001
-101
0 0
+ 36
•848
-0 8
+0 16
-0 24
+•015
+•038
!7
•469
343
•895
1117
-059
-•151
-1 53
+ 4 46
•346
48*
•923
1083
-■036
-118
-1 9
+ 3 40
•929
-0 15
+0 19
-0 34
+ 045
+•112
18*
•320
43*
■912
1-097
+ •044
-•204
+ 1 5
+ 6 36
50*
■584
326
•980
1020
+•202
-■212
+5 58
+ 7 7
■374
13*
•917
1091
+•028
-•184
+0 34
+ 5 45
Ml?
•629
116
•783
1277
-•003
-•431
-0 2
+ 15 55
16*
■310
203
■811
1-233
■000
-■379
0 0
+ 13 25
23f
•406
309*
•817
1-224
-146
+■220
-5 6
+ 7 44
•622
-0 29
+0 37
-1 9
+•062
+•152
•256
352
•962
1039
+ 018
-094
+0 35
+ 2 45
•953
+ 0 7
+0 14
-0 7
L
#
M
a
force to North (\H) being unit.
t Earth’s Horizontal force (H) being unit.
J Earth’s Vertical force (Z) being unit.
300 STAFF COMMANDEE EVANS AND ME, A. SMITH ON THE MAGNETIC
Table III. — Iron-built Ships, Her Majesty’s Navy.
deviation
lib! I®*1
Ship.
Compass.
Place.
Date.
Approximate coefficients.
Exact coefficients.
A
B
C
D
E
2t
S3
e
lit
Orontes.
(2812 tons),
4 guns, 500 h.-p., screw.
Built at Birkenhead ;
head N. 66° W. magnetic.
Launched Nov. 22, 1862.
Standard.
Plymouth ...May 26, 1863
Portsmouth ...July 7, 1863
G.ofGoodHope, Nov. 1864
-0 31
-0 2
-1 40
0 1
- 7 45
- 6 55
“ 9 39
0 !
-12 20
-12 0
— 10 41
+5 46
+5 30
+5 49
0 1
-0 24
-0 13
0 0
-009
•000
— •029
-141
-•125
-•177
-•203
-•198
-•178
+•100
+•096
+•101
-•007
-•004
•ooc
U
•234
F
p
Starboard
steering.
Portsmouth ...July 7, 1863
-0 43
-10 27
-13 7
+7 16
-0 22
-•012
-•191
-■213
+•126
— 00(
u
Tamar.
(2812 tons),
4 guns, 500 h.-p., screw.
Built at Millwall, River
Thames ; head West.
Launched Jan. 5, 1863.
Standard.
Sheerness Nov. 21, 23, 1863
Portsmouth ...Oct. 1864
+0 18
+0 4
+ 1 42
+ 2 11
-10 49
- 5 26
+3 18
+3 11
+0 33
+0 22
+•005
+•001
+■031
+•038
-•184
-•095
+■058
+•056
+■011
+ 001
f
■»
Starboard
steering.
Sheerness Nov. 21, 23, 1863
-1 50
+ 7 15
-17 14
+3 27
+0 8
-•032
+•128
-•288
+•060
+-ooJ
■SIS
Adventure.
(1794 tons),
400 horse-power, screw.
Built at Birkenhead.
Launched Feb. 17, 1855.
Standard.
Greenhithe . . .April 26, 1 862 . . .
Greenhithe ...Oct. 28, 1862 .. .
Yokohama, Japan. . .Nov. 1 1 , 1 864.
+0 2
+0 8
- 4 5
- 3 59
- 3 28
+ 10 59
+ 10 59
+ 8 4
+2 56
+2 53
+2 49
+0 26
+0 10
—0 19
■000
+•002
-073
-•071
— •061
+•186
+■186
+-I39
+ 051
+•050
+ ‘°49
+-00'|
+•00
i*
-B
1*
Dromedary.
(647 tons),
100 horse-power, screw.
Standard.
Greenhithe ...July 8, 1862
Greenhithe .. .Dec. 16, 1862
-f"V 32
+0 21
+ 50
+ 4 59
-11 50
-10 55
+6 0
+5 33
+0 14
+0 44
+■009
+•006
+■091
+•091
-•194
-•179
+•104
+■097
+•041
+•01;
L
#
Wye.
(700 tons),
100 horse-power, screw.
Standard.
Greenhithe ...Sept. 1, 1863
+0 25
+ 3 24
+10 50
+ 1 31
+0 5
+•007
+•059
+•186
+•026
+•00
H
Caradoc.
(676 tons),
Paddle-wheel, 350 h.-p.
Built at Blackwall.
Launched July 1847.
Standard.
Greenhithe ...Feb. 12, 1863
-0 43
-13 28
- 2 54
+2 3
-0 7
-•012
-■238
-049
+•036
—•00
!ffl ;
*1
1
Industry.
(638 tons),
Screw, 80 horse-power.
Built at Blackwall.
Launched 1854.
Standard.
Greenhithe ..March 14, 1863 ...
-0 13
+ 11 32
- 2 16
+2 58
-0 6
-•004
+•206
-•038
+•052
-■00
Supply.
(638 tons),
Screw, 80 horse-power.
Built at Blackwall.
Launched June 1854.
Standard.
Greenhithe ...Oct. 17, 1863
-0 12
-13 32
- 1 40
+2 55
+0 16
-•003
-•240
-•028
+ ■051
+•00
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 301
Table III. — Iron-built Ships, Her Majesty’s Navy.
Mai
um of semicircular
deviation
VB2+C2
Mean
Coefficients of
horizontal induction.
Part of D from
Mean
Heeling
Heeling coefficients
from
Ho
>ntal force of ship
$%*+<§?*.
North,
A
A
Fore-
and-aft,
Transverse
Fore-
Transverse
Vertical
force,
(*
coefficient
to
windward
Vertical
1 induction
Vertical
force and
9
tune
9
A
unt.
Direction.
t
t
t
induction.
induction.
*
verse iron.
in vertical
t
t
„
o
° /
o ,
° 1
0 /
° 1
14*
•247
235
14
•234
238
•875
1-143
-041
-•209
-1 22
+6 40
1-164
+ 1 4
+0 36
+0 28
+ 023
+•056
i4*
r-a5i
\-293
2Z5
17
•286
228
•862
1-160
-•029
-•247
-0 58
+8 13
11
•187
279|
•870
1-150
-•080
-•180
-2 38
+5 58
1-317
+0 51
+0 31
+0 20
+•060
+•147
6
•102
292
18 J
•315
294
•886
1-129
-■061
-•167
-2 0
+5 27
1-248
+ 1 10
+0 28
+0 42
+•120
+•294
U|
■200
111
•922
1-085
-031
-•125
-1 0
+3 56
H|
•199
111
■918
1-090
-•035
-•129
-1 8
+4 1
9
r-i5i
V249
-II3
12f]
•215
295
■841
M86
-•072
-•246
-2 21
+8 21
12
•201
297
•861
1-161
-•056
— •222
-1 50
+7 28
ll*j
•395
72
•869
1151
-•108
-154
-3 34
+
Ox
1195
+ 1 0
+0 27
+0 34
+•103
+•252
13f
•243
191*
•945
1058
- 021
-•089
-0 38
+2 42
1 002
+0 15
+0 14
+0 1
HI
•209
3491
•937
1-067
-014
-112
-0 41
+3 40
•859
-0 5
+0 18
-0 23
13|
•242
186£
•925
1-081
-•028
-•122
-0 55
+3 47
* M
1 force to North (\H) being unit.
f Earth’s Horizontal force (H) being unit.
Earth’s Vertical force (Z) being unit.
302 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
Table IV. — Iron-built Ships, Mercantile Marine.
Ship.
Compass.
Place.
Date
Approximate coefficients.
Exact coefficients.
A
B
C
D
E
%
35
e
m
@ '
° 1
o /
° I
° /
° t
Rainbow1
Station No. 1
Deptford
July and Aug. 1 838
+0 40
— 50 36
-11 4
+ 1 23
+0 38
+ 012
-•802
-•173
+•024
+•01
„ No. 2
+0 3o
-18 45
-12 57
+2 30
+0 2
+•010
-•327
-•217
+•044
+•00
„ No. 3
+0 42
-15 46
-10 39
+3 7
-0 2
+ 012
-•279
-•181
+•054
-•00,
„ No. 4
+0 5
- 8 5
- 9 33
+3 26
+0 2
+•001
— •145
-•161
+•060
■
+ •00
1
Ironsides2 . . .
Binnacle, or
Liverpool ...
Oct 27, 1838 . .
0 0
-24 16
+20 50
+2 15
— 0 1
•000
-•416
+•346
+•039
■00
i
steering.
l
Great Eastern3
Standard
River Thames... Sept. 7, 1859 ...
-0 10
+23 13
+25 38
+4 21
-0 37
-•003
+ •402
+•408
+■076
-•01
position.
Portland
....Sept. 12, 1859...
-1 3
+22 42
+ 16 43
+4 44
-0 45
-•018
+•400
+•27 2
+•082
-•01
Compass aft
River Thames... Sept. 7, 8, 1859
-l 40
+13 34
+22 41
+7 55
-0 12
-•029
+•247
+•359
+•138
-•00
on platform.
Compass on
River Thames... Sept. 8, 1859 ...
+0 3
+31 56
+ 17 47
+4 31
-0 9
+•001
+•551
+•282
+•079
-•00
fore bridge.
•
Clyde
Standard
(rrcenhithe ...T?eh. 21. 1863
+0 41
- 7 56
+ 7 25
+4 43
+0 8
+•012
-143
+•124
+ •082
•
+•00
position.
City op Sydney. . .
Standard
Greenhithe ...
.June 13, 1863
+ 1 27
- 3 29
-18 51
+4 32
+0 23
+•025
-063
-•311
+•079
+•00
position.
^(00“
feriton
IPL-r
fT'
« | 19
C j 21
I* I 21
ill I 14
I ill | 45
34
■® ! 55]
a 1 2?
« 258
ft. in. ft. in.
1 Station No. 1, (near the binnacle) 13 2 distant from the extreme part of stern, 4 0,)- from deck.
,, 2, 31 9
,, 3, 48 3
4 f 151 6 \ „
” ’ { 47 0 from knight head of stem J „ „
2 See Philosophical Transactions, 1839, Part I. p. 206.
3 See Philosophical Transactions, 1860, Part II. p. 375.
See Philosophical Transactions,
1839, Part I. p. 167.
ctetoXortl
Table of Terrestrial Magnetic Elements. [1864.]
Place.
In British absolute units.
Dip 6.
Tan i.
Horizontal force at Greenwich
being unit*.
Horizontal force.
Vertical force.
Horizontal force.
Vertical force.
Greenwich
3-83
+ 9-53
+ 68 7
+ 2*49
1-00
+ 2-49
Greenhithe
3-84
+ 9*50
+ 68 5
+ 2*48
1-00
+ 2-48
Sheerness
3*83
+ 9*50
+ 68 2
+ 2-48
1-00
+ 2-48
Portsmouth
3-86
+ 9*48
+ 67 50
+ 2*45
1-01
+ 2-47
Portland
3-88
+ 9-50
+ 67 45
+ 2-44
1-01
+ 2-47
Plymouth
3-86
+ 9-54
+ 67 58
+ 2-47
1*01
+ 2*49
Milford
3-62
+ 9-80
+ 69 44
+ 2-71
•95
+ 2-56
Greenock
3-38
+ 10-04
+ 71 23
+ 2-97
•88
+ 2-63
For British absolute units multiply by 3-83.
For Foreign absolute units multiply by 1-76.
11
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY.
303
Table IV. — Iron-built Ships, Mercantile Marine.
Alaxi
m of semicircular
deviation
V B*+C»
Mean
force to
North,
X
t
X
Coefficients of
horizontal induction.
I Part of D from
Mean
vertical
force,
Heeling
coefficient.
windward ,
*
Heeling coefficients
from
9
tan 0
9
t
Hori
ital force of ship
!&+&*■
Fore-
and-aft
a
t
Transvers<
e
t
Fore-
and-aft
induction.
Transverse
^induction.
Vertical
induction
in trans-
verse iron
Vertical
force and
induction
in vertical
Am
*
Direction.
-
o
° i
° 1
° i
o /
•822
192
•984
1016
+•008
-■040
+0 14
+ 1 9
2J
•392
213
•972
1029
+•015
-071
+0 24
+2 7
•332
213
i 1-003
•997
+•057
-•050
+1 40
+ 1 26
•217
228
•999
1001
+•060
-•060
+ 1 43
+ 1 43
2
■542
140
•914
1-094
-•050
-•122
-1 33
+3 50
. -574
45iV
•791
1-264
-•072
-192
-3 50
+8 13
;-4S4
34£
•775
1-291
-•082
-•209
-4 4
+8 48
H [i
•438
55 £
•897
1115
+•066
-•182
+0 38
+7 18
H 1
•619
27
•892
1121
-•038
-•178
-4 38
+9 16
1
•189
139
■870
1149
-•059
-•201
-1 57
+6 39
1 1-275
1 22
+0 35
+0 47
l
H
•158
258J
•816
1-225
-•120
-■248
-4 8
+8 44
1-246
1 31
+0 46
+0 45
* Me
force to North (\H) being unit.
f Earth’s Horizontal force (H) being unit.
X Earth’s Vertical force (Z) being unit.
Table of Terrestrial Magnetic Elements. [1864.]
Place.
In British absolute units.
Dip 6.
Tan 6.
Horizontal force at Greenwich
being unit || .
Horizontal force.
Vertical force.
Horizontal force.
1 Vertical force.
Lisbon
4-82
+ 8-46
+ 7*89
+ 8-27
+ 8-10
+ 7*29
-6-43
+ 7-08
+ 60 23
+ 1-76
+ 1-55
+ 1-60
+ 1-49
+ 1-29
-1-44
+ 1*12
1-26
+ 2-21
Gibraltar
5-09
5-17
5*44
+ 57 9
+ 57 55
+ 56 10
+ 52 20
1 — 55 8
+ 48 10
1-33
+ 2-06
Madeira
1-35
+ 2-16
+ 2-12
Teneriffe
1*42
Malta
5-65
1*47
+ 1-90
— 1*68
+ 1-85
Simons Bay, Cape
of Good Hope
Yokohama, Japan
J 4-48
6-32
M7
1-65
MDCCCLXV.
f For British absolute units multiply by 3-83.
I For Foreign absolute units multiply by 1’76.
2 T
304
STAFF COMMANDER EVANS AND ME. A. SMITH ON THE MAGNETIC
ON THE EFFECT ON THE COMPASS OF PAETICULAB MASSES OF SOFT IRON IN A SHIP*.
The form of the general equations for the effect of the soft iron of a ship on the
compass does not, as we have seen, depend on the form, position, or inductive capacity of
the iron. They involve, it is true, nine coefficients which depend on these particulars,
but the data of the problem are in general not these particulars, but the effects which
they cause in certain definite positions of the ship. This is fortunate, because, while the
form of the general equations is obtained at once from very simple physical considera-
tions, and while the special formulae required are deduced from these by simple trigono-
metrical operations, and the coefficients are then deduced from the observations by a
simple arithmetical operation, the a priori determination of the effect on the compass
of given masses of iron is, in all but the very simplest cases, a matter of great and gene-
rally insuperable difficulty.
It is however in all cases interesting, and in some cases important, to be able to form
an approximate estimate of the nature and amount of the effects on the compass of
particular masses of iron, and although the precise cases of masses of iron in which the
problem admits of an exact solution may not often occur, yet cases frequently occur of
masses of iron sufficiently resembling them to have much light thrown on their effects
by the knowledge of the effect of the simpler bodies which they most nearly resemble.
The most general case for which the problem can be solved is that of ellipsoids and
ellipsoidal shells, including the forms into which these degenerate, as spheres, spheroids,
plates, cylinders, &c., but the general solution is so extremely unmanageable, in its
practical application, that it is more convenient to consider the simpler cases indepen-
dently. The cases which we shall consider are —
1. Infinitely thin rods of finite or infinitesimal length.
2. Infinitely thin plates of finite dimensions magnetized longitudinally.
3. Infinite plates of finite thickness magnetized perpendicularly.
4. Spheres.
5. Spherical shells.
6. Infinitely long cylinders magnetized perpendicularly.
7. Infinitely long cylindrical shells magnetized perpendicularly.
A little consideration will show that there is hardly any arrangement of iron in a ship
which does not bear more or less resemblance to one or other of these cases.
The physical theory of Coulomb, on which Poisson’s mathematical theory is based,
supposes, as is well known, that there is no separation of two kinds of magnetism except
within infinitely small elements of the iron ; but on this theory, if the iron be homoge-
* I beg to express my obligations to Professor W. Thomson for much of what is contained in this part of the
paper, and at the same time to express my hope that he may be induced to complete the promised Treatise on
the Mathematical Theory of Magnetism, part of which was published in the Phil. Trans. 1851. — A. S.
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 305
neons, the result on all external bodies is precisely the same as that of a certain distri-
bution of North and South magnetism on the surface of the iron.
To avoid the ambiguity which arises from the use of the terms “ North” and “ South”
magnetism, we shall speak of the magnetism of the north end of the needle and the
southern hemisphere of the earth as red magnetism, of the south end of the needle and
the northern hemisphere as blue magnetism.
I. An infinitely thin rod.
Let S be the area of a section of the rod, F the component of the earth’s force in the
direction of the rod, and x a coefficient depending on the inductive capacity of the iron.
Each end of the rod will have a quantity of free magnetism =«SF, the magnetism
being red at the north end, blue at the south end of the rod.
If x, y, z be the coordinates, r the distance of the blue end, A, y', z' the coordinates,
/ the distance of the red end, l the length of the rod, X, Y, Z the components of the
earth’s force, then the effect of the rod on a red particle at the origin is a force
Towards x=xS (jp—ps)
Y+ “-77-Z
To war
Towards
ds y=x S (y-y) j:
*-*x+/
iT+'-fl®,
-X+S^Y
If the rod be infinitely short, and x’ — x=dx, y' —y=dy, z1 — z—dz, l=ds, then force
Towards
dsl~x (x dx y dy z ds
1 2.
r ds'rds ' r ds
dx\(dx dy dz \
Towards y—x S-
dx y
ds
+
1 dJ) _M Jf x+§A+M
r ds 1 r ds J risj yds 1 ds ' ds y
Towards
If the rod be in the plane of x, y and parallel to the axis of x, then z, dy and dz— 0,
and force
Towards x-
Towards y = ^ 3fX,
Towards 2 = 0.
If the rod be in the axis of x, then x==r, and the force is
2 y^X in the direction of -\-x.
If the rod be in the axis of y , then #=0, and the force is
^Tf X in the direction of — x.
The. product «S£X is called the moment of the magnetic rod.
2 t 2
306 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
We will now pause to state what is known of the value of * for iron of different kinds.
The coefficient * is the quantity so designated by Neumann in Crelle’s Journal,
vol. xxxvii. p. 21, Weber in Gotting. Trans, vol. vi. p. 20, and Thalen in Nov. Act.
Soc. Reg. Upsal. 1861.
It is related to the Tc of Poisson’s papers in the fifth volume of the ‘ Memoires de
l’lnstitut,’ and to the g of Green’s celebrated “ Essay on the Mathematical Theories
of Electricity and Magnetism ” (Nottingham, 1828 ; reprinted in Crelle’s Journal,
vol. xlvii.), by the equation
47 r
— X
Green, in the essay referred to, finds, from some experiments of Coulomb on steel wire,
^=•986636,
whence
*=17-625.
Weber finds the following values of * :
Steel tempered to glass hardness and already magnetized . . . 4-091
Steel tempered to glass hardness with no permanent magnetism . 4-934
Soft steel 5-61
Soft iron 36
Thalen finds, from six specimens of soft iron carefully annealed, the following
values :
Specimen. x.
1 34-58
2
3
27-24
45-26
4 32-25
5 44-23
6 36-96
Mean . . . 36- 75
From observations of iron bars given by Scoresby in his 6 Magnetical Investigations,’
vol. ii. p. 320, we derive
X.
Iron rod, not struck 16-77
Iron rod, struck .... ... 44*07
From observations which we have made with a rod of iron x^-ths of an inch in dia-
meter, 3 feet long, we have found
X.
Iron, not struck . 1^-48
Iron, struck several sharp blows, about 80
Hence probably in the iron plates used in ship-building * may vary from 10 to 30.
CHAEACTEE OE THE AEMOUE-PLATED SHIPS OE THE EOYAL NAVY. 307
2. An infinitely thin plate of finite dimensions magnetized longitudinally.
If F be the component of the earth’s magnetism in the plane, and perpendicular to
any part of the edge, we shall have a distribution of red magnetism on the northern edge
of the plate, of blue magnetism on the southern ; and if m be the thickness of the plate,
then the force exerted by a part of the blue edge of length ds, or a red particle at a
distance r, will be
mds
and the effect of the whole edge will be given by ordinary integration. Such a plate
may in fact be considered as a collection of thin iron rods laid side by side, parallel to
the direction of the component of the earth’s force which we are considering.
3. An infinite plate of finite thickness magnetized perpendicularly.
Let F be the component of the earth’s force perpendicular to the plate.
The northern surface of the plate will have a distribution of red free magnetism, the
southern surface of blue ; the amount of each on an element of surface —dS being
1+47TX
<zs.
Each surface will exercise a force in a direction perpendicular to the plate of - F
on a red particle anywhere situate.
Hence the effect of the one surface, in the case of an external particle, will be to
neutralize the effect of the other.
On an internal particle, both surfaces acting in the same direction, the force will be
Al TX „
— I to South.
1+47 rx
4. Sphere.
The distribution of free magnetism on the surface of a sphere will of course be sym-
metrical with regard to two poles and an axis parallel to the direction of dip, the free
magnetism being red in the northern half of the sphere, blue in the southern ; the
amount on a unit of surface at either pole will be
I * — y
I + Itt* ’
and at a point at the extremity of a radius making an angle a with the axis
I cos u= — % — - . F cos a.
1+f™
The effect on a red particle at a distance r from the centre of the sphere, and in a
308 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
direction making an angle a with the axis, p being the radius of the sphere, is
1 +
4ir
~3: rr
(3 cos2 a — 1) to North ,
„3
F 3 sin a cos a from axis.
47T r3 J
1+¥*
Hence, at the pole, but outside the sphere , it is
8?r
Jx
——7 t”F to North.
1+T*
At the equator, and anywhere inside the sphere, it is
4.<7T}£
F to South.
The sphere, therefore, acts on external particles precisely as an infinitely small magnet
of moment . n3F held in the direction of the lines of force.
Here we may pause to observe the very remarkable fact that while the effect of a thin
rod or plate magnetized in a direction parallel to itself is nearly proportional to z, the
effect of a plate magnetized at right angles to its plane, or of a solid sphere, is almost
independent of the value of z.
Thus, taking Webee’s observations, the values of z for steel and soft iron are nearly
5 and 36. A soft iron rod or thin plate magnetized in the direction parallel to itself
would therefore have more than seven times the effect of a steel rod or plate of the same
dimensions ; but in the case of spheres the proportion of the effects would be
5 . 36 954 . .993
5-24 ' 36’24 * yy0
= 24 26 nearly;
or the effect of the hardest steel sphere is within 4 per cent, of the effect of a similar
sphere of soft iron, and within 5 per cent, of the effect of a similar sphere of a substance
infinitely susceptible of induction, and hammering such a sphere would make no per-
ceptible difference in its effect.
At the equator outside, and anywhere in the interior, the force of the sphere, as we
have said, is
4t»1
xF
to South;
1 + •
CHABACTEB OE THE AEMOUB-PLATED SHIPS OE THE EOTAL NAVY. 309
this force therefore would, within 5 per cent, in the case of a steel sphere, and within
1 per cent, in the case of a soft iron sphere, neutralize the effect of the earth’s magnetism.
5. Spherical Shell.
~Let p be the radius of the outer surface, q of the inner.
There will be a distribution of free magnetism on the outside similar to that on the
sphere, but in the case of the shell
, 8tt / , o3N
I=xF L-± 7 3.
47 r 87r c, /, q3
1+4"+t-sx (1_^.
There will be a similar distribution of free magnetism, but of the opposite kind, in
the interior surface, such that if I' represent the amount of blue magnetism on a unit of
surface at the north pole of the interior surface,
I'=*F
4tt 87T 2 / q3\
1+4” + s"Tx (1_?)
Hence for an external particle the coefficient will be
1 1
K-)
II
-s
1
, „ 4.7T 8t r
i+^'+T'T
P /
l-l
47 r
1 + T“
p ~ 87T7C
nearly, if x be large and 1 — ^ small.
If 1— ^ be infinitely small, the intensity both outside and inside at the North end
is = 1 + • F, or the same as in a plate, as might be expected.
Mr. Barlow found that in a shell of y^th o:
the effect was -f that of a solid sphere, whence
1
150 2
150 8ttx
112-5
or x—
7T
= 35-8,
which agrees closely with the previous results.
310 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
The coefficient for the force on a point in the interior of the spherical shell is
-T(I-I')
An
8?r / 1 ^
— x| 1 5
= -F
i_£+A
p 8nx
nearly, when z is large and 1 small ; and the Avhole directive force in the interior
will in that case be
1 +
tH)
and therefore if the shell be thick it will be nearly zero, the residual force being inversely
as the thickness ; if the shell be thin, the loss of force will be nearly proportional to the
thickness. <
6. Infinite cylinder , magnetized at right angles to its length.
Radius = jp.
The intensity of red magnetism on a point in the surface at an angle a from North is
_ xF cos «
i= 27TX+1 ‘
The effect on a red particle at a distance r, r making an angle a with the North and
South axis of a perpendicular section, is
— ■ ~FScos2«
2ttx + 1 rz
. to North,
Z7TX-}-l r*
fin 2os . . . to East.
7. Infinite cylindrical shell.
External radius jp, internal radius g.
The distribution of free magnetism will be similar to that on the solid cylinder,
except that, as in the case of a spherical shell, the free magnetism on the interior sur-
face will be of the opposite kind to that at corresponding points of the external surface.
For the external surface (red at North),
I=*F
1 + 2nx j
(*-
p*)
1
1 + 4ttx + 4ttV- |
(i.
1)
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 311
Internal surface (blue at North),
I'=*F-
1 + 4tx + 4 tt2x2
I1"?)
Hence for an external particle the coefficient will be J^I'^.
/ o2\ (l + 2wx)/l—
25r(I-I^)=25r*F « — LL
' P ' 1 + 4irx 4- 4tt5x2 / 1 — -
'H)
_ 2irxF p
~ 2ttx+1 £ 1
J9 + 2^
nearly, when * is large and 1 — ^ small.
In the interior of the cylinder the coefficient is
2 TTX
= — 2t*F.
H)
1 + 4?rx -f 4tt2;
= -F.
1-2+J-
p 2nx
nearly, if x be large and 1 — ^ be small ; or whole force in interior
1 +
2™^1-|
Application to particular cases.
As we know from the general equations that the effect of any masses of soft iron may
be represented by means of the coefficients a, b, c, d, e, f, g, h, k, and as we are in possession
of formulae which give the different parts of the deviation in terms of these coefficients,
by far the most convenient mode of expressing the effect of any given mass of soft iron
is to find the a, b, c , d , e,f, g , h , Jc to which it gives rise; and in what follows we shall
suppose the formulae involving these quantities and connecting them with the deviation-
coefficients to be known.
Thus from the expressions we have given for the effect of a finite or infinite rod, we
at once derive the coefficients a, b, c, they being the factors of X, Y, Z in the expres-
sions for the force towards x, and so of the others. From these we might derive the
coefficients 9(, SB, (S, T>, ($, K, x ; but there would be no interest in the general solution,
as the rods we have to deal with in practice are always parallel to one of the principal
axes, and these we shall therefore consider separately.
mdccclxv. 2 u
312 STAFF COMMANDER EVANS AND MB. A. SMITH ON THE MAGNETIC
Transverse longitudinal masses of Iron extending from side to side as Iron beams.
Let m be the length of the beam, or in general the breadth of the vessel, r the
distance of either end of the beam from the compass, S the area of the section of the
beam. It is easily seen that such a beam will give no coefficient except
xS m
Every such beam therefore diminishes the directive force and produces a + qua-
drantal deviation, the effect being directly proportional to the mass of the beam,
inversely proportional to the cube of the distance of its ends.
If we have a rectangle of four beams, two fore-and-aft and two transverse, the compass
being in or directly above or below the centre of the rectangle, l being the length of
the two fore-and-aft beams, m of the two transverse beams, we shall have
a=-2zSL
/
/
whence
X=1-^S
xs l — m
T ~r*-'
Such beams may be compared to the armour-plating of a ship, and we thus see that
for a compass near the centre of the ship, l being greater than m , the effect of such
plating will be to diminish the quadrantal deviation.
In accordance with this result, we find that in the wood-built iron-plated ships, when
the compasses are inside the rectangle of the armour-plating, the quadrantal deviation is
very small.
When, as in the case of the Warrior and Black Prince, the plating does not extend
from end to end, and the compasses are near or even outside one end, the case is
different.
Thus if the fore-and-aft coordinates of the ends be ad and x, and the distances from
the compass r' and r, we shall have
a=2*s{-^+*},
e=2*s{-^+^},
_ -As(x+y z'-y]
r3 “ r13 f
When the plating extends abaft the compass x is negative, and when this is the case,
ad being of course greater than y, so long as x is greater than y, or so long as the plating
CHARACTER Of THE ARMOUR-PLATED SHIPS OE THE ROYAL NAVY. 313
extends half the breadth of the ship abaft the compass , it will diminish the quadrantal
deviation.
When — | y—{rf —y)^m }»
or when the armour-plating extends a little less than half the breadth abaft the compass,
its effect on the quadrantal deviation vanishes, and when the distance is less than that
last mentioned, it increases the quadrantal deviation.
If the central part of a beam be cut out, and if y and y' be the transverse coordinates,
r, r' the distances of its outer and inner extremities from the compass,
«=2*s{=£+^}.
Hence if such a beam be near the compass so that it will increase the directive
force and diminish the quadrantal deviation ; if distant it will have the opposite effect.
A vertical rod, z being the vertical coordinate of the upper, z1 of the lower end, x and
y being the horizontal coordinates, will produce
c —%Sx (k—ptj ’
k =*S ^“3 *
The effect which is of most interest is that of k, as it affects the heeling error.
If z be negative, z1 positive, or if the upper end of the beam be above and the lower
end below the level of the compass, we see that k will be negative, and will in general
diminish the heeliug error.
If the rod be a short one of length n,
here k will be +, as
£> JL
r<*/3’
or, in other words, if the centre of the rod be within the cone traced out by a line
through the compass, making an angle of 54° 45' with the vertical, k will be positive,
and the force of the rod will act downwards and increase the heeling error. On the
other hand, if the centre of the rod be without the cone, k will be negative, and the
force will act upwards and decrease the heeling error.
Hence we see that in all cases, except when the compass is raised very much above
the upper part of the armour-plates, the effect of armour-plating will be to diminish the
heeling error.
2u 2
314 STAFF COMMANDER EVANS AND ME. A. SMITH ON THE MAGNETIC
Thin Plate magnetized in its plane.
If the compass be above or below the centre of a rectangular plate, which may repre-
sent the iron deck of a ship, lx being the length, 2 y the breadth, n the thickness, z the
height of the compass above it, r the distance from the compass to one corner, and v the
volume of the plate,
4 xnxy xv 1
4 xnxy xv 1
r.(y2 + £2)- V y* + z*'
1
2r\y+z2 a>2 + 2-2J
or such a plate will always produce a diminution of the directive force, and if x>y, or
if its length be in the fore-and-aft direction, a positive quadrantal deviation.
A vertical thin plate, such as a transverse bulkhead, may, as regards transverse
induction, be considered as a series of thin horizontal beams giving a — e, diminishing X
and increasing 3). As regards vertical induction, it may be considered as a series of
•vertical rods giving a -\-c if before the compass, a — c if abaft, and a -f- k or — 1c according
nearly as the centres of the supposed vertical rods are within or without the cone
we have described. There would be no difficulty in computing the effect of such a
bulkhead of given position and thickness if k were known.
Thick Plate magnetized perpendicularly .
If the length and breadth of the plate be infinite or very great compared to the
distance of the compass, such a plate will produce no effect on the compass, the effect
of one surface being exactly neutralized by that of the other.
When the dimensions of the plate are finite we may arrive at an approximate result,
by supposing lines drawn from the compass to every point on the edge of the further
surface. The parts of the two surfaces within the pyramid bounded by these lines will
neutralize each other, leaving only a margin of the nearer surface to act on the compass.
The effect of this may be easily computed, by computing the effect of four such red or
blue lines, as the case may be, the free magnetism in a unit of length being
F
— X breadth of margin.
From these considerations we see that the effect of even a thick armour-plating,
magnetized perpendicularly, will not be great.
The effect of a thick transverse armour bulkhead, on a compass immediately above
and near it, will be to produce a — a, which maybe easily computed, as we may suppose
the dimensions of the plate in every direction below its upper surface to be infinite.
If l be the thickness of the bulkhead, n the height of the compass above its centre,
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 315
Sphere.
Let the centre of the sphere be at a distance r from the centre of the compass, and
let r make angles a, (3, y with the coordinate axes to head, to starboard, and to nadir,
and let
4t r
3 3
PS-
An
M.
Then
a=M(S cos2 a — 1),
b=d= M 3 cos a cos/3,
whence
c=g= M 3 cos a cosy,
e=M(3 cos2/3— 1),
f=h= M 3 cos (3 cos y,
&=M(3cos2y— 1),
A =
1+y {1 — 3 cos2 y},
21=
o,
95 =
M 0 , .
— o cos a cos y tan 0,
(5=
M
— 3 cos (3 cos y tan 6.
2>=
y • (cos2 a — cos2 /3),
<$ =
— 3 cos a cos p,
From these we see that a sphere, wherever placed, will increase X and give a — k if
1
cos y<—
' V 3
or
y>54° 45',
and will decrease X and give a -\-k if y<54° 45'.
Hence if, as before, we suppose a double cone traced out by a line passing through
the compass, making an angle 54° 45' with the vertical, all spherical masses of iron
whose centres are placed without the cone will increase the directive force and diminish
the usual heeling error. All spherical masses whose centres are placed within the cone
will diminish the directive force and increase the heeling error. Hence, as far as pos-
sible, no iron should be either below or above the compass within an angle of 54° 45' of
the vertical passing through the compass.
If cos a > cos (3 , or if the centre of the sphere be in either fore-and-aft quadrant, the
316 STAFF COMMANDER EVANS AND. ME. A. SMITH ON THE MAGNETIC
effect of the sphere is to increase the quadrantal deviation ; if in the starboard or port
quadrant, it will decrease the quadrantal deviation.
If we have two spheres, one on each side and at the level of the compass, a =90°,
y=90°, j3=0° and 180°, whence
X=l+M,
3M
1+M'
1 +
(?)'
nearly.
Hence we get the following for the effect of two such spheres according to the
number of semidiameters which their centres are distant from the centre of the compass.
r.
e.
D.
2 V
•333
19 30
3 P
•107
6 10
4 p
•046
2 40
bp
•023
1 20
Hence also we find the distance of the spheres required to correct any given qua-
drantal deviation 2,
Ant
~3x
As we have supposed — ^-=1, the deviation which two balls of iron of the usual
1 +TX
kind will correct will be one or two per cent, less than the above.
When the sphere is in either of the diagonal planes, a=45°, |3=45°, or a= — 45°,
/3=135°,
2=0, and
or (S is the same as the 2 when the sphere is in a principal plane. This We should of
course anticipate.
M
From the expression 33= — 3 cos a cos y tan 0, we see that in the northern hemisphere,
if the sphere be below and before, or above and abaft the compass, we have a + semi-
circular deviation ; if above and before, or below and abaft, a — semicircular deviation.
Spherical Shell.
The effect, if the compass be exterior to the shell, will be precisely the same as that
of a sphere if for M we substitute
M
(i+H
ti
1 + Airx -f
4 8/
CHARACTER OF THE ARMOTJR-PLATEE SHIPS OE THE ROYAL NAVY. 317
or nearly, when * is large and 1 — ~ small,
i_2
l— i+— -
p own
Hence we see that the force of the shell will be half that of a sphere of equal
external radius if * be 12 and the thickness of the shell be y-jjo of the semidiameter,
or if *=24 and the thickness be 2-50 °f the semidiameter, or if *=36 and the thick-
ness of the shell be 3-^0 of the semidiameter.
Hence the effect of a tank ^th of an inch thick and 4 feet diameter would probably
be about one-third that of a solid mass of the same dimensions.
The effect of such a mass as a rifle-tower 4^ inches thick and 10 feet in diameter will
be nearly the same as if it were of solid iron. Such a tower placed in front of a compass,
as in the Warrior, will give a considerable +«, a — e of half the amount, and therefore
increase \ and 3D, and if the compass be neither much above nor below it, decrease the
heeling error.
Infinite cylinder magnetized perpendicularly to its length.
A compass placed at a considerable height above the deck, near an iron mast or
funnel, may be considered as acted on by a vertical cylinder or cylindrical shell of infi-
nite length. If r be the distance of its centre from the centre of the compass, p and ^
the radii of the outer and inner surfaces of the cylinder, then when the cylinder is solid,
M=
2wk p2
1 + 2wn r 2
and when the cylinder is hollow
M= 2™ v2
1 + 2ww r2
(1+2 w*y
H)
l + 4** + 4»V
H)
2wn p2 p
1 + 2 wn r2 q 1
p + 2wx
nearly, if * is large and 1 — ® small.
Also
a = M,
e = — M;
hence *
K = 1,
■ 2) = M;
whence we get the remarkable result, that a long vertical cylinder or a cylindrical shell
318 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
does not alter the mean directive force on a compass placed near its centre as regards
elevation.
It may be interesting to compare the effect of two solid stanchions placed one on
each side of the compass with that of two solid spheres, in correcting the quadrantal
deviation. The effect of the stanchions would be nearly
whence
r .
©.
D.
2p
•500
30° 0
•222
12 50
4 p
•125
7 10
5j>
•080
4 36
A mast or stanchion placed as we have supposed would generally diminish the heel-
ing error.
We may compare the effect on the directive force of a compass on the main deck of
an iron ship with the effect on a compass in the interior of a spherical shell.
In some ships the value of X at the main-deck compass is about *75.
Comparing this value with the expression for the force in the interior of a spherical
shell, viz.,
F
we have
or
taking * as 24,
1_2=J- ;
p 8irx
1
£_J_
p~ 600
nearly, or the effect is the same as if the compass were inclosed in a spherical shell of
an inch thick and 50 feet radius, or half an inch thick and 25 feet radius.
We may observe that at present one of the great difficulties in deducing numerical
results as to the effect of rods or plates of iron, arises from our ignorance of the value
of x for iron used for building or plating ships. We hope to be able on some future
occasion to be able to communicate to the Royal Society the result of observations
made for the purpose of determining this value in plates of iron of different kinds.
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 319
GENERAL CONCLUSIONS.
The following appear to be the principal conclusions to be drawn from the applica-
tion of observation and theory to the magnetic phenomena in iron ships.
1. The original semicircular deviation depends principally on the direction of the
ship’s head in building, and consists principally in an attraction of the north point of
the needle to the part of the ship which was (nearly) south in building.
2. This attraction is caused by the subpermanent magnetism induced in the ship
when building, by the horizontal force of the earth.
3. If we consider separately, first, the effect of the subpermanent magnetism induced
by the fore-and-aft component of the horizontal force, and secondly, the effect of the
subpermanent magnetism induced by the transverse component of the horizontal force,
the first is relatively less than the second. This, if the direction of the ship in building
does not coincide with a cardinal point, modifies the direction of the semicircular devia-
tion produced.
4. A third part, being the remainder of the semicircular deviation, is independent of
the direction of the ship in building. It is the effect of the subpermanent and transient
magnetism induced in the ship by the vertical force of the earth, and it consists in an
attraction of the north point of the needle to the bow or stern.
In the usual place of the Standard Compass this part is, in the northern hemisphere,
an attraction of the north point of the needle towards the bow ; but if the compass is
placed nearly in front of a large vertical mass of iron, as the stern-post, it may be
towards the stern.
5. The first and second parts of the semicircular deviation diminish rapidly after the
ship has been launched, the second generally most rapidly ; but after a time, which
may be taken roughly as a year, if the ship has been allowed to swing on all azimuths,
they attain a very fixed and permanent amount, from which they do not afterwards vary
to any great extent.
The third part changes little, if at all, so long as the ship remains in the same latitude.
6. The changes which take place in the semicircular deviation of a ship built East
and West are generally relatively greater than in one built North and South.
7. The transient magnetism induced by the earth’s horizontal force adds to the effect
of the subpermanent magnetism induced by the same force, when she is on the stocks,
and afterwards when her head is in the same direction in which it was while building.
8. The effect of the subpermanent and transient magnetism induced by the hori-
zontal force when the ship is on the stocks is principally, and if the ship is built on a
cardinal point entirely, to produce a diminution of the directive force on the needle,
and very little, and if built on a cardinal point not at all, to produce deviation.
9. The same effect (nearly) is produced at a subsequent time if the ship’s head is
placed on the direction in which it was while building.
mdccclxv. 2 x
320 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
10. This diminution of the directive force is greater if the ship has been built East
and West than if built North and South.
11. The deviations in an iron ship which has been built East or West are more preju-
dicial than in a ship built North or South in the following respects: —
1. They are less symmetrical and regular, and therefore more perplexing to the
seaman.
2. They change more relatively after launching.
3. They diminish the directive force more when the ship is on particular points.
12. When a ship has been built head North, the upper part of the stern and the
lower part of the bow are strongly magnetized ; the upper part of the bow and the
lower part of the stern are weakly magnetized. When a ship has been built head
South, the upper part of the bow and the lower part of the stern are strongly, the
upper part of the stern and the lower part of the bow are weakly magnetized.
Consequently in ships built head North, a compass placed near the stern will have a
large semicircular deviation.
13. In the last case there will be a large downward force on the north point of the
needle, which will produce a large heeling error. In ships built head South, both the
last errors will probably be small.
14. On the whole, for compasses to be placed in the after part of the ship, the best
direction for building is head South. For compasses near the centre of the ship, the
directions head North and head South are nearly equally good.
15. The diminution of the mean directive force is the mean of the diminution caused
by the transient magnetism induced by the horizontal force when the ship’s head is
North or South, and that induced when her head is East or West, i. e. it is the mean of
the thrust from the north end and from the north side.
16. The quadrantal deviation is caused by the excess of the latter over the former, i. e .,
by the excess of the thrust from the north side over the thrust from the north end.
17. The diminution of the directive force and the amount of the quadrantal deviation
are nearly the same at the same level in different parts of the ship. They increase in
descending from the position of the Standard Compass to the compasses on the upper
and main decks. They diminish with the lapse of time.
18. By substituting wood for iron in the part of the deck below and above the compass,
and within an angle of 35° 15' of the vertical line passing through the compass, and
having no masses of iron with their centres within 54° 15' of the same vertical line, the
directive force is increased and the quadrantal and heeling error generally diminished.
19. In selecting a place for the Standard Compass, care should be taken to avoid as
much as possible the proximity of the ends of elongated masses of iron, particularly
if placed vertically ; or, if they cannot be avoided, then a place should be selected where
they diminish instead of increasing the semicircular deviation.
The neighbourhood of rifle and gun turrets in ships carrying them should be as much
as possible avoided.
CHARACTER OF THE ARMOUR-PLATED SHIPS OF THE ROYAL NAVY. 321
20. In the construction of iron-built and iron-plated ships, regard should be had to
the providing a suitable place for the Standard Compass. It is not difficult for any one
who has studied the question, to suggest arrangements which would greatly mitigate the
injurious effects of the iron of the ship ; the difficulty is to reconcile them with the
requirements of construction and of working.
Postscript.
Since the foregoing paper was read, additional observations of deviations have been
made in the Achilles and Defence, and observations in two new iron-built armour-plated
ships, the Minotaur and Scorpion, the results of which are contained in the annexed
Table. The observations in the Achilles show a continued diminution in the value of
S3 and a continued tendency in 6 to return to its original value. The Defence con-
tinues to show great permanence both in 93 and (5.
The Minotaur, of which it has been thought desirable to give a woodcut drawn to
the same scale as the ships represented in Plate XI., illustrates in a very remarkable
manner some of the principles deduced from other ships. The Minotaur is the first
iron-built ship completely plated from end to end ; her quadrantal deviation is con-
sequently small. Having been built and plated head north, the original deviations in
all the compasses were very large. In the steering and poop compasses the maximum
deviation was above 60°. With deviations of this amount the compass becomes useless
unless corrected by magnets, and magnets were consequently applied, which removed
almost entirely the semicircular deviation. Probably in a very short time we shall find
the original — 93 of these compasses to have so far diminished that the compasses will
be found to be greatly over corrected and to have a considerable +93. Magnets were
also applied to the Standard Compass. The heeling error at the poop compass is very
large, 2° 46'. This arises from the compass being so near the stern of the ship, built
and plated head north, and also from its being elevated above the armour-plating. It
is interesting to contrast it with the heeling error of the steering compass, where from
the peculiar configuration of the armour-plating being such as to give a — Jc, the heeling
error is diminished and of a moderate amount.
The Scorpion is a remarkable instance of the change which takes place in the semi-
circular deviation from a change of position in a new iron-built vessel. Having been
built head N. 76° W., or S. 254° E., the original value of 93 was — ’246, and the original
starboard angle was 233-|°. After lying four months head S. 47° W. or S. 313° E., the
value of 93 changed its sign and became +‘225, and the starboard angle increased to
303A°, thus following very nearly the direction of the south line in the ship. The
Scorpion is an instance of the successful correction of the heeling error by means of a
vertical magnet. This reduced the heeling error from 1° 38' to 2; for each degree of heel.
2x2
STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC
322
Ship.
Compass.
Place.
Date.
Approximate coefficients.
Exact coefficients.
A
B
c
D
E
1
e ;
Minotaur.
(6621 tons),
1350 horse-power,
26 guns,
Iron-cased,
iron hull.
Built on same slip
as Warrior ; head
N. 3° E. magnetic.
Launched
Dec. 12, 1863.
Plated head
N. 22° E. in
Victoria Docks.
Scorpion.
(1857 tons),
350 horse-power,
4 guns,
Iron-cased turret
ship, iron hull.
Built at
Birkenhead ; head
N. 76° W.
Standard.
Victoria Docks, March 28, 1865 |
EiverThames, March 30, 1865 ...
Sheerness April 10, 1865 .. j
0 1
By denial
D of k
-0 47
-0 5
5
%on and h
larch 30 a
-23 26
-20 30
+ 0 44
° \
orizontal .
dopted ....
+ 64
+ 4 25
— 0 16
0 1
force on o\
+ 5 41
+ 5 43
+ 5 43
0 1
ne point : ,
-0 54
-0 26
—0 26 1
\ andj
II — -014
I--001
after coi
-•487
-•420
-•379
” reetion
+ •174
+•099
+ •069
by mag
+•100
+•100
nets.
-°
— 0(|
Starboard
steering.
Sheerness April 10, 1865 .. |
+0 32
-61 0
— 0 28
+ 0 45
+ 2 8
+ 5 56
-0 7 (
[+•009 | — *965
after correction
I+-015 | + -103
by magnets.
-■Olj
Poop (on fore
part),
Sheerness April 10, 1865 .. j
+1 16
-60 0
- 1 55
+ 20
+ 5.8
+ 4 55
-0 5 <
I+-022
after co7
( — ■948
•reetion
( + •038
by mag
I+-086
nets.
-•01 I
Standard.
Birkenhead . . . October 31, 1864
1 March 14, 1865 {
Birkenhead •!
[ March 15, 1865 j
By deviat
D of M
lapse of
From obse
been lyi
53 1
after com
ion and he
arch 1865
' time
nations n
ng four m
+ 0 32 |
’.ction by 7,
rrizontal J
adopted ,
lade in on
onths 8. 4
+ 1 43
rngnets.
rorce on 07,
with smal
e quadran
7° W.
+ 10 47
te point: )
'l allowanc
t after shq
-0 52
t and 1
•e for L
0 had~\^
-•015
-•246
+ •225
+ •009
-•355
-•341
+ •030
+-i9°(
+•180
+■187
mum
-•O'
Achilles
(continued).
Standard.
Portland April 1865
Lisbon May 4, 1865
+ 16 50
+ 12 30
+ 6 40
+•322
+•274
+•191
+ •132,
+•115
■■
..
I*
Defence
(continued).
Standard.
Portland April 3, 1865
Lisbon May 1, 1865
+0 13
+0 23
+ 20 19
+ 16 51
- 0 14
- 1 is
+ 6 09
+ 6 16
-0 36
+0 04
+ •004
+-o°7
+•367
+•307
-•004
— •021
+•107
+•109
-f Hi
+ ’1
7
CHARACTER OE THE ARMOTJR-PLATED SHIPS OF THE ROYAL NAVY. 323
R
imum of semicircular
deviation
VB2 + C2
Mean
force to
North,
X
t
1
X
Coefficients of
horizontal induction.
Part of D from
Mean
Vertical
force,
P
X
Heeling
coefficient
Heeling coefficients
from
9
tan 6 !
i
9
izontal force of ship
Vs82+®2*.
Fore-
and-aft,
a
t
Transverse
e
t
Fore-
and-aft
induction.
Transverse
induction.
to
windward,
X
Vertical
induction
in trans-
verse iron.
Vertical
force and
induction
in vertical
aount.
Direction.
O
0 1
0 /
° /
0 !
0 1
•516
1604
24
•432
1664
•876
1142
-•036
-•212
-1 12
+ 6 57
21
•385
1694
•892
1-121
-•019
-•197
-0 38
+ 6 51
1-442
.+ ] 21
+0 35
+0 46
61
■965
179
•811
1-233
-•106
-•272
-3 43
+ 9 42
1-091
+1 ?
+0 50
+0 17
6(
•950
177|
•826
1-211
-•103
-•245
-3 33
+ 8 30
1-660
+2 46
+0 46
+2 0
•434
2334
*8 10 as
sumed.
1-472
+ 1 39
•406
3034
1-636
+ 1 38
+ 1 02
+0 36
-•050
•838
1-193
-•037
-•350
-0 7
+ 10 57
( -826
+0 2
( after co
erection b\
y vertical
magnet.
|
•374
304
•844
1-185
-•059
-•253
-1 57
+ 8 38
/ ’3°6
(•384
} *6
■820
1219
-•086
— •274
“3 2
+ 9 37
2(
•367
3594
•875
1-143
-•031
-•219
-1 02
+ 7 13
If
(■308
(•387
} 356
•855
1-169
-•052
-•238
-1 46
+ 8 0
Mean force to North (AH) being unit.
t Earth’s Horizontal force (H) being unit.
I Earth’s Vertical force (Z) being unit. '
FhiL. Trouts. MDCCCLXK Flcct&X.
Phi b. Jrcune. MDCCCL Plata XT.
[ 325 ]
VI. On some Foraminifera from the North Atlantic and Arctic Oceans , including
Davis Straits and Baffin's Bay. By W. Kitchen Parker, F.Z.S., and Professor
T. Rupert Jones, F.G-.S. Communicated by Professor Huxley, F.B.S.
Received April 26, — Read May 12, 1864.
Table oe Contents.
§ I. Introduction : — Page
1. Soundings from Baffin’s Bay. (Table I.) 325
2. Dredgings from the Hunde Islands. (Table II.) 326
3. Dredgings from Norway. (Tables III. & IY.) 329
4. Soundings from the North Atlantic. (Tables V. & YI.) 331
5. General Remarks 334
§ II. Descriptions. Genera, Species, and Varieties. (Table VII.) 336
Descriptions of the Plates 412
Appendix I. — Additional North Atlantic Foraminifera 422
Appendix II. — Professor J.W. Bailey’s Researches on the “Virginian” Foraminifera of the North Atlantic.
(Table VIII.) 423
Appendix III. — Further Researches by Professor J. W. Bailey 428
Appendix IV. — Mr. Pouktales’ Researches on North Atlantic Foraminifera 429
Appendix V. — The Foraminifera of the “ Celtic” and “ Virginian” Provinces of the North Atlantic, as a
Fauna. (Table IX.) 430
Appendix VI. — Distribution of Foraminifera. (Tables X. & XI.) 434
Appendix VII. — The North- Atlantic Soundings. (Table XII.) 439
(Map [Plate XII.] and Plates XIII. to XIX.)
Introduction.
The specimens here described are comprised in four collections ; namely —
1. From Baffin’s Bay, between 76° 30' and 74° 45' North Latitude. These specimens
are derived from seven deep-sea soundings made during one of the Arctic Expedi-
tions under Sir Edward Parry. These soundings were confided to us by Professor
Huxley, of the Museum of Practical Geology, Jermyn Street, to which Institution
they had been given in April 1853 by Mr. J. W. Lowry, who received them of
Mr. Fisher, Assistant-Surgeon in the Expedition alluded to. The Foraminifera
obtained by us from these soundings are tabulated in Tables I., IV., and VII.
This material from the “Arctic Province” of Naturalists is but scanty. None of the
Foraminifera here obtained are numerous, except Polystomella striatopunctata, Nonionina
Scapha, Truncatulina lobatula, and Cassidulina laevigata ; the first two of which are at
home in Arctic waters : and none have attained here a large size except Lituolae. The
material from 150 fathoms yielded these relatively large and numerous specimens.
mdccclxv. 2 Y
326
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Table I. — Table of the Soundings from Baffin’s Bay.
No.
Depth.
Condition of bottom, &c.
Genera and subgenera of
Foraminifera.
fathoms.
1.
Lat. 75° 10', Long. 60° 12' . .
9
Pine grey syenitic sand, with
syenitic fragments j inch and less
in length.
Nodosarina (Dentalina), La-
gena, Planorbulina (Truncatu-
lina), Polystomella (and Nonio-
nina), Cassidulina, Miliola
(Quinqueloculina), Lituola.
2.
Lat. 76° 30', Long. 77° 52' . .
150
Greyish muddy micaceous sand,
with angular syenitic fragments
| inch and less in length.
Globigerina, Planorbulina
(Truncatulina), Pulvinulina,
Polystomella (and Nonionina),
Cassidulina, Lituola.
3.
Lat. 74° 45', Long. 59° 17'. .
250
Greysandymud; sand,quartzose,
angular and rounded.
No Foraminifera.
4.
Lat. 75° 25', Long. 60° ....
314
Syenitic sand, with fragments of
syenite | inch and less in length.
Miliola (Triloculina), Lituola.
5. •
Lat. 76° 20', Long. 76° 27' . .
2
No Foraminifera.
6.
Lat. 75°, Long. 59° 40' ... .
230
Grey mud, with quartzose sand,
partly rounded, and with several
partly rounded fragments of lava-
rock.
Planorbulina (Truncatulina),
Polystomella (and Nonionina),
Miliola (Quinqueloculina), Li-
tuola.
7.
Lat. 76° 10', Long. 76° ....
Sand from an iceberg. Grey,
heavy, fine, micaceous, syenitic
sand, with fragments (f in. largest);
some grains slightly worn.
No Foraminifera.
2. From the Hunde Islands, in South-east or Disco Bay, on the west coast of Greenland
(lat. 68° 50' W., long. 53° N.). Five soundings taken by Dr. P. C. Sutherland
(now Surveyor-General of Natal) in 1850, and confided to us by Professor
Huxley of the Museum of Practical Geology, to which Museum they were given
by Dr. Sutherland in 1853.
Dr. P. C. Sutherland’s observations on the Arctic Regions visited by him were pub-
lished in his ‘Journal of a Voyage in Baffin’s Bay and Barrow Straits in the years
1850-51,’ 2 vols. 8vo, 1852; and in the Quart. Journ. Geol. Soc. vol. ix. p. 296, &c.
See Tables II., IV., VII. for the Foraminifera from the Hunde Islands.
FOB A MIN IFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 327
Table II. — Table of the Dredgings and Foraminifera from the Hunde Islands,
Disco Bay.
No.
Depth.
Character of bottom.
G-enera and subgenera of Foraminifera.
1.
Hunde Islands . .
fathoms.
25 to 30
Pale-grey micaceous clay; more
Polymorphina, Planorbulina (Trunca-
2.
28 to 30
than half small mica-flakes. With
vegetable matter (fucal); Hydro-
zoa ( Sertularia ); Polyzoa ( Bereni -
cea, &c.); Entomostraca ( Cythere ,
&c.); Bivalve and univalve Mol-
lusks. (About an ounce.)
Gravel of hornblende-schist and
tulina), Pulvinulina, Polystomella (and
Nonionina), Nummulina, Cassidulina,
Bulimina, Textularia (andYerneuilina),
Cornuspira, Miliola (Quinqueloculina,
Triloculina), Lituola.
Globigerina, Planorbulina (Trunca-
3.
30 to 40
syenite (largest fragments 1| inch
long). Seaweed ( Fucus ) ; Nulli-
pores ; fragments of Balanus (pre-
dominant) ; Crustacea ( Talitrus ,
Cythere, <fcc.); spines and plates of
Echinus ; Polyzoa ; Univalves and
Bivalves. (About 4 ounces.)
Shelly sandy mud. Syenitic frag-
tulina), Pulvinulina, Discorbina, Poly-
stomella (and Nonionina), Cassidulina,
Miliola (Quinqueloculina), Lituola.
Nodosarina (Nodosaria, Cristellaria),
4.
50 to 70
ments (| inch and less), some
rather rounded ; fragments of Ba-
lani ; Serjoulce; spines of Echinus ;
Bivalves and Univalves. (About
2 ounces.)
Shelly fine sand (syenitic). Ser-
Lagena, Polymorphina, Uvigerina,
Globigerina, Planorbulina (Truncatu-
lina), Pulvinulina, Discorbina, Poly-
stomella (and Nonionina), Cassidulina,
Bulimina (and Virgulina and Boli-
vina), Textularia (and Yerneuilina),
Patellina, Trochammina, Miliola(Quin-
queloculina), Lituola.
Lagena, Polymorphina, Uvigerina,
5.
60 to 70
pula ; Bivalves and Univalves.
(About 1 ounce.)
Shelly sandy mud (syenitic).
Planorbulina (Truncatulina), Pulvinu-
lina, Discorbina, Polystomella (and No-
nionina), Cassidulina, Patellina, Miliola
(Quinqueloculina), Lituola.
Nodosarina (Dentalina, Cristellaria),
Serpula ; Balanus (predominant);
Bivalves and Univalves. (About
1 ounce.)
Lagena, Polymorphina, Uvigerina, Glo-
bigerina, Planorbulina (Truncatulina),
Pulvinulina, Discorbina, Polystomella |
(and Nonionina), Cassidulina, Bulimina
(and Virgulina and Bolivina), Textu-
laria (and Bigenerina and Yerneuilina),
Spirillina, Patellina, Trochammina,
Cornuspira, 'Miliola (Quinqueloculina,
Triloculina), Lituola.
Mr. G. S. Brady, of Sunderland, has examined the Bivalved Entomostraca from these
dredgings, and has determined the following : —
Cytheridea Bradii, Norman.
setosa, Baird.
Cythere costata, Brady.
protuberans, Brady.
plicata, Beuss.
Cythere clathrata, Beuss.
— septentrionalis, Brady.
Jonesia simplex, Norman.
Cytherideis pulcbra, Brady*.
* The new species of Entomostraca from the Hunde Islands, from Norway (p. 329), and from the Atlantic
(p. 334) are described and figured by Mr. Beady in the Zool. Soc. Trans, vol. v. part 5.
2 y 2
328
ME. W. K. PAEKEE AND PEOPESSOE T. E. JONES ON SOME
Shells, &c. from the Hunde Islands, Davis Straits.
(Dredged by Dr. Sutherland, October 1852 : named by Dr. S. P. Woodward.)
Box I. 28-30 fathoms.
Balanus porcatus, DO.\ probably : fragments much
crenatus, Brag. J water-worn.
Mya truncata. Fragment.
Saxicava arctica. Small valve.
Tellina calearia (=proxima =lata). Fragment.
Echinus, sp. Fragments of plates and spines.
Box II. 30-40 fathoms.
Leda minuta. Odd valve (large) and fry.
Crenella decussata. Small.
Limatula sulcata.
Astarte striata. Young.
semisulcata. Young.
Saxicava. Fry.
Eissoa castanea.
serobiculata.
Scissurella crispata.
Turritella lactea. Young.
Margarita undulata.
cinerea. Young.
Echinus. Small spine.
Spirorbis. Whorls furrowed.
Box III. 25-50 fathoms.
Saxicava arctica. Adult.
Lyonsia striata. Fry.
Astarte striata. Adult and fry.
Leda truncata. Fragments.
pygmsea. Fry.
Crenella decussata.
faba
Nucula tenuis. Fry.
Cardium elegantulum.
Natica pusilla (Groenlandica). Fry.
Cylichna Gouldii. Young.
Eissoa serobiculata.
Spirorbis.
Echinus. Spine.
Box IV. 50-70 fathoms.
Pilidium fulvum.
Acmsea. Fragment.
Chiton albus ? Two valves.
Astarte striata. Fry.
Spirorbis nautilus ?
. Sulcated.
Box V. 60-70 fathoms.
Pecten Islandicus. Fragments.
Mya truncata.
Astarte borealis, var. semisulcata. Young.
striata.
Saxicava. Fry.
Crenella decussata.
Limatula sulcata.
Turritella lactea. Fragment.
Eissoa castanea.
serobiculata.
Margarita helicina.
undulata. Fragment and fry.
cinerea. Fry.
Scissurella crispata.
Litorina obtusata. Fry.
Cemoria Noachina. Fry.
Pilidium fulvum.
Serpula.
Spirorbis.
Balanus porcatus . Tergum, and fragments of parietes.
Echinus. Fragments of spines.
The five specimens of sea-bottom above-mentioned, taken at depths of from 25 to 70
fathoms, and consisting mainly of shelly muddy sands, afford a good local example of
the Foraminiferal fauna of the “Arctic Province” of Naturalists, at the “Coralline-zone”
(15-50 fathoms) and the “ Coral-zone ” (50-100 fathoms) of Davis Straits.
Lagence abound in these dredgings at from 30 to 70 fathoms ; Polyrnorphino is small
here and rather common: Uvigerina common at from 30 to 70 fathoms, but small.
Globigerince are not rare at the same depths, but are very small. Truncatulina flourishes
at all the depths (25 to 70 fathoms). Pulvinulina is freely represented by the small
P. Karsteni. Discorbina gets more abundant with the greater depth. The simpler
forms of Polystomella , including the feeble Nonionince, have their home evidently in
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 329
this region. Cassidulina abounds, but is not large. A small Nummulina, the feeble
representative of a once highly potent species, still abounding in some warm seas, is not
wanting in the “Coralline-zone.” The essentially Arctic form of Bulimina (B. elegantis-
sima ) flourishes at from 30 to 70 fathoms at the Hunde Islands, and other varieties are
not wanting, though not abundant. The Textularice are represented by some small spe-
cimens of the type, and by three of its modifications in small but numerous individuals.
Spirillina is very rare and small. Patellina is small and common from 30 to 70 fathoms.
Trochammina is common, though small, in the deepest sounding. Cornuspira is common
at the least and the greatest depths. Quinqueloculina is common, but not large,
throughout. Triloculina occurs freely at 25 to 30 fathoms. Lituola abounds from 25
to 70 fathoms.
3. From the coast of Norway, between North Cape and Drontheim, from 69° to 63°
N. lat. Dredgings made by Messrs. MacAndrew and Barrett in the summer of
1855.
One portion of these materials* was received from the late Mr. Lucas Barrett, in
small boxes, numbered, and labelled with the depths and localities of the dredgings ;
another portion, received from Dr. Woodward, was the sandy refuse from a jar in which
specimens of Mollusks, &c. had been preserved in spirits ; and, thirdly, Dr. Bowerbank
favoured us with a packet of shelly sand obtained when preparing sponges taken in the
same dredgings. The latter lots of sand were manipulated and examined together^, no
particular depths and localities being noted for these mixed results of dredgings in from
30 to 200 fathoms.
The series of which the exact localities and depths are known comprises seven lots ;
these with their characters and contents are arranged in the following Table (No. III.).
The Bivalved Entomostraca from these dredgings have been determined by Mr. G. S.
Brady, as follow : —
Cythere Minna, Baird. Cythere catenata, Brady.
spinosissima, Brady. Cytheridea Bradii, Norman.
clathrata (varieties), Reuss. Cytherella Beyrichi, Reuss.
* These Norwegian Foraminifera have already been noticed and illustrated by us in the Annals of Nat. Hist.
2 ser. vol. xix. pp. 273, &c., pis. 10 & 11 (1857) ; we are, however, desirous of emending some of the
descriptions there given, as well as the nomenclature and classification in several points ; and these Foraminifers
are here brought into association with their allies of the neighbouring ocean.
f The specimens from this mixed material are grouped together in pi. 10 of the Ann. Nat. Hist. 2 ser. vol. xix.
330
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Table III. — Table of the Norwegian Dredgings and Foraminifera.
No.
Locality.
Depth in
fathoms.
Character of
sea-bottom, &c.
Genera, &c.
1.
East of EoLfs Oe, or Bred
Sound, Einmark. Lat. 71°,
long. 24°.
30
Gravel ....
Miliola (Biloculina, Quinqueloculina), Lituola, Poly-
morphina, and Planorbulina (Truncatulina and Ano-
malina).
2.
Omnoes Oe, Nordland (half-
a-milefrom the shore ; Wood-
ward’s 4 Manual,’ p. 434). Lat.
66° 45', long. 13° 25'.
40
Gravel ....
Miliola (Quinqueloculina), Planorbulina (Truncatu-
lina and Anomalina).
3.
West Ejord, Nordland.
About lat. 68° 15', long.
14° 30'.
60
Sand
Miliola (Quinqueloculina), Nodosarina (Dentalina),
Pulvinulina, Planorbulina (Truncatulina).
4.
Bodoe, Nordland. Lat. 67°
15', long. 14° 18'.
70-100
Sand
Miliola (Biloculina, Quinqueloculina), Planorbulina
(Truncatulina and Anomalina).
5.
Yigten Islands (Inner Pas-
sage), Drontheim. Lat. 65°,
47', long. 11° 5'.
100
On sponge .
Pulvinulina.
6.
Einmark (half-a-mile from
shore: see Woodward’s ‘Ma-
nual,’ p. 435).
150
Sand
Miliola (Quinqueloculina), Planorbulina (Trunca-
tulina).
7.
Arctic Circle, Nordland.
Lat. 66° 30', long. 12° 45'.
160
Mud
Miliola (Biloculina), Nodosarina (Glandulina, Nodo-
saria, Dentalina, Marginulina, Cristellaria), Planor-
bulina (Truncatulina and Anomalina).
8.
Yarious localities between
the North Cape and Dron-
theim.
20-300
Yarious . ,
Mihola (Quinqueloculina), Lituola, Lagena (and
Entosolenia), Nodosarina (Dentalina), Nummulina
(Operculina), Polystomella (and Nonionina), Discor-
bina, Spirillina, Planorbulina (Truncatulina and Ano-
malina), Globigerina, Polymorphina, Uvigerina, Cassi-
dulina, Bulimina, Textularia, Yalvulina.
The Norwegian Foraminifera are tabulated with those from Baffin’s Bay and Davis
Straits in Table IV., and with those from the North Atlantic in Table VII.
Mr. MacAndrew, who has kindly supplied us with latitude and longitude of the
localities in the foregoing list, informs us that “ these dredgings were all taken in shel-
tered situations among the islands and near shore ; occasionally a mile or two from land,
and frequently nearer. That at Omnoes Oe was made from the boat, and commenced
very near shore. The others in the list were made from the yacht, when we required
more room.”
Compared with the group of Foraminifera obtained at the Hunde Islands at similar
depths, those from the Norway coast present considerable differences ; and this is mainly
owing to the fact that the specimens given us from the seven Norwegian dredgings were
only the larger and more conspicuous of a probably rich fauna ; but also, partly, because
the coast of Norway (excepting the neighbourhood of North Cape) lies in the “Boreal
Province,” and is far less under the chilling influence of floating ice than the American
coasts to the westward. The dredging from Bolfs Oe was taken within the “ Arctic
Province.” The mixed sands obtained from the shells and sponges of Messrs. MacAndrew
and Barrett’s dredgings, and examined by ourselves, yielded many representatives of
the forms native to the Coralline- and the Coral-zone, though chiefly of small size.
The most interesting fact to be pointed out is the relatively great abundance of large
[Phil. Trans. 1865. To face page 330.
TABLE IV.— Distribution op Foraminipera in the Arctic Ocean, opp the Coasts op Greenland and Norway.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 331
Nodosarince , at 160 fathoms, just within the Arctic Circle,— such forms as are known
under the subgeneric names of Glandulina , Nodosaria, Dentalina, Marginulina, and
Cristellaria, and are abundant in some warm seas at less depths, and in the fossil state
in the Chalk and other deposits of Secondary and Tertiary age. Where the “ Celtic
Province” (under the name “Virginian”) impinges on the American coast of the
Atlantic, between lat. 30° and lat. 50° N., some soundings made by the Coast-survey of
the United States, at from 20 to 105 fathoms, yielded to Professor Bailey’s search
several Dentalince, Marginulince , and Cristellarice of good size. (See Appendix II.)
The Mollusca obtained by Messrs. MacAndrew and Barrett at Omnoes Oe, Nordland,
at from 30 to 50 fathoms, half-a-mile from shore (the dredging No. 2 in our list above),
are enumerated in Dr. Woodward’s ‘Manual of Mollusca, Recent and Fossil,’ p. 434;
and a list of the shells from an equivalent dredging to our No. 6 (if not the same) is
given at p. 435.
4. From the North Atlantic Ocean, between 52° 25' and 48° north latitude. Deep-sea
soundings in the North Atlantic between Ireland and Newfoundland, made in Her
Majesty’s Ship ‘ Cyclops,’ by Lieut.-Commander Joseph Dayman, in June and July
1857. See the Admiralty Report, with map and plates, and an Appendix by Pro-
fessor Huxley, 8vo, 1858. Thirty-nine of these soundings, from 43 to 2350 fathoms,
were examined. See Table V. and Map, Plate XII.
The materials confided to us were small portions (about thimblefuls) of thirty-nine
selected soundings, from out of a hundred and two.
This collection affords as fair an exposition of the Foraminiferal fauna of the parti-
cular tract of sea-bottom examined as the limited amount of material brought up by
the sounding-machine can be expected to give. The other materials (organic and inor-
ganic) besides Foraminifera are shown in Tables VI. & XII.
Three soundings, at from 43 to 90 fathoms off the coast of Ireland, at about 30 miles,
60 miles, and 75 miles off shore respectively (Nos. 39 [102], 38 [100], 37 [99]), indicate
the Foraminifera there inhabiting the “Coral-zone”; here th e Nodosarince are rare and
small ; Lagence rather more common ; Orbulina still more common ; Globigerina rare ;
the Rotalince ( Planorbulina , Discorbina , Rotalia, and Pulvinulina) are represented,
though not at all abundantly. Polystomella has its northern form (P. striatopunctata)
here and little else ; Cassidulina, Uvigerina, Bulimina, and Textularia are plentiful ;
Miliola and Lituola are comparatively poor both in number and size.
At different depths, ranging from 223 to 415 fathoms further westward along the
line of soundings, and nearly to the brink of the marginal plateau, this same fauna,
with some exceptions and a few additions, continues ; but Globigerina increases in size
and numbers; and so do Planorbulina TJngeriana and Pulvinulina Menardii , with its
subvariety Micheliniana.
Beyond and at the foot of the marginal plateau, the first sounding (15° & W. long.)
is at 1750 fathoms, and here we find very few Foraminifera, only Orbulina, Globigerina ,
Pulvinulina Canariensis, and Cassidulina , the two latter being small and rare. Further
332
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
westward, however, along the wide abyssal depths (to about 45° 30' W. long.), even at
more than 2000 fathoms, we find a larger fauna, of but few species, among which
Orbulina and Globigerina are characteristically abundant (especially the latter), and are
accompanied by Lagena (rare), Discorbina, Uvigerina, Rotalia Soldanii, Pulvinulina
Menardii, P. Micheliniana , and P. Canariensis, occasional specimens of Pullenia, a few
Nonionince and Polystomellce (P. striatopwnctata) , a few Rulimince, very few Textwlarice ,
and scattered small Milioloe and Lituolce . In the western portion of this territory the
fauna is somewhat poorer, where naturalists have drawn the southern portion of their
“ Boreal Province.”
Rising the western slope from the abyss (40° 45' to 49° 23' W. long., parallel to the
northern end of the Bank of Newfoundland), we enter the great southern angle of the
“Arctic Province,” and the Foraminiferal fauna continues to have much the same
elements ; but Globigerina and Orbulina have become rarer ; Miliolce are very rare ;
Planorbulina comes in, Pulvinulince disappearing after the first upslant of the bottom at
45° 45' W. long.
From 50° 14' 30" to 52° 44' W. long., we are still off the northern edge of the
Newfoundland Bank ; and, though the depth decreases from 405 fathoms to 161 and
then to 112 fathoms, Foraminifera are extremely rare, owing, without doubt, chiefly to
the coldness of ice-laden water. Truncatulina, Pulvinulina, Polystomella, and Uvigerina
seem to struggle for existence here, where “Arctic” conditions are extended southwards.
At 52° 56' and thence to 53° 57' 35" W. long, the line of soundings is in Trinity Bay,
with depths varying from 124 to 195 fathoms. Only very scarce Globigerince, a few
Pulvinulince, some Nonionince, rather more of the very persistent Cassidulince, and a very
few Uvigerince, Rulimince, and Lituolce appear to inhabit this unfavourable locality at
the depths examined. In fact this region belongs to the “ Arctic Province,” which is
here prolonged southwards towards the Bank of Newfoundland by the influence of cold
currents and icebergs.
With the exception of the westerly soundings, these deep-sea gatherings from the
North Atlantic illustrate the Foraminifera of the “Celtic Province”; but necessarily
lack, as a fauna, the complementary shallow-water forms, — namely, those living in the
Coralline, Laminarian, and Littoral Zones, at depths less than 40 fathoms.
The materials from Davis Straits (Hunde Islands) above-mentioned serve to illustrate
only for the “ Arctic Province” the Foraminiferal inhabitants of the Coralline-Zone ;
and therefore do not fulfil the requirements of this case. We may take, however, as a
term of comparison the list of the Recent Foraminifera of the British Isles, described by
Professor Williamson, but classified (and partly renamed) after the plan here adopted,
and augmented by later researches (including those by Mr. H. B. Beady, F.L.S.); and
we thus have before us, in these combined lists, a synopsis of the Foraminiferal fauna of
the “ Celtic Province.” (See Table IX. in Appendix V.)
The deep-sea Foraminiferal fauna of the North Atlantic differs from the fauna of the
Coralline, Laminarian, and Littoral Zones of the “Celtic Province” chiefly in having
fewer varieties and (generally) smaller individuals of Nodosarina, Lagena, Polystomella
TABLE VI.— Table showing the presence and proportion op Organic and Inorganic substances in 100 parts op dry sea-bottom prom the North-Atlantic. See also Table XII.
Arctic Pkovtjtce (Trinity Bay).
Arctic (North o
p Newfoundland Bank
:)•
Boreal (Abyssal).
Celtic (Abyssal).
Celtic (Marginal).
12
3
4
5
6
8
9
10
li
12
13
14
15
16
17
18
10
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
30
37
38
39
1 i
1
i
I
J
1
J
i
I
1
i
1
1
i
I
i
1
1
1
1
1
1
1
i
Q
i
1
1
1
2
1
2
1
2
i
i
i
1
i
j
J
,
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
doo
and Nonionina, Botalince , Bulimina, Textularia, Cornuspira, Miliola , and Lituola , and
no Polymorpliince ; and in having more Cassidulince and JJvigerinoe , and far more Globi-
gerinae and Orbulince , with the addition of Pullenia.
The Telegraph-line, in passing the northern end of the Bank of Newfoundland,
enters (at about 47° W. long.) the Southern extension of the “Arctic Province”*,
where the prevalence of floating ice keeps “ Arctic ” conditions as far south as 45°
N. lat. This western extremity of the line does not belong, therefore, to the
“Celtic,” but to the “Arctic Province”; and the few Foraminifera occurring there
may be regarded as equivalent to those mentioned above as being found at similar
depths in Bafiin’s Bay.
The south-western extremity of the “ Boreal Province,” bordering the “ Arctic,” also
invades the western part of the line of soundings f ; and is coincident with a somewhat
impoverished condition of the abyssal fauna common to these soundings (Nos. 21-26)
and others (Nos. 27-32) to the East (“ Celtic”).
The accompanying Map (after Commander Dayman’s Chart), Plate XII., illustrates the
foregoing remarks. See Appendix VII.
We are fortunately able to compare the deep-sea Foraminifera of the North Atlantic
with those inhabiting the shallower water of its western margin at a lower latitude than
Newfoundland, where the Telegraph-soundings terminate. The late Professor Bailey’s
examination^ of some soundings made by the United States Coast-survey on the shores
of New Jersey and Delaware, between lat. 50° and lat. 38° N., in 1848, affords us the
means of doing this, at least to some extent.
Where the “ Celtic Province,” crossing the Atlantic from the British Isles, approaches
North America, it takes on a modified character, and is known as the “ Virginian Pro-
vince”; and its north and south limits are just those of the series of soundings made by
the United States Coast-survey referred to above, and thus yielding us (as far as Professor
Bailey’s figures and descriptions serve) the western equivalents of the eastern margin of
the “ Celtic Province.” See Appendix II., and Table VIII.
As far as Professor Bailey’s material shows, we find the “ Virginian ” fauna to be
related to the “ Celtic ” of the Irish coast by Orbulina universa , Cristellaria cultratcc ,
Planorbulina TJngeriana (abundant in the Irish and rare in these American soundings;
whilst its congener, PL Haidingerii, abounds here and is wanting in the soundings off
Ireland), Pulvinulina Menardii, Globigerina bulloides , and Quinqueloculina Seminulum.
All the recorded “Virginian” forms occur in the British seas, except Marginulina regu-
larise Verneuilina triquetra, Bulimina Pyrula (represented to the eastward by B. margi-
nata) and Virgulina squamosa.
* See the Map of the Molluscan Provinces, by E. Foebes, in Iveith Johnston’s ‘ Physical Atlas’ ; the Map
in S. P. Woodwaed’s ‘ Manual of Mollusca’ ; and that in Foebes and Godwin- Austen’s ‘ Nat. Hist, of the
European Seas.’
t Soundings Nos. 26, 25, 24, 23,22, & 21. The last is close upon the southern limb of the “ Arctic Province.”
7 ®ee the ‘ Smithsonian Contributions to Knowledge,’ vol. ii. 1861.
MDCCCLXV. 2 Z
334
MR. W. K. PARKER MD; PROFESSOR T. R. JONES ON SOME
To the “Arctic” and “Boreal” faunge the “ Virginian ” is allied by Dentalina paupe-
rata , Cristellaria cult rata, Globigerina bidloicles, Bidimina Pyrula, VirguiinaSchrdbersii,
V. squamosa, and Quinqueloculina Semimdum.
Besides Foraminifera, the North- Atlantic soundings obtained by Commander Dayman
have yielded us the organic and inorganic materials indicated in Tables VI. & XII.
Mr. F. C. S. Roper, F.L.S., F.G.S., has obliged us with the following Note on the Dia-
tomacese *.
“3 Carlton Villas, January 7, 1864.
“•My dear Sir, — I regret that I have not before this replied to yours of the 24th ult., relating to the Sound-
ings I received from Mr. Parker. I mounted slides from each packet, hut found that they contained so few
Diatoms, that I only made cursory notes upon them; and, on referring to these, find they were almost confined
to specimens of Coscinodiscus, as you will see hy the list enclosed. These Atlantic soundings are so transparent,
and the siliceous matter apparently so wasted, that it is very trying to the eyes to hunt over a succession of
slides with high powers, to seek the few Diatoms contained in them ; and I was compelled from, the fear of
injury to my sight to abstain from an exhaustive examination of them.
“ Believe me very truly yours,
“ F. C. S. Roper.”
No. 45. Fragments of Coscinodisci.
No. 69.
No. 73. Large Coscinodiscus.
No. 79.
No. 86. Coscinodisci, a few.
The remainder little else than Foraminifera
and sand.
Sands.
No. 47. Coscinodiscus ? sp„
Rhabdonema.
Grammatophora marina.
No. 59. A few Coscinodisci.
No. 64. „
The remainder nearly all sand with Fora-
minifera.
The following Entomostraca from these soundings have been determined by Mr. G. S.
Brady.
Cythere scabra, Munster ; 2050 fathoms. Lat. 52° 16' N., long. 16° 46' V7.
rhomboidea Brady ; 43 fathoms. Lat. 51° 57' N., long. 10° 30' W.
mamillata, Bracly ; 110 fathoms. Lat. 52° 59' N., long. 14° 10' "V.
Bairdia Bosquetiana, Brady ; 470 fathoms ; off Ireland.
Clays.
No. 30. A few fragments of Coscinodisci.
No. 31.
No. 61. A large Cocconeis.
A few Coscinodisci, apparently 0., radiatus.
A Rhabdonema.
No. 63. A few fragments of Coscinodisci.
No. 85. Coscinodiscus. C. perforatus ?
No. 100. Coscinodiscus eccentricus.
Coscinodiscus radiatus.
Or thosira . marina .
Actinocyclus undulatus.
Pleurosigma transversale ?
No. 41. Coscinodiscus radiatus.
A Nitzschia.
A Rhabdonema.
5. Besides the description and illustration of the Foraminifera obtained from the four
sets of soundings and dredgings above mentioned, and the tabulation of the species and
varieties, showing their depth of water and relative size and abundance, we also point
* The Diatoms found in the “ Virginian Province ” are noticed hy Professor Bailey in the memoir above
referred to.
FORAMINIFERA FROM THE NORTH ATLANTIC AND AECTIC OCEANS.
odd
out, to some extent, their distribution in other seas (see Table VII.), and their occurrence
in the fossil state ; thus providing some materials towards a correct knowledge of their
distribution in Time and Space.
With this in view, we have endeavoured to simplify the nomenclature of the Forami-
nifera by adhering as strictly as possible to the plan of study laid down by Williamson* * * §
and Carpenter f, and followed by ourselves in former memoirs $.
Using the classification and nomenclature § proposed in the ‘ Introduction to the Study
of the Foraminifera,’ we have, under generic and specific heads, a limited number of
Fora mini feral groups, possessing among themselves very different features, whilst the
members of each group are formed on one simple plan, almost infinitely modified in its
details, and often producing imitations of members of the other groups, just as mimetic
resemblances occur in Mollusca, and in other Classes of the Animal and Vegetable
Kingdoms.
By recognizing these mimetic resemblances among distinct varieties and species, and
laying but little stress on non-essential features, we seem to be able to grasp the multi-
tudinous varieties and subvarieties, modified, disguised, and transitional, with something
like satisfactory results ; and they fall into natural recognizable groups, having more or
less fixed habits and places of growth, instead of escaping from us as an illimitable cloud
of differing though related individuals, almost unknown in reality, though nearly each
has been endowed by writers with a separate binomial title.
In determining the species and varieties of the Foraminifera under notice, we have, as
far as possible, used already published materials ; and in comparing our specimens with
figured forms, we have been satisfied when a near approach to identity is shown ; minute
differences are ignored, such differences not being of essential value.
There have been many naturalists who have helped on our knowledge of these Mi-
crozoa. D’Orbigny first classified them sufficiently well to enable himself and others
to group their acquired material in an orderly, though artificial manner ; and by his care
an enormous number of forms, specific and- varietal, from different parts of the earth,
recent and fossil, have been arranged in good lithograph plates, serving as a museum
for reference. Since D’Orbigny, few have collected such great stores of Foraminifera,
and illustrated them so abundantly, as Professor Dr. A. E. Reuss ; providing naturalists
with, as it were, available collections of hundreds of forms. Professor Reuss’s latest
observations have led him in a great degree to concur with (and in some cases to antici-
pate, we believe) the classification propounded in the ‘ Introduction to the Study of the
* On the Recent Foraminifera of Great Britain; by Professor W. C.Williamson, F.E.S. (Eay Society) 4to.
1858.
t Introduction to the Study of the Foraminifera ; -by W. B. -Carpenter, M.D., F.R.S., assisted by W. K.
Parker, Esq., and T. Rupert Jones, F.G.S. (Ray Society) 4to. 1862.
+ Papers on the Nomenclature of the Foraminifera, in the Annals of Natural History, from 1859 to 1863.
§ The concise and -well-digested remarks on classification and nomenclature in Dr. Woodward’s ‘ Manual of
Mollusca ’ are in great part applicable to Rhizopodal studies.
2 z 2
336
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Foraminifera.’ To D’Orbigny and Reuss, then, references will be continually made in
this memoir for illustrations of the species and varieties ; and the titles and dates of
their works, and of those of other authors treating of Foraminifera, are given in the
books and memoirs above mentioned, in which all the species adopted by the older
authors (Linne, Gmelin, Walker, Jacob, Montagu, Fichtel, Moll, Lamarck,
de Montfort, de Blainville, and Defrance) have been critically determined.
If ever the Foraminifera of all seas come to be collected and examined with care,
there is little doubt that they will afford to the Naturalist as satisfactory results as the
bathymetrical study of mollusks affords ; they will be perhaps even more useful to the
Geologist, in aiding him to form correct notions as to the depth and other conditions of
water in which strata have been formed ; whilst the accurate comparison of the long-
enduring Foraminiferal species of past and of present time, with their ever-varying
modifications, according to climate, depth, and food, cannot fail to be a source of in-
struction to the Biologist.
II. Description of Species and Varieties.
In the following list, the species and varieties described in this memoir are enume-
rated in their natural order as nearly as their nature permits ; the more important of
the typical forms not represented in the Arctic and North- Atlantic fauna, but required
to complete the series as a natural group, being added in brackets.
List of Genera, Species, and Varieties of Foraminifera from the Arctic and
North Atlantic Oceans.
Genus Nodosakina.
[Species. Nodosarina (Marginulina) Eaphanus.] Arctic.
Subspecies. N. (Nodosaria) Rapbanus
Variety. N. (Nodosaria) scalaris
N. (Glandulina) laevigata Plate XIII. fig. 1.
N. (Nodosaria) Radicula Plate XIII. figs. 2-7.
N. (Dentalina) communis Plate XIII. fig. 10.
Subvariety. N. (D.) consobrina
N. (D.) pauperata Plate XIII. figs. 8, 9.
N. (D.) guttifera PlateXIII.fig.il.
[Subspecies. N. (Yaginulina) Legumen.]
Variety. N. (Y.) linearis Plate XIII. figs. 12, 13.
[Species. Nodosarina (Marginulina) Eaphanus.]
Variety. N. (M.) Lituus Plate XIII. fig. 14.
[Subspecies. N. (Cristellaria) Calcar.]
Variety. N. (C.) Crepidula Plate XIII. figs. 15, 16.
N. (C.) cultrata Plate XIII. figs. 17, 18.
N. (C.) rotulata Plate XIII. fig. 19.
North Atlantic.
Plate XYI. fig. 1.
Plate XYI. fig. 2.
Plate XYI. fig. 3.
Plate XYI. fig. 4.
Plate XYI. fig. 5.
Species.
Species.
Species.
Species.
Species.
Species.
Species.
Species.
EORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 337
Genus Lagena.
Arctic. North Atlantic.
Lagena sulcata Plate XIII. tig’s. 24, 28—32. Plate XVI. tig’s. 6, 7 a.
Variety. L. globosa Plate XIII. tig. 37. Plate XVI. fig. 10.
L. Levis Plate XIII. fig. 22. Plate XVI. fig. 9 a.
L. semistriata Plate XIII. fig. 23.
L. striatopunctata Plate XIII. figs. 25-27.
L. Melo Plate XIII. figs. 33-36.
L. squamosa Plate XIII. figs. 40, 41. Plate XVI. fig. 11.
L. marginata Plate XIII. figs. 42-44. Plate XVI. fig. 12.
L. distoma Plate XIII. fig. 20.
Subvariety. L. polita Plate XIII. fig. 21.
Variety. L. caudata Plate XIII. figs. 38, 39. Plate XVI. figs. 7, 8, 9.
Genus Poltmorphina.
Polymorphina lactea Plate XIII. figs. 45, 46.
Variety. P. compressa Plate XIII. figs. 47-51.
P. tubulosa Plate XIII. fig. 52.
Genus Uvigerina.
Uvigerina pygmaea Plate XIII. figs. 53-57. Plate XVII. fig. 65.
Variety. U. angulosa Plate XIII. fig. 58. Plate XVII. fig. 66.
Genus Orbulina.
Orbulina universa Plate XVI. figs. 13, 14.
Genus Globigerpna.
Globigerina bulloides Plate XIV. figs. 1, 2. Plate XVI. fig. 15.
Variety. Gl. inflata Plate XVI. figs. 16, 17.
Genus Puelenia.
Pullenia sphaeroides Plate XIV. fig. 43. Plate XVII. fig. 53.
Genus Sph^eroidina.
Sphteroidina bulloides Plate XVI. fig. 52.
Genus Textularia.
Textularia agglutinans Plate XV. fig. 21.
Variety. T. abbreviata
T. Sagittula
T. pygmaea Plate XV. fig. 22.
T. carinata
T. biformis Plate XV. figs. 23, 24.
T. (Bigenerina) Nodosaria Plate XV. fig. 25.
Subvariety. T. (B.) digitata
Variety. T. (Verneuilina) polystropha .... Plate XV. fig. 26.
Plate XVII. fig. 76.
Plate XVII. fig. 77.
Plate XVII. fig. 78.
Plate XVII. fig. 79.
Plate XVII. fig. 80.
Plate XVII. fig. 81.
338
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Genus Btjlimina.
[Species. Bulimina Presli.] Arctic.
Variety. B. Pyrula Plate XV. figs. 8, 9.
B. marginata Plate XY. fig. 10.
Subvariety. B. aculeata Plate XY. fig. 11.
Variety. B. ovata ;
B. Buchiana
B. elegantissima Plate XY. figs. 12-17.
B. (Yirgulina) Schreibersii .... Plate XY. fig. 18.
Subvariety. B. (Yirgulina) squamosa Plate XY. figs. 19, 20.
Variety. • B. (Bolivina) costata
B. (B.) punctata
Genus Cassidtteiva.
Species. Cassiclulina laevigata Plate XY. figs. 1-4.
Variety. C. crassa Plate XY. figs. 5-7.
Genus Plahokbuxina.
[Species. Planorbulina farcta.]
Variety. PI. (Truncatulina) lobatula .... Plate XIY. figs. 3-6.
PL Haidingerii
PI. Ungeriana
PL Mediterranensis
PL (Anomalina) coronata Plate XIY. figs. 7-11.
Genus Discorbwa.
[Species. Discorbina Turbo.]
Variety. D. rosacea
[ Variety. D. vesicularis.]
Subvariety. D. globularis Plate XIY. figs. 20-23.
D. obtusa Plate XIY. figs. 18, 19.
[ Variety. D. Parisiensis.]
Subvariety. D. Berthelotiaha
Genus Eotalia.
Species. Eotalia Beecarii
Variety. E. Soldanii . .
Variety. E. orbicularis
Genus Pulvivulina.
[Species. Pulvinulina repanda.]
Subvariety. P. punctulata Plate XIY. figs. 12, 13.
Variety. P. auricula.
Variety. P. Menardii
Subvariety. P. Canariensis
P. pauperata
P. Micheliniana Plate XIY. fig. 16.
\Variety. P. Schreibersii.]
Subvariety., P. Karsteni Plate XIY.figs. 14,15,17.
Variety. P. elegans
North Atlantic.
Plate XYII. fig. 70.
Plate XYII. figs. 68, 69.
Plate XYII. fig. 67.
Plate XYII. fig. 71.
Plate XYII. figs. 72, 73.
Plate XYII. fig. 75.
Plate XYII. fig. 74.
Plate XYII. fig. 64 a, b,c,
Plate XYII. fig. 64 d.
Plate XYI. figs. 18-20.
Plate XYI. fig. 22.
Plate XYI. figs. 23-25.
Plate XYI. fig. 21.
Plate XYI. fig. 28.
Plate XYI. figs. 26, 27.
Plate XYI. figs. 29, 30.
Plate XYI. figs. 31-33.
Plate XYI. fig. 34.
Plate XYI. figs. 35-37.
Plate XYI. figs. 47-49.
Plate XVI. figs. 50, 51.
Plate XYI. figs. 41-43.
Plate XYI. figs. 38-40.
Plate XYI. figs. 44-46.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 339
Species.
Spirillum vivipara
Genus Spirillina.
Arctic.
Plate NY. fig. 28.
[Species. Patellina concava.]
Variety. Patellina corrugata
Genus Patellina.
Plate XY. fig. 29.
Genus Nummulixa.
[Species. Nummulina perforata.]
Subspecies. N. planulata Plate XIY. fig. 45.
[ Variety. N. (Operculina) complanata.]
Subvariety. N. (0.) ammonoides .... Plate XIY. fig. 44.
Genus Polystomella.
Species. Polystomella crispa Plate XIY. fig. 24.
Variety. P. arctica Plate XIV. fig. 25-30.
P. striatopunctata Plate XIY. figs. 31-34.
P. (Nonionina) Faba Plate XIV. fig. 36.
P. (N.) asterizans Plate XIY. fig. 35.
Subvariety. P. (N.) depressula Plate XIY. fig. 39.
P. (N.) stelligera Plate XIY. figs. 40, 41.
P. (N.)Scapha Plate XIY. figs. 37, 38.
P. (N.) umbilicatula .... Plate XIY. fig. 42.
P. (N.) turgida ;
[Species. Yalvulina triangularis.]
Variety. Y. conica
Genus Valvtjlina.
Plate XY. fig. 27.
[Species.
Genus Liiuola.
Lituola nautiloidea.]
Variety. L. Canariensis Plate XY. fig. 45.
L. globigeriniformis Plate XY. figs. 46, 47.
L. Scorpiurus Plate XY. fig. 48.
Species.
Genus Trochaio£isa.
Trocbammina squamata Elate XY. figs. 30, 31.
Variety. T. gordialis Plate XY. fig. 32.
Species. Cornuspira foliaeea
Genus Coenuspira.
Plate XY. fig. 33.
Genus- Miliola.
[Species. Miliola (Quinqueloculina) Seminulum] .... Plate XY. fig. 35.
Variety. M. (Q.) agglutinans Plate XV. fig. 37.
Q. Ferussacii Plate XY. fig. 36.
Q. oblonga Plate XY. figs. 34, 41.
Q. subrotunda Plate XY. fig. 38.
Q. tenuis
North Atlantic.
Plate XVII. figs. 62, 63.
Plate XVII. fig. 61.
Plate XVII. fig. 60.
Plate XVII. fig. 54.
Plate XVII. figs. 55, 56.
Plate XVII.' figs. 58, 59.
Plate XVII. fig. 57.
Plate XVII. figs. 92-95.
Plate XVII. figs. 96-98,
Plate XVII. fig. 87.
Plate XVII. figs. 85, 86.
Plate XVII. fig. 84.
340
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Arctic.
Variety. M. (Spiroloeulina) planulata
Subvariety. Sp. limbata
Variety. M. (Biloculina) ringens Plate XY. figs. 42-44.
Subvariety. B. depressa
B. elougata
[ Variety. M. (Triloeulina) trigonula.]
Subvariety. T. tricarinata Plate XY. fig. 40.
T. cryptella Plate XY. fig. 39.
North Atlantic.
Plate XVII. fig. 82.
Plate XVII. fig. 83.
Plate XVII. fig. 89.
Plate XVII. figs. 88, 90, 91.
Genus Nodosarina.
Several of the Nodosarine forms are well represented in the northern seas; but the
completion of this group of hyaline, straight, or more or less bent and coiled, uniserial
shells, flat, bulbous, cylindrical, or tapering, with simple septal apertures surrounded by
radiating fissures, such as are comprised in our great genus Nodosarina (with but one true
species), must be sought for in other seas. The larger Nodosarice and Cristellariae are
wanting here, as well as the Flabellince and Frondicularice, the Lingulince also, and a
host of variable Dentalince , Vaginulince , and Marginulinoe.
Nodosaria * Faphanus , Linne, sp. Plate XVI. fig. 1 (North Atlantic).
A dwarf sulcate specimen with the septal lines hidden ; ridges strong, oblique, and
inosculating to some extent. These are not unusual features in similar but larger spe-
cimens from the Mediterranean and elsewhere, occurring at from the shore-line to
100 fathoms.
Our specimen is from 78 fathoms, lat. 51° 59', long. 11°, North Atlantic, to the north
of Newfoundland Bank.
Nodosaria scalaris, Batsch. Plate XVI. figs. 2 a, 2 b, 2 c (North Atlantic).
A pretty, common form, neatly striated, subcylindrical, with more or less elongate
neck or stolon-tube. This is one of the varieties found by Soldani near Sienna
(Testaceogr. vol. i. part 2, pi. 95, figs, b-m), and named N. longicauda by D’Orbigny
(Ann. des Sciences Nat. vol. vii. p. 254, no. 28f. (See also page 353.)
Our figured specimens are from the North Atlantic; rare and small at 78, 90, 200,
222, and 415 fathoms (see Table V.). We have otherwise collected it principally from
muds from about 100 fathoms in the northern seas.
Nodosaria ( Glandulina ) laevigata , D’Orbigny. Plate XIII. fig. 1 (Arctic).
This is a smooth form, and rather slender compared with that figured by D’Orbigny
* For the relationship of species and varieties in the genus Nodosarina, of which Nodosaria represents a sub-
group, see the list at page 336.
t The priority of the name given by Batsch has been determined since this paper was read : see Arm. Nat.
Hist. March 1865, p. 225.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 341
in the ‘ Annales des Sciences Nat.,’ vol. vii. pi. 10, fig. 1-3; the ribbed form (N. Glcms ,
D'Orb.) is represented by D’Orbigny’s Modele, No. 51 ; both of these were from the
Adriatic, and were grouped in his subgenus Glandulina, characterized by the short and
acute-ovate shell, formed of few, close-fitting chambers, rapidly enlarging from the
primordial. Similar characters, but with less regularity, are found in many specimens
of Nodosaria Radicula, and therefore the term Glandulina is useful merely for conve-
nience in distinguishing the neatest of a great number of similarly modified forms, and
is nothing in a zoological sense.
Our specimens are from Nordland, in the Arctic Circle, at a depth of 160 fathoms
(Messrs. MacAndrew and Barrett) ; and they appear to be not uncommon, on a muddy
bottom.
This Glandulina occurs also, though never abundantly, in other seas ; for instance, on
the muddy bed of the Gulf of Suez at 30 to 40 fathoms ; in the Mediterranean, at from
30 to 100 fathoms (particularly in the Adriatic); and it has been found by Mr. H. B.
Brady in sea-sand from Shetland.
In the fossil state this form is not rare, though of extremely small size, as in several
of the fossiliferous clays of the Secondary Period (where it is apt to run, on the one
hand, into Lingulina , and, on the other, into Nodosaria Radicula), as in the Upper Tri-
assic Clay of Chellaston, the Oxford Clay of Leighton, the Kimmeridge Clay of Ayles-
bury, and in the Chalk-marl ; as also in the Tertiary strata of the Mediterranean area.
Nodosaria Radicula , Linn. sp. Plate XIII. figs. 2-7 (Arctic).
This is a Nodosarian variety closely related to the last, passing gradually from the
shape of a top to that of a pupa, or from a glandiform to a cylindrical shape, thus com-
prising Nodosaria humilis , Ifoemer, and many other named subvarieties. These allied
forms also lead out from Nodosaria proper to Dentalina ; the aperture being often
excentric and the axis curved. The several intermediate modifications of form have
received numerous binomial appellations from authors.
Fig. 4 presents, instead of the round aperture, a transverse slit. This is a character
supposed to be of generic value by D’Orbigny and special to Lingulina , this form of
aperture being connected generally with a flattened or tongue-shaped form of shell.
Here we have a specimen which dissolves the distinction between Nodosaria and Lin-
gulina.
Of the specimens here illustrated, figs. 2-6 are from Nordland (MacAndrew and
Barrett), 160 fathoms, muddy bottom. They are common (about a dozen specimens),
and of relatively large size. Fig. 7 is from Hunde Islands, Davis Straits, from a
bottom of shelly sand, at 30-40 fathoms (Dr. P. C. Sutherland).
These and numerous other closely allied forms occur in abundance in the Upper
Triassic and Liassic clays, and in the clays of the Oolitic formation, but usually they are
of very small size. In the Gault, Chalk-marl, and Chalk of the Cretaceous group, Nod.
Radicula and Nod. humilis , connecting it with Glandulina laevigata , are not uncommon,
mdccclxv. 3 a
342
ME. W. K. PARKER AND PEOPESSOE T. E. JONES ON SOME
and often of as large a size as those of the North Sea. In the Maestricht Chalk, also,
K Radicula is present and of moderate size.
Nodosarici ( Dentalina ) communis , D’Orb. Plate XIII. fig. 10 (Arctic).
This specimen is a dwarf Dentalina communis * of D’Orbigxy. The obliquity of the
chambers in this shell begins early, and so does the greater excentricity of the aperture.
This style of growth is well represented also by D. inornata, D’Orb. For. Foss. Vien.
pi. 1. fig. 51, and still better by D. Dadenensis, D’Orb. Ibid. pi. 1. figs. 48, 49; both of
which are well-grown specimens of D. communis.
Our figured specimen is from mixed shelly sands dredged up at various spots between
Drontheim and the North Cape by Messrs. MacAndrew and Barrett. It is very small,
and resembles what is usually found in nearly any muddy sand containing Foraminifera.
Dentalina communis is an extremely common variety wherever Nodosarian forms occur
in the clays of the Secondary Formations, but usually it is of small size. It is larger in
the Gault than in the Jurassic clays ; still larger in the Chalk-marl and Chalk, and in
the Maestricht Chalk, as well as in the Tertiary beds that yield Nodosarince. It is very
large in the Crag of Suffolk, and in the Subapennine Tertiaries. Older than the
Secondary deposits, however, it is found in the Permian limestones of England and
Germany.
It is common in the recent state from the Arctic Circle to the Line ; in fact, geogra-
phically and geologically, it has a very large range. It occurs in many sandy shore-
deposits; but its favourite habitat is mud at 50-100 fathoms; and is continually met
with in the deepest soundings, although never abundant there, and generally small.
Nodosaria ( Dentalina ) consobrina , D’Orbigny. Plate XVI. fig. 3 (North Atlantic).
Two joints of Dentalina communis , subvar. consobrina , D’Orb. (For. Foss. Vien. pi. 2,
figs. 1-3) ; the chambers are longish and set on more squarely than in D. communis
proper ; representing a passage into D. oviculcc, D’Orb. (D. globifera, Batsch).
This is small and rare at 1776 fathoms in the North Atlantic, lat. 52° 33', long. 21° 16'.
Nodosaria ( Dentalina ) pauper at a, D'Orbigny. Plate XIII. figs. 8, 9 (Arctic).
We have here a very common subvariety of Dentalina communis , in which the pri-
mordial chamber is relatively large, the septa but slightly oblique, and the aperture
almost central ; the shell is smooth, nearly cylindrical, and not constricted at the septa
in the earlier portion of the shell (as shown in our figures 8 and 9) ; as the animal
advances in growth, the chambers take on a more vesicular shape. D. pauperata, D’Orb.
For. Foss. Vien. pi. 1. figs. 57, 58, is the same as our figured specimens; and D.
brevis, D’Orb. Ibid. pi. 2. figs. 9 and 10, and many other named forms, are scarcely dis-
tinguishable.
* Annales des Sc. Nat. vol. vii. p. 254, No. 35 ; Mem. Soc. Geol. Prance, iv. p. 13, pi. 1. fig. 4.
EOEAMINIFEEA EEOM THE NOETH ATLANTIC AND AECTIC OCEANS.
343
Somewhat rare; from shelly sand, Hunde Islands, Disco Bay (Dr. P. C. Sutherland),
at 60-70 fathoms; also from Baffin’s Bay, lat. 75° 10' N., long. 60° 10' W. (Parry’s
soundings).
Nodosaria ( Dentalina ) guttifera , D’Orbigny. Plate XIII. fig. 11 (Arctic).
Passing out of Dentalina communis towards the perfectly moniliform subvarieties of
Nodosaria, we have this loosely grown Dentaline form (D. guttifera, D’Orb. For. Foss.
Vien, pi. 2. fig. 13), near D. Pyrula, D’Orb. It varies much in the gibbosity of the
chambers.
Though curved, this Dentalina has an almost central aperture, as shown by a broken
terminal chamber not here figured. (See Ann. Nat. Hist. 2 ser. vol. xix. pi. 19. figs. 4, 5).
We have Dentalina guttifera from Norway at West Fjord (Nordland), from a sandy
bottom at 60 fathoms (MacAndrew and Barrett) ; and from a muddy bottom (Arctic
Circle) at 160 fathoms. These are two fragments of two large specimens. There is
no doubt that in this, as in other instances, the small quantity of materials obtained
necessarily limited the number of individuals.
Forms similar or allied to this occur both in existing sea-bottoms and in fossil deposits
with much the same range as that of D. communis ; but they are not so common.
Vaginulina linearis , Montagu, sp. Plate XIII. figs. 12 a, 12 b, 13 a, 13 b (Arctic).
The straight varieties of Marginulina Baphanus (or the flattened forms of Nodosaria
Baphanus, with excentric septal apertures) are known as Vaginulince ; a large group,
widely extending in time and space ; especially abundant in the Gault and Chalk-marl.
Of these Vaginulince, V. Legumen, Linn., is the most common among the recent ; and
the Adriatic Sea may be said to be its home. The subvarieties with linear costation
are very variable as to their amount of ornament; but they may be all comprised under
Montagu’s name V. linearis. (See Williamson’s ‘ Monograph Recent Foram. Great Britain,’
p. 23, pi. 2. figs. 46-28.)
We have two small specimens from the mixed sands dredged up between Drontheim
and North Cape (MacAndrew and Barrett).
This is not an uncommon form, occurring at moderate depths. It does not appear to
be so common in the fossil as in the recent state, though it is not without close allies in
the clays and other deposits of the Secondary and Tertiary formations.
Marginulina Lituus, D’Orbigny. Plate XIII. figs. 14 a, 14 b (Arctic).
One of Soldani’s figured Foraminifera from the Adriatic, named Marginulina Lituus
by D’Orbigny (Annales des Sciences Nat. vol. vii. p. 259. No. 11), well represents our spe-
cimen from the Arctic Ocean. This may be looked at as a passage-form from a simple
Vaginulina, oval in section and but little altered from Dentalina, into Cristellaria, through
innumerable gentle gradations ; or it may be regarded as a medium between Cristellaria
and Marginulina ; and so leading to Nodosaria, through the flattened forms. Having
3 a 2
344
MR. W. K. PARKER AND PROEESSOR T. R. JONES ON SOME
the chief Nodosarine characters, the Marginulince form the central group of the Nodo-
sarince, and Nodosarina ( Marginulina ) JRaphanus is the type of all.
Very large specimens of M. Litnus occur at Nordland, Arctic Circle (Mac Andrew and
Barrett), on a muddy bottom, at 160 fathoms. These are the largest individuals we
have ever seen of this common variety of Marginulina or uncoiled Cristellaria, which
is to be met with wherever the Cristellarians occur, recent or fossil, from the Lower ,
Secondary deposits upwards.
In this case Cristellaria cultrata is also present ; and an analogous companionship of
the Cristellarian and the Marginuline Nodosarince is to be found in Professor Bailey’s
“Microscopical Examination of Soundings made by the United States’ Coast-survey off
the Atlantic Coast of the United States” (Smithsonian Contributions to Knowledge,
vol. ii. 1851), where two forms ( Nobulina D'Orbignii and Marginulina Bacheii, Bailey),
equivalent to the above, accompany each other in soundings of from 51 to 90 fathoms.
(See above, page 331, and Appendix II.)
Cristellaria Crepidula , Eichtel and Moll, sp. Plate XIII. figs. 15, 1 6a, 16 5 (Arctic);
Plate XVI. fig. 4 (North Atlantic).
We have here a very insensible gradation from Marginulina Lituus (fig. 14). In fact
fig. 15 differs but little from the latter except in size; and fig. 16 is merely somewhat
more closely coiled, flatter, and shorter ; thus putting on the true Cristellarian form.
These specimens are from dredgings made at the Hunde Islands by Dr. P. C. Suther-
land ; they are rather common in the sandy mud, rich with shells, at from 30 to 40 and
60 to 70 fathoms.
In recent occurrence C. Crejtidula is as world-wide as the ordinary Bentalince. It is a
feeble form of Cristellaria creeping up from the favourite depth of Cristellariae (50 to 100
fathoms) to shallow water, and downwards to abyssal deeps.
In the fossil state also it has an equally wide range ; but, like its congeners, it is met
with of a larger size in the Upper than in the Lower Secondary deposits. The largest
are to be found in the Subapennine and Viennese Tertiaries ; some of these large fossil
varieties are extremely thin.
Plate XVI. fig. 4 (North Atlantic).
A pretty little C. Crepidula , differing only as an individual from fig. 16 in Plate XI.
Small and rare at 43 fathoms, lat. 51° 57', long. 10° 30', North Atlantic.
Cristellaria cultrata, Montfort, sp. Plate XIII. figs. 17 a, 17 b, 18 a, 185 (Arctic);
Plate XVI. fig. 5 (North Atlantic).
This is Cristellaria proper, the most nautiloid form attained by any Nodosarina. Here
the rod-like chain of chambers seen in the simple forms ( Nodosaria ) has passed into a
spiral, discoidal, symmetrical, lens-shaped shell ( Cristellaria ). In this variety, C. cul-
trata, the shell is more or less keeled ; this keel becomes more developed and rowelled
EOEAMINIEEEA 1'EOM THE NOETH ATLANTIC AND AECTIC OCEANS. 345
in C. Calcar , Linn., sp. When the keel is wanting, we have Cristellaria rotulata , Lamarck.
There are no specific differences in their features.
Fig. 18 shows an irregularity of growth, and a disposition to depart from the nauti-
loid form towards the simpler varieties in which the greater distinction of the chambers
is preserved. Several angles around the periphery of the shells are sometimes formed,
rendering their outline polygonal. Other variations of growth are not uncommon ; the
polymorphism of these simple organisms being very great.
Plate XVI. fig. 5 (North Atlantic).
A smallish nautiloid Cristellaria with moderately developed keel, such as fig. 17 of
Plate XIII., but differing in the non-essential features of greater obliquity of chambers
and more distinct umbilical knob.
Rare at 78 fathoms, lat. 51° 59', long. 11°, North Atlantic.
Cristellaria rotulata , Lamarck, sp. Plate XIII. fig. 19 (Arctic).
Here the keel is nearly obsolete. This carina is generally all that is left to us in
these nautiloid forms of the longitudinal striae or costae that so frequently ornament the
subspecies of the large Nodosarina group. Occasionally, however, the lateral faces of
the shell bear raised costae crossing the chambers, nearly at right angles, as in the ribbed
Nodosarice and Marginulince (typical), and in many Vaginulince , Flabellince, and Fron-
dicularice.
The Cristellarice represented by figs. 17-19 occur, common and large, in the Arctic
Circle, Nordland, on a muddy bottom at 160 fathoms.
These recent northern specimens are, as regards size, equal to such as we find in those
rich Cristellarian deposits, the Chalk and Chalk-marl. Like the rest of this group, how-
ever, the largest of this form are found in the Subapennine Tertiaries, the Vienna
Basin, and in the Tertiary beds of Jamaica and San Domingo. Exactly similar speci-
mens of Cristellarice abound in the rich shelly bottom, at 50 fathoms, in the Port of
Orotava, in the Canaries ( Bobulina Canariensis , D’Orb. For. Canar. p.127, pi. 3. figs. 3, 4);
and forms nearly as large are not at all uncommon in the Mediterranean, especially in
mud at from 50 to 100 fathoms. In the Adriatic, however, this, with other Cristellarice ,
is found of similar size in shallow water.
Of small size, these are found on our own coasts and throughout all seas. They are
fossil in very many Secondary and Tertiary deposits, but of rather small size in the
older strata ; nevertheless in these latter beds they are exceedingly abundant and charac-
teristic, not being mixed so much with species of other families of Foraminifera that
have come in at a later epoch.
Genus Lagena.
For full descriptions, general and special, of this genus we refer to Professor Wil-
liamson’s Memoir on Lag ence, Annals Nat. Hist. 2 ser. vol. i. 1848; and his ‘Mono-
346
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
graph of British Recent Foraminifera,’ 1857 ; to Dr. Carpenter’s ‘Introduction to the
Study of Foraminifera,’ 1862 ; and to Professor Reuss’s ‘ Monographic der Lagenideen,’
Sitzungsber. Akad. Wiss. Wien, vol. xlvi. 1 Abth. 1863 (read June 1862); and for the
strict determination of the species noticed by Walker, Jacob, and Montagu, and for
some special remarks on Lagence , we refer to our own Papers .in the Annals Nat. Hist.
1857, &c.
On account of their extreme variability (within certain limits) as to shape and orna-
ment, without any definite break in the range of the modifications being recognizable,
it is impossible to fix on any distinctive character, or set of characters, sufficiently
limited in development to be of real importance in dividing the Lagence into even two
species. For convenience, however, we must take the best marked shapes and ornaments
as indicating subordinate or varietal types, around which the diverging modifications
may be grouped in an artificial classification.
This has been nearly completely accomplished, in his “ Monographie ” above referred
to, by Professor Reuss; who, however, regards these subordinate divisions as “ species.”
The addition of some striking varieties chiefly found in the warm seas, including the
two-mouthed elongate forms, and the correction of some errors in the synonymy, arising
mainly from mistakes as to Walker’s and Montagu’s Lagence , would still further
improve Professor Reuss’s classified and illustrated conspectus, of the chief members of
this group of elegant little single-chambered Foraminifera; and, without doubt, his
so-called “genus” Fissurina is open to criticism, as we shall see further on.
Lagena , including both those that have external apertural tubes (Ectosolenian) and
those with internal neck-tubes (Entosolenian), have their chief features of shape and
ornament shown by globose, ovate, and fusiform shells, either smooth, partly or wholly
ribbed, reticulate, or granulate and spinose ; also by more or less compressed shells, of
round or oval outline, with and without linear and reticulate sculpture ; further, the
base of the shell, opposite to the aperture, becomes apiculate, produced, and perforate,
in any of the above-mentioned kinds of shell, resulting in a more or less fusiform and
perforate, or clistomatous, condition.
Taking the smooth forms, varying from egg-shaped to flask- and amphora-shaped, with
or without long necks, we have the “ lsevigatee” of Reuss, among which L. globosa,
Walker and Jacob, L. Icevis, Montagu, and L. clavata , D’Orbigny, represent the three
best-marked stages. Reuss includes also the apiculate smooth forms in this group ; but
we prefer to bring them into relation with the perforate forms, to which we believe they
strongly tend.
Those with furrows, riblets, and ribs are the “ striate aut costate ” of Reuss. They
are led by L. semistriata , Williamson, from out of the smooth forms up to L. sulcata ,
Walker and Jacob, and even more coarsely ribbed shells, with modifications of form
exactly corresponding to those of the smooth varieties ; but no particular stage of shape
and of ornament can be said to be permanently associated.
In the “reticulate” (Reuss) the longitudinal riblets become united by cross-bars, of
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 347
varying strength ; either regularly, so as to form rectangular meshes (L. squamosa , var.
catenulata, Williamson, and L. Melo , D’Orbigny; or less regularly, and forming —
1st, either tetragonal or hexagonal network, with the meshes one above the other from
the base to the top of the shell, and divided by nearly straight longitudinal ridges or
walls; 2ndly, hexagonal network, with the meshes alternately placed (honeycomb-
pattern), the walls being zigzag, and equally developed along and across ( L . squamosa ,
var. Jiexagona , Williamson). Lastly, hexagonal and quadrangular meshes are combined
on one shell, as in L. squamosa , Montagu, sp., which herein well serves as the subtype.
The “ asperse” of Reuss are such as are ornamented with granules and spines. These
exogenous shell-growths are, without doubt, equivalent to linear and reticulate ridges,
variously modified; just as hispid Nodosarince show gradual modifications of riblets and
spines. As with the “ costatse” and the “ reticulatse,” no particular shape of shell speci-
ally afiects this style of ornament. Reuss’s “compressse” comprise the more or less
flattened Lagence , and must include those which he separates under the name Fissurina
on the supposition that they are distinguishable by their slit-like aperture. All
Lagence that are more or less compressed have the aperture correspondingly narrowed
and outdrawn, just as all Nodosarice becoming flattened and “Linguline” have a more
and more chink-like aperture. The transitions are extremely gradual both into “Fis-
surina” and “ Lingulina” respectively, and are associated indiscriminately with all the
other modifications of outline and ornament that belong to the species. The com-
pressed Lagence usually take on one or more keel-like riblets at or near the margin,
representing the local accumulation of the linear exogenous shell-growth so common in
Lagena. A similar feature occurs in the Nodosarince, where a similar ornamentation
obtains.
Lastly, we propose to complete this artificial classification of the Lagence , by dividing
oif those that, passing from a pointed or apiculate shape at the base, ultimately present
a perforate or distomatous, continuously tubular shell, more or less fusiform. Keuss’s
L. ctpiculata represents the smooth apiculate forms; D’Orbignt’s L. ccmdata the ribbed
ones; our L.polita the smooth, and our A. distoma the costulate, perforate forms. (See
Scheme of the Lagence , p. 348.)
Of Lagena it may be said, that, though apparently one of the simplest of Foramini-
fera, it is not one of the oldest, as far as our knowledge serves us at present. Nor can
it be regarded as an arrested Nodosaria;. rather, it may be looked on as a higher
specialization of the simple repetitive Nodosarian form. It has its isomorphisms, with
Nodosaria , both in ornamentation and in its flattening.
All the large Lagence are found at about 50 fathoms (25-70) in shelly sands; the
more delicate forms occur both in shallow water (which may even be brackish), in the
dark muds of harbours and bays, and, on the other hand, at great depths, being not
uncommon in the deposits almost wholly composed either of Foraminifera alone, or of
these with Pteropods.
348
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Scheme of the Lagex^e.
/-egg-shaped
smooth j flask-shaped
Lamphora-shaped .
f partly . .
delicately
strongly .
ribbed
Single- ,
mouthed '
coarsely
square meshes
reticulate 6-sided meshcs
I both 4- and \
Lfl-sided meshes J
rough-
(_ ened
J spines . .
1 granules
f smooth . .
compressed
striate
r
reticulate
l_3-keeled
f short . .
Passing
from
appendi-
culate or <(
caudate
to disto-
matous
smooth
lorn
L
h
(■ short,
ribbed { iong .
f short,
granulate j , _
globosa, Montagu; Williamson, Monogr. p. 8, pi. 1. figs. 15, 16.
. I avis, Montagu ; Williamson (A. vulgaris), Monogr. p. 3, pi. 1. fig. 5.
clavata, D’Orb. Eor. Poss. Yien. p. 21, pi. 1. figs. 2, 3.
semistriata, Williamson, Monogr. p. 6, pi. 1. figs. 7, 9.
striata, D’Orb. Eor. Amer. Mer. p. 21, pi. 5. fig. 12.
sulcata, Walker and Jacob ; Williamson (A. vulgaris, var. striata), Mo-
nogr. p. 6, pi. 1. fig. 10. [The typical Lagena.']
acuticosta, Eeuss, Sitz. Ak. Wiss. Wien, vol. xliv. p. 303, pi. 1. fig. 4.
Melo, D’Orh. For. Amer. Mer. p. 20, pi. 5. fig. 9.
Tiexagona, Williamson, Monogr. p. 13, pi. 1. fig. 32.
squamosa, Montagu; Williamson, Monogr. p. 29, pi. 1. fig. 29.
Tiispida, Eeuss, Sitz. Ak.Wiss.Wien, vol. xlv. p. 335, pi. 6. figs. 77-79.
aspera, Eeuss, Sitz. Ak. Wiss. Wien, vol. xliv. p. 305, pi. 1. fig. 5.
marginata, Montagu ; Williamson, Monogr. p. 10, pi. 1. figs. 19-21.
racliato-marginata, Parker and Jones (var. nov.), Plate XVIII. fig. 3.
squamoso-marginata, Parker and Jones(var. nov.), Plate XVIII. fig. 2,
trigono-marginata, Parker and Jones (var. nov.), Plate XVIII. fig. 1.
apiculata, Eeuss, Haid. ges. nat. Abhandl. vol. iv. p. 22, pi. 1. fig. 1 ;
and Sitz. Ak. Wiss. Wien, vol. xlvi. p. 318, pi. 1. figs. 4-8, 10, 11.
distoma-polita, Parker and Jones (var. nov.), Ann. Xat. Hist. 2 ser.
vol. xix. p. 279, pi. 11. fig. 23, Plate XVIII. fig. 8.
caudata, D’Orb. Eor. Amer. Med. p. 19, pi. 5. fig. 6.
distoma, Parker and Jones (var. nov.), Ann. Xat. Hist. ib. fig. 24.
distoma-aculeata, Parker and Jones (var. nov.), Plate XVIII. fig. 5.
distoma-margaritifera, Parker and Jones (var. nov.), Plate XVIII. fig. 6.
The family Lagenida (comprising Lagena , Nodosarina , Orthocerina, Polymorfhina , and
Tlvigerina) may be said to have its central home (bathymetrically speaking) at about
from 50 to 100 fathoms. Of these, Polymorphina is almost exceptional, however; for it
is, of this group, the most inclined to seek and flourish in shallow water, always avoiding
abyssal depths. Tlvigerina and Lagena are more capable even than Nodosarina of
living in deeper water than 100 fathoms, and of existing even at very great depths (2000
fathoms). Tlvigerina has its feeblest representatives in shallow water; but Lagena
attains as fair a size in shallow water as it does at 100 fathoms ; and at 1000 fathoms
it is often in good condition. Nodosarince are, as to their habitat, intermediate between
Polymorjphince and the others. They are of large size at 100 fathoms ; and are found
occasionally, but small a,nd rare, at 1000 fathoms; and in shallow water they are more
abundant than in the abyssal depths, and attain a larger size.
Lagena sulcata , Walker and Jacob, Var. ( Entosolenia ) globosa, Montagu. Plate XIII.
figs. 37 a, 37 b (Arctic) ; Plate XVI. figs. 10 a, 10 b (North Atlantic).
This is the simplest of the Lagence , subspherical and Entosolenian, that is, having an
intus-suscepted mouth-tube. It is entirely devoid of ornament, and generally thin-
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 349
walled. It may be said to be a feeble form connecting L. Icevis with swollen varieties
of L. marginata.
L. globosa comes from 30 to 40 fathoms, and from 60 to 70 fathoms at the Hunde
Islands (Dr. Sutherland) ; and in both dredgings it is rather common and of middling
size. Also from Baffin’s Bay, lat. 75° 10' N., long. 60° 12' W. (Parry) ; here it seems to
be rare, but is of large size, — a curious fact, in contrast with the occurrence of equally
large individuals of this variety at very great depths (1080 fathoms) in the tropical
Atlantic (lat. 2° 20' N., long. 28° 44' W.).
This also is a world-wide and very common Lageno , as we may see by Table VII.
Professor Reuss has it fossil from the Chalk of Maestricht and of Lemberg, from the
Septarian Clay of Pietzpuhl, the Salt-clay of Wieliczka, and the Crag of Antwerp
(Monogr. Lagen. p. 318). It is of good size and rather common in the English Crag
also.
L. globosa was figured and described by Walker and Boys, but not named by Walker
and Jacob in Kanmacher’s edition of Adam’s ‘Essays on the Microscope,’ where the
specific names given by Walker and Jacob are recorded. It was named by Montagu,
‘Test. Brit.’ p. 523.
Plate XYI. figs. 10 #, 10 b (North Atlantic).
Equivalent to fig. 37 of Plate XIII., but having more neck, and like figs. 30 & 31
(L. sulcata ) in outline and in thickness of neck.
Rare and large at 415 fathoms, lat. 52° 8', long. 12° 31', North Atlantic.
Lagena sulcata , Walker and Jacob, Var. Icevis *, Montagu. Plate XIII. fig. 22 (Arctic);
Plate XYI. fig. 9 a (North Atlantic).
Fig. 22 is the common, smooth, flask-shaped Lagena of authors. In this specimen
pseudopodial passages are crowded about the lower third of the shell, the upper two-
thirds being destitute of such foramina. We have observed that in Lagence such perfo-
rations occur only when the shell is of a certain thickness, considerable tracts of the
shell-wall being often extremely thin and imperforate. In the very small-ribbed varie-
ties (such as figs. 25-27) perforations are arranged in a row on each side of the costa,
where its base is thick ( L . striatopunctata). In the closely allied Entosolenian L. mar-
ginata also (as in fig. 44), perforations occur principally along the thickened margins,
occasionally as a broad band ; though sometimes (as in fig. 42) they are also scattered
sparsely over the whole shell.
This is from the mixed sands from Norway above alluded to. It is world-wide, often
found at considerable depths, but shallow water appears to be its favourite habitat. In
the fossil state this smooth variety is very abundant in the Post-pliocene clays of Lincoln-
* Taking this as the type of Lagena, Williamson thought that “ laevis ” was not an appropriate name for a
shell that is often ornamented, and substituted the term “ vulgaris” ; this unnecessary change has been unfor-
tunately adopted by Reuss (Sitzungsb. Ak. Wien, vol. xlvi. p. 321).
MDCCCLXV. 3 B
350
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
shire and Cambridgeshire, and in the Grignon sands (Eocene) ; it occurs also in the
Vienna Tertiaries, and (according to Reuss, Monogr. Lagen. p. 322) in the Crag of Ant-
werp, the Septarium-clay of Pietzpuhl, and the Tertiary beds of Taranto (Costa). It is
rare in the English Crag.
Plate XVI. fig. 9 a (North Atlantic).
This figure represents a specimen of L. Icevis from the North Atlantic, where this
variety is very rare and of middling size at 329 fathoms, lat. 49° 26', long. 49® 48', and
rare and large at 223 fathoms, lat. 52° 11', long. 13° 45'.
Lagena sulcata , Walker and Jacob, Var. semistriata , Williamson. Plate XIII. fig. 23
(Arctic).
This beautiful little Lagena connects the smooth with the striated varieties. Like the
others, it varies much in shape and in the strength of its riblets ; the specimen figured
by Professor Williamson (pi. 1. fig. 9) is much more decanter-shaped than ours, and has
a very long neck, with a neatly turned rim or lip ; our specimen is deficient as to this
latter character. We quite agree with Professor Reuss in grouping Williamson’s
L. vulgaris, var. perlucida (Monogr. p. 5, pi. 1. figs. 7, 8), with this variety. Montagu’s
L. perlucida is a six-ribbed L. sulcata. We found this specimen (fig. 23) in the shelly
sand from the Hunde Islands, Davis Straits, 50 to 70 fathoms. Dr. Wallich figures
L. semistriata in ‘The North -Atlantic Sea-bed,’ pi. 5. fig. 17.
It is very common to meet with Lagence, both recent and fossil, taking on striae and
riblets to greater or less extent, as in this instance. Reuss figures finely striated speci-
mens from the Crag of Antwerp in his paper on the Laqenidce, Sitzungsb. Wien Akad.
vol. xlvi. pi. 2. figs. 18-21.
Lagena sulcata. Walker and Jacob, Var. striatopunctata, nov. Plate XIII. figs. 25-27
(Arctic).
We have long known this variety from the Indian Ocean on Clam shell, and at
2200 fathoms, the Red Sea (372 fathoms), South Atlantic (2700 fathoms), and from
the Eocene deposits of Grignon, but it has not been hitherto figured nor described.
It is a relatively small Lagena, and is one of the most delicate. It varies in shape,
from forms more delicately elongate than the tear-shaped specimen represented by
fig. 25, to those having the usual flask-shape, with longer neck than in fig. 27. The
ribs are comparatively strong ; they range in number from four to twelve, and in one
recent specimen we have seen them spiral. The thickened base of the ribs is neatly
perforated on each side by pseudopodian foramina, which also occasionally pass through
the rib itself, from within outwards.
L. striatopunctata occurs rather common at the Hunde Islands, 30 to 40 fathoms,
in shelly sandy mud, and here attains a size greater than those in the Indian Ocean, or
those from the inside of a Grignon shell (p. 419, note); the specimens from the Red
Sea, however, are as large as those from Davis Straits.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 351
Lagena sulcata, Walker and Jacob. Plate XIII. figs. 24, 28-32 (Arctic) ; Plate XVI.
figs. 6, 7, 7 a (North Atlantic).
This is the typical form of Lagena ; its variations lead, in one direction, into the
feebler forms (L. semistriata, Icevis , globosa ) ; on the other hand, we have varieties with
reticulated, hispid, and granular ornament; and there are also compressed forms, and
elongate varieties, departing more or less widely from the middle type presented by
the ovate and characteristically costate Lagence.
Figs. 30 & 31 represent the best characterized forms (though not absolutely the
largest) that we know of in the group of Lagence. This is shown in their boldness of
growth, the strength of their ribs (twelve to fourteen in number), and particularly in
the radiated structure of the aperture. This last seems to be a rare condition ; we have
as yet seen it only in these specimens *, but it is one among many features showing the
intimate relationship between Lagena, Nodosarina, and Polymorphina.
L. sulcata of Walker and Jacob, in Kanmacher’s edition of Adam's 4 Essays,’ well-
figured previously by Walker and Boys, is a good-conditioned, strongly ribbed, and
flask-shaped shell; our figs. 28-31 present less neck; but Williamson’s figure oiL. vul-
garis, var. striata (Monogr. p. 6, pi. 1. fig. 10), and Reuss’s figure of his L. Jilicosta
(Monogr. pi. 4. figs. 50, 51), show as much or more neck and a better lip than Walker’s
figure does ; but they are rather less globose, passing off into L. Amphora, Reuss, and
L. gracilis, Williamson. See Reuss’s Monogr. Lagen. pi. 4, where by extreme care the
ovate, flask-like, and fusiform shapes of the well-ribbed L. sulcata are divided into seven
44 species,” according to their gradations of shape and modifications of ornament. It is,
however, next to impossible, and of very little use, to institute minor distinctions with
these Lagence.
As explained in the Annals Nat. Hist. 1859, 3 ser. vol. iv. p. 336, Montagu termed
this form 44 striata,” overlooking the prior name, which alone is necessary.
Figs. 28 & 29 are from the Hunde Islands, 30-70 fathoms; and from the Arctic
Ocean (found in the mixed sands).
Figs. 30 & 31 represent specimens from the Hunde Islands also, three gatherings by
Dr. P. C. Sutherland, in shelly sandy muds, from 30-70 fathoms; within this limit
L. sulcata is most common ; and is largest at the greater depth. Perhaps the figured,
specimens nearest to these are L. Isabella and L. raricosta, D’Orb., from the Falkland
Islands (Foram. Amer. Merid. p. 20, pi. 5. figs. 7, 8, 10, 11). The almost exact coun-
terpart of these fine large specimens we have found in the Upper Chalk of Maastricht,
in the Crag of Suffolk, and in recent shelly sands from the Isle of Man. Reuss figures
(under other names) long- and short-necked specimens, strongly ribbed, of L. sulcata
from the Black Crag of Antwerp, and the Septarian Clay of Pietzpuhl and Herms-
dorf.
Among the localities given by Williamson for the common L. sulcata (Monogr. p. 6)
Professor Reuss figures this feature in some of the illustrations of his paper on the Lagenidce, Sitzungsb,
Ak. Wiss. Wien, Math.-Nat. Cl. vol. xlvi. 1862, Erste Abth. p. 308, &c. pi. 1-7.
3 b 2
852
ME. W. K. PAEKEE AND PEOPESSOE T. E. JONES ON SOME
we find the Hunde and Beechey Islands; Petersburg, U.S. (fossil; Miocene); and
English Crag.
This Lagena does not usually occur of so large a size as some of those from Hunde
Islands. The most common condition is represented by figs. 28 & 29. These are
smaller forms wanting the radiate structure of the aperture, but not separable from the
type. Fig. 82 is a similar, but still smaller, form, and rather distorted. These feebler
varieties of L. sulcata are common in all seas wherever Lagence are found.
Plate XIII. fig. 24 is a rather small flask-shaped Lagena with costulse, having a spiral
twist, which are intermediate in strength between the delicate riblets of fig. 23 and
the strong ribs of the type-form, L. sulcata. The spiral arrangement of the costulse is
very variable in different individuals collected from various places : the obliquity and
curvature of these ornaments being greater or less; and, as usual, the riblets vary
in length, even in the same individual, being sometimes short, and sometimes
lengthened so as to creep upwards, twining round the neck as far as the mouth. The
intervals or flutings (sulci) may have a width equal to, or be far greater than, the
ridges or riblets. When very small the riblets have been mistaken for minute sulci or
“ striae.” With regard to the rib-ornament of Lagena , we may observe that the costa-
tion of the flatter varieties is sometimes reduced to a mere keel (as in the Cristellarian
forms of Nodosarina ) ; either as a single keel ; or a larger marginal, and a secondary,
pair ; thus making six costae crowded at the edge (as in Lagence common in the Ter-
tiary beds of Grignon). A somewhat similar condensing of the ordinary riblets into a
few (six and even three) large ribs takes place in the cylindrical Nodosarice. In one
form of Lagena from the Grignon beds, we have three, meridional, three-edged, equal
ribs ( L . trigono-marginata , Parker and Jones, Plate XVIII. fig. 1) ; and in another four,
strong, equal, spiral ribs (marked by pseudopodia, as in L. striatopunctata ), this is our
L. tetragona, Plate XVIII. fig. 14.
Fig. 24 is one of the feeble forms of L. sulcata (type), world-wide, and acclimatized
to nearly all latitudes and depths ; it is common at Hunde Islands (Dr. Sutherland), at
CO -70 fathoms in shelly sandy mud.
Plate XVI. figs. 6, 7, 7 a [including Var. caudata , D’Orb.] (North Atlantic).
Various modifications of the typical Lagena , from the North Atlantic, are shown by
figs. 6, 7 «, 7 b. Fig. 6 is like fig. 29 of Plate XIII., but it is rather more globose, has
rather shorter ribs, and is apiculate (non-essential differences, though the last feature
makes it Var. caudata , D’Orb.). Fig. 7 a is smaller and less globular than figs. 30 & 31
of Plate XIII.
These are rare and of middling size at 2330 fathoms, lat. 50° 25', long. 44° 19', North
Atlantic; rare and small at 223 fathoms, lat. 52° 11', long. 13° 45' ; and rather common
but small at 43 fathoms, lat. 51° 57', long. 10° 30'.
Fig. 7 b (Var. caudata , D’Orb.) has an elongate olive-like shape, and thinner costae than
the others. It was rare and of middle size at 1450 fathoms, lat. 50° 6', long. 45° 45' ; and
rare and small at 2350 fathoms, lat. 51° 29', long. 38° 1', North Atlantic.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
358
Lagena sulcata , Walker and Jacob, Yar. (Entosolenia) Melo, D’Orb. Plate XIII. figs.
33-36 (Arctic).
This is L. sulcata with a modified ornamentation. It has small transverse ridges
between the ribs, connecting them, and forming subquadrate reticulations, which vary
in different specimens.
Professor Reuss would retain Williamson’s term catenulata for those specimens that
have the cross-bars weaker than the ridges; probably a convenient, though hardly
necessary, arrangement ; the modifications of the relative thicknesses of the longitudinal
and transverse ridges are endless, varying from a network of thin lines, equal or unequal
in strength, to that with broad, flat, equal ridges, and shallow squarish pits between.
Further, our figs. 33-36, Plate XIII., show sufficiently clearly that no characteristic can
be found in the disposition of the secondary or transverse riblets, whether end to end,
or alternately between contiguous ribs ; for in the same specimen they vary as regards
this arrangement.
Fig. 34 has but few of the cross-bars, and these are oblique. In this it not only con-
nects L. sulcata with L. Melo by the presence of secondary riblets, but the obliquity of
these connecting bars shows a tendency towards the formation of the variety L. squamosa ,
next to be described, in which the ornament has a honeycomb- rather than a ladder-
pattern. Dr. Wallich figures another pretty passage-form, ‘ North- Atlantic Sea-bed,’
pi. 5. fig. 23.
Figs. 33 & 35 differ in the relative size of the areolse ; a condition dependent upon
the number of the primary ribs, and very variable. From the Hunde Islands, 30-70
fathoms; and from the Arctic Ocean (mixed sands).
Fig. 36 is an extremely rare monstrosity, being a Lagena with a superadded chamber.
It is from the Hunde Islands, from between 30 and 40 fathoms, shelly muddy sand
(Dr. P. C. Sutherland). This specimen is unique in our collection. Soldani has
figured a specimen extremely like this one, in his ‘ Testaceograph.’ vol. i. part 2, pi. 95.
fig. A ; named Nodosaria cancellata by D’Orbigny (Ann. Sc. Nat. vol. vii. p. 254, No. 29).
As a rule, monstrosities of the Lagena are formed by the budding, as it were, of a
new chamber obliquely on the side of the original chamber (Plate XVIII. figs. 10-12);
these are very rare. If, however, a smooth or ribbed Lagena were to take on an addi-
tional chamber in the axis of the primary chamber, it would be scarcely distinguishable
from a Nodosaria. We possess such a form (from the shallow water at Eastbourne),
Plate XVIII. fig. 9, which we believe to be a monster of Lagena Icevis. In the Tertiary
Sands of Bordeaux also, rich with Lagence and small Nodosarice , very puzzling forms
occur, which may either be two-celled individuals of Nodosaria scalaris, Batsch *, or
possibly monstrous varieties of Lagena sulcata. In the specimen before us (Plate XIII.
fig. 36) we have a mode of ornamentation never found in any Nodosarian Foraminifer;
* Well figured by Wallich in ‘ The North- Atlantic Sea-bed,’ pi. 5. fig. 18, and in Journ. Sci. No. 1, Jan. 1864,
fig. 6, in the plate illustrating his paper on the bed of the Atlantic Ocean. Figured also, for comparison, in
our Plate XVIII. fig. 13.
354
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
and therefore, whilst we have some doubt as to the two-celled forms that have either no
surface-ornament, or a sculpturing common to Nodosaria and Lagena , here we have
satisfactory means of diagnosis.
Everywhere in the Foraminiferal group, we have most curious instances of Isomor-
phism, not merely between nearly related species, but between even the diverse forms of
separate families (as between those of the Vitreous and Porcellanous Series). In the
case under notice isomorphism may be said to occur between three closely cognate
specific groups : thus, the specimen of Lagena before us has imitated a Nodosaria ; whilst
those already spoken of as taking on a second chamber obliquely have the habit of a
young Polymorphina (see fig. 46).
Lagena Melo is not uncommon in company with other Lagence , though not so com-
mon as the smooth, sulcate, honeycombed, and marginate varieties. For its occurrence
(recent and fossil) in the Mediterranean Area, see Quart. Journ. Geol. Soc. vol. xvi.
Table, p. 302.
Lagena sulcata , Walker and Jacob, Var. (Entosolenia) squamosa, Montagu, sp. Plate
XIII. figs. 40, 41 (Arctic) ; Plate XVI. figs. 11 a, 11 b (North Atlantic).
This represents a state of ornamentation peculiar to the Lagence amongst the “ hyaline,”
and to certain varieties of Miliola Seminulum among the “porcellanous ” Foraminifera.
In L. Melo the cross-bars are often weaker than the longitudinal ribs, and pass straight
across from rib to rib, like the secondary veins in a monocotyledonous leaf, such as
Alisma, Myrsiphyllum, &c. In L. squamosa, however, not only have the secondary rib-
lets become equal to the primary, but, by the zigzag inflection of the latter, a nearly
regular hexagonally areolated ornament is produced, reminding one strongly of the
polygonal meshes produced by the more perfect reticulation of the woody tubes in a
dicotyledonous leaf. Early observers, using but imperfect microscopes, compared this
retose ornament with a scaly skin of a fish (see Williamson, Monograph, p. 12).
In fig. 34 we have noticed a variety of L. sulcata in which a few secondary bands had
united with the main ribs, commencing, as it were, the honeycomb-pattern.
Fig. 40, the largest of our specimens, is from the Hunde Islands* (Dr. P. C. Suther-
land), 50 to 70 fathoms ; and the smaller one from the Arctic Ocean (MacAndrew and
Barrett).
L. squamosa is of world-wide occurrence ; but, like L. Melo, is not so abundant as the
long flask-shaped and the marginated forms. Reuss has it from the Black Crag of
Antwerp, and we have it fossil from Castel Arquato. By far the bulkiest specimens of
L. squamosa that we have seen are from a Tertiary sand, which, rich in many varieties
of Lagence , in Ovulites, Polymorphina, and Vertebralina, was taken from the inside of a
Cerithium giganteum from Grignon (page 419, note).
In this reticulate Lagena the neck is usually intussuscepted (Entosolenian) ; in the
large fossil form ( L . tubifero-squamosa, Parker and Jones, Plate XVIII. fig. 7), however,
* Professor Williamson has also noted its occurrence here (Monogr. p. 12).
EORAMINIEERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 355
the neck is protruded in some cases to a considerable extent, and has about three
secondary tubular apertures arising from it laterally, and almost at right angles to the
main tube. This is an isomorphism with Polymorpliina tubulosa, and with certain feeble
bifurcating forms of Nodosaria from Cretaceous beds.
Plate XVI. figs. 11 a, 11 b (North Atlantic).
The specimen here figured is a little less globular than figs. 40, 41 of Plate XIII.,
and has its reticulation rather more regular. Rare and middle-sized at 1450 fathoms,
lat. 50° 6', long. 45° 45', North Atlantic. In Dr. Wallich’s ‘ North- Atlantic Sea-bed,”
pi. 5. fig. 21 seems to be L. squamosa.
Fig. 11 a, Plate XVI. has the six-sided meshes one above the other, touching by the
parallel sides of the hexagon, and in so much corresponding with Williamson’s L. sca-
lariformis (Monogr. p. 13. pi. 1. fig. 30), and Reuss’s L. geometrica (Monogr. Lag. p. 334,
pi. 5. fig. 74) ; but this straight meridional arrangement of the meshes is lost in the less
regular reticulation of such specimens as figs. 40 & 41 in Plate XIII., where square,
six-sided, and irregular meshes occur, in straight, oblique, and irregular lines. Professor
Reuss’s unnecessary disuse of Montagu’s term squamosa for this varietal group leads to
increased confusion in any attempt to subdivide these reticulate Lagence , which have no
natural divisions among themselves.
Lagena sulcata , Walker and Jacob, Var. ( JEntosolenia ) marginata, Montagu. Plate XIII.
figs. 42-44 (Arctic); Plate XVI. figs. 12 a, 12 b (North Atlantic).
These are flattened forms variable in shape ; generally Entosolenian, but sometimes
Ectosolenian with a long delicate neck. This compressed shape is usually associated with
a trenchant margin, sometimes slightly apiculated (as in fig. 42), and sometimes dentate
or rowelled (as in Williamson’s Monograph, pi. 1, figs. 21 a , 25, 26), reminding one of
the keel of certain Cristellarice. Occasionally in large well-developed specimens of L.
marginata (recent and fossil) the margin is composed of a large predominant rib,
strengthened by a pair of smaller costae ; showing that, as in other Foraminifera, espe-
cially the Nodosarine group, the exogenous costae gather themselves to the margins, the
rest of the surface becoming less and less ornamented. The pseudopodial pores also
usually affect the neighbourhood of the thickened margin in these flattened forms, just
as they follow the ridges of L. striatopunctata (figs. 25-27). Occasionally the pseudo-
podia have perforated the whole surface, either sparsely, as in fig. 42 a, or freely, as we
have seen in specimens from the Indian Sea.
In some rare specimens from the Coral-reefs of Australia, and fossil at Bordeaux, we
see the pseudopodia begin to enter the shell-wall near the centre, and then burrow
radially to escape near the margin; the shell-surface being perfectly smooth and as
polished as glass. This is our subvariety Lagena radiato-marginata, Plate XVIII. fig. 3.
In the Crag of Suffolk there is another subvariety of L. marginata , in which the radiating
canals are visible only at the margin.
The intussuscepted neck-tube in L. marginata is generally more or less oblique, some-
356
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
what trumpet-shaped, and of varying length (as may be seen in figs. 42 & 43). Fig.
44 has the tube partly protruded, and partly internal. The apparent difference in the
setting on of the mouth, which we formerly thought we could detect, between Entoso-
lenia and Lagena proper (Annals Nat. Hist. 2 ser. vol. xix. p. 279), does not really exist,
for we find that in any of the subspecific groups forms may occur having either a gently
tapering neck (Ectosolenian), or a tube abruptly set in (Ento-ecto-solenian), or a mouth-
tube entirely intussuscepted (Entosolenian). L. marginata is sometimes distomatous,
being open at the base, and then coming under another (artificial) subdivision.
Between such globose forms as figs. 38 & 39, and the flattened ones (figs. 42-44),
there is an almost infinite number of gentle gradations shown in specimens from all
parts of the world.
The specimens figs. 42-44 occur at the Hunde Islands (Dr. Sutherland), in three
dredgings at from 30 to 70 fathoms, and at Drontheim, North Cape (MacAndrew and
Barrett), from 30 to 200 fathoms. Rather common. Professor Williamson has already
recorded the occurrence of L. marginata at 100 fathoms at the Hunde Islands (Monogr.
pp. 10 & 11). Like other Lagence , it is world-wide ; and is abundant in the Tertiaries :
it is rather common, for instance, in the Crag of Suffolk. For some of its Mediterranean
habitats (recent and fossil) see Quart. Journ. Geol. Soc. vol. xvi. p. 302, Table. Under
the name of Oolina compressa , D’Orbigny described it as occurring with other Lagence at
the Falkland Isles. It is figured by J. D. Macdonald, Assist.-Surgeon H. M. S. Herald,
in the Annals Nat. Hist. 2 ser. vol. xx. pi. 5. figs. 7-10, but not described. He found it,
together with a dimorphous TJvigerina (with loosely set, straggling chambers), Spirolo-
culina planulata , Quinqueloculina Seminulum, and Triloculina oblonga in 440 fathoms
water between Ngau and Viti-Laru, in the Feejee group of islands.
L. marginata is sometimes hexagonally areolated, like L. squamosa , but more feebly
( L . squamoso-marginata, Parker and Jones, Plate XVIII. fig. 2) ; as we have seen in
specimens from the Tertiary beds of San Domingo, and from the white mud of the
Australian Coral-reefs.
Plate XVI. figs. 12 a, 12 b (North Atlantic).
Here we have a slight modification in the development of the keel, as compared with
the equivalent specimens represented by figs. 42, 43, Plate XIII. In the North Atlantic
L. marginata is rare and small at 740 fathoms; rare and middle-sized at 1450 fathoms;
rather common and large at 2350 fathoms; rare and large at 415 fathoms; rather common
and small at 90 fathoms; and common and small at 78 and 43 fathoms. Dr. Wallich
figures three forms of L. marginata , ‘ North- Atlantic Sea-bed,’ pi. 5. figs. 19, 20, 22.
Lagena sulcata , Walker and Jacob, Var. distoma , nov. Plate XIII. fig. 20 (Arctic).
Fig. 20 represents a long, costulated, fusiform Lagena , open at both ends, with one
extremity rather more tapering than the other. This variety of Lagena has not been
previously named. It was figured and described by us in the ‘ Annals Nat. Hist.’ ser. 2.
xix. p. 279, pi. 11. f. 24. See also Trans. Linn. Soc. xxiv. p. 467, pi. 48, f. 6, Brady.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 357
It can only be received as a varietal form of the typical Lagena sulcata , Walker and
Jacob ; but, like other noticeable varieties of Foraminifera, it requires a distinctive
binomial appellation. It is from Norway (MacAndrew and Barrett) ; found in mixed
sands and muds dredged at various places between Drontheim and North Cape, and at
depths varying from 30 to 200 fathoms ; of rare occurrence. It is very rare in deep
water off Shetland, and not uncommon off the Northumberland coast (H. B. Brady).
The exact counterpart in form, but somewhat of less size, occurs in the clay beneath
the fen near Peterborough, but not in any abundance. A somewhat similar, large, two-
mouthed Lagena is found in the Sponge-sand from Melbourne, Australia, and is rather
common: it is even larger than our Arctic specimens; is never quite straight; and,
instead of being covered with delicate costulee, is richly ornamented with pearl-like
grains, profusely spread over the surface, hence we call it Lagena distoma-margaritifera ,
Plate XVIII. fig. 6.
A smooth distomatous Lagena , of twice the size of the last mentioned, is not
uncommon in the rich fossil Rhizopodal fauna so well worked out of the Crag of Sutton,
Suffolk, by Mr. S. V. Wood, F.G.S. This Lagena of the Crag of Suffolk is the largest
of the elongate Lagence that we know.
Dr. Carpenter supposes that the elongate distomatous Lagence may be double La-
gence joined by their bases (Introd. p. 157); and Professor A. E. Reuss suggests that they
are separated chambers of Nodosarice or Lentalinoe (Sitzung. Ak.Wien, vol. xlvi. p. 315);
but in these opinions we can by no means agree. Our L. distoma is grouped by Reuss
( loc . cit. p. 331) with L. gracilis , Williamson ; but our description and figure show the
distinctive features.
Lagena sulcata , Walker and Jacob, Var. distorna-jjolita, nov. Plate XIII. fig. 21 (Arctic).
Another elongate, fusiform, distomatous variety of Lagena (fig. 21), but smooth instead
of costulate, occurs in the same Norway dredgings, and in the Red Sea (Pullen’s sound-
ings), on the beach near Melbourne, at Swan River, on the Australian Coral-reefs, and
on the Durham Coast (Brady), and of a large size (relatively) in the Crag of Suffolk.
As fig. 20 represents a distomatous, striated, subcylindrical variety of L. sulcata , so
fig. 21 is a smaller and smooth distomatous, but amphora-shaped, variety ; the former
may be said to be, in one sense, a subvariety of L. striata , and the latter a subvariety
of L. laevis. In the Norway dredgings it is smaller and rarer than L. distoma (fig. 20).
Its two extremities are not nearly so equal as those of fig. 20, and the shell is not so
cylindrical ; but in the hotter seas it is long and slender (Plate XVIII. fig. 8). W e
term it L. distoma-polita. In some respects it has less departed, than L. distoma has,
from the ordinary smooth flask-like forms, especially those which are somewhat pointed
at the bulbous end, as Lagena apiculata, Reuss (Sitzungs. Akad. Wien, vol. xlvi. p. 1,
figs. 4-8, 10, 11). In fact the subdivision of these varieties is artificial, and made only
for the sake of convenience.
3 c
MDCCCLXV.
358
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Lagena sulcata , Walker and Jacob, Var. ( JEntosolenia ) apiculata, Reuss, et caudata ,
D’Orbigny. Plate XIII. figs. 38, 39 (Arctic) ; Plate XVI. figs. 6, 7, 8, 9 (North
Atlantic).
The distomatous condition of Lagena also obtains in the globular forms (included in
the Oolince of D’Orbigny), which frequently have the neck-tube lengthened inwards and
free (the characteristic of JEntosolenia, Ehrenberg), see figs. 38 & 39. Among these the
base of the shell is frequently drawn out or apiculate (as in fig. 39, and in the figures of
L. apiculata, Reuss, above mentioned), and sometimes perforate, as it is in fig. 38.
This also holds good in the compressed varieties ( L . marginata). Also among the flask-
like Lagence we have apiculate forms, as in Oolina (Amphorina) caudata , D’Orb., whether
striated, as that is, or smooth ; such also are L. apiculata , Reuss, L. globosa , var. lineata ,
Williamson (Monogr. pi. 1. fig. 17), L. strumosa, Reuss, L. mucronata, Reuss, &c. Any
of these may be perforate. See also Plate XVI. figs. 6, 7, 8, 9.
Excepting, then, that the globular and lenticular Lagence are frequently Entosolenian,
none of these characters, whether of elongation, apiculation, and perforation, or of being
smooth, striated, sulcated, honeycombed, or reticulate (as we shall see with the orna-
mented forms), are confined to one or another set of Lagence. No specific distinctions
can be based on any of these features ; but, for convenience sake (as among other spe-
cies of Foraminifera), several subspecies and varieties take binomial appellations. To
avoid, however, too great an accumulation of such names we must adopt the published
names whenever it is possible ; and in this case D’Orbigny’s Oolina caudata will serve
as a point around which the apiculate and distomatous Lagence , of the flask-shaped and
more or less globular varieties, may be conveniently grouped. The large sub cylindrical
and fusiform specimens, like a little rolling-pin in shape, well represented by fig. 20,
will stand as a distinct variety.
Fig. 38 (Plate XIII.) differs from L. globosa (fig. 37) in being more elongate or olive-
shaped, and in having a subsidiary tubular aperture at its base. Fig. 39 has also the
fundus drawn out or apiculate, but not pervious. A large number of these apiculated
forms, varying much in outline and in ornament, sometimes distomatous (as fig. 38),
are not at all uncommon, and may be grouped under the name “ caudata ” given by
D’Orbigny to one of his Oolince. Sometimes they are Entosolenian (as is seen in
fig. 39 a), and often they are Ectosolenian, as in D’Orbigny’s 0. caudata , Foram. de
l’Amer. Merid. pi. 5. fig. 6, a striated form. Compare also the smooth, amphora-
shaped, distomatous Lagena , fig. 21, above described.
From 30 to- 40 fathoms at the Hunde Islands (Dr. P. C. Sutherland) ; not common,
small. World- wide. Fossil in the Tertiary formations.
Plate XVI. figs. 6, 7, 8, 9 (North Atlantic).
Allied closely to fig. 21 of Plate XIII., but more swollen ; fig. 8 being more lanceolate
in outline, and fig. 9 more flask-like, than fig. 21 ; whilst figs. 6 & 7 are striated also.
These are rare and small at abyssal depths in the North Atlantic.
A very interesting group of ten Lagence from the Falkland Isles was figured and
EOEAMINIFEEA EEOM THE NOETH ATLANTIC AND AECTIC OCEANS.
359
described (as Oolince ) by D’Orbigny in his work on the Foraminifera of South America
(Voyage dans l’Amer. Merid. partie 5me, 1839, p. 20). These represent most of the
modifications shown among the Arctic and North Atlantic forms. Thus
Oolina inornata, op. cit. pi. 5. fig. 13 = Lagena globosa, Montagu.
lasvigata, ,,
fig. 3 = L. lee vis, Montagu.
striatocollis, „
fig. 14 = L. semistriata, Williamson.
striata, „
fig. 12
Vilardeboana, „
figs. 4, 5 s
Isabella, „
figs. 7, 8 ' = L. sulcata, Walker and Jacob.
rarieosta, ,,
figs. 10, 11 J
Melo, „
fig. 9
compressa, „
figs. 1, 2 = L. marginata, Montagu.
caudata, „
fig. 6
Genus Polymorphina.
Polymorphina lactea , Walker and Jacob, sp. Plate XIII. figs. 45, 46 (Arctic).
Of the hyaline Foraminifera, Polymorphina alone forms itself persistently of a double
row of alternating opposite chambers ; except very rarely, when its latest chambers are
uniserial ( Pimorphina ). TJvigerina (a closely related form) has normally three chambers
in one turn of the spire, forming a triple series of alternating chambers. Teoctularia
has normally a double series of chambers alternating with each other, much as in Poly-
morphina, but more regular in arrangement, and having a far more gradual increase of
size. Textularia, however, often begins with a triserial (Verneuiline) arrangement, such
as is normal in TJvigerina ; and, like the latter, it often finishes its shell with a single
row of chambers ( Bigenerina ).
In Polymorpliina , although the arrangement of the chambers is essentially biserial,
yet they are very apt to grow so loosely that a cross section through the shell will often
expose three or more chambers.
This shell is normally drop-shaped, tear-shaped, and pyriform ; it may, however,
become flattened out into the proportions of the thick leaf of a succulent plant, or be
elongated into an irregular oblong, somewhat like a wheat-ear or grass-spike. These
longer forms (such as fig. 48) are isomorphic with Textularia proper. Of its Dimor-
phine condition there are Nodosarian, Textularian, and Uvigerine isomorphs.
The aperture of Polymorphina agrees with that of the Nodosarince , and of the well-
grown Lagence (such as figs. 30 & 31), being radiated or plicated, the sarcode passing
through a circular series of slits. The actual centre of the aperture is sometimes filled
up with a bead of calcareous matter (fig. 52 h), and this occurs in Nodosarince also.
W e have seen above that the varieties of Lagence are almost equally divided among
those which have a gently graduating external neck, those having an entirely internal
neck-tube, and those in which the tube is partly extruded and partly internal. In Poly-
morphina also this may be said to hold good to some extent ; for in small and in young
specimens (fig. 46) we see the Entosolenian tube, just as in the globular and flat Lagence
3 c 2
360
MR. W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
(figs. 39, 42, 43). Indeed in specimens having five chambers we have distinguished a
tube in each chamber. In large individuals the apertural plicae grow quite as far into
the chamber as they project outwards. Thus the Entosolenian character of aperture is
generally present ; and though the mouth does not pout so much as in many of the
Nodosarite and Lagence, yet the last chamber not unfrequently sends out a dendritic
growth of exserted apertural tubes — a character noticed by us in a large Lagena also
common in the Tertiary beds of Grignon (see p. 354). Nor is this feature unrepresented
among the Nodosarice , as shown by the dichotomous Dentalina aculeata , D’Orb., of the
Chalk and Gault.
The shell of Polymorphina has usually a glassy smoothness ; it rarely shows any ten-
dency to striation ; when this occurs, it is longitudinal, but feeble, and then arises from,
apparently, the fusion of granules arranged in rows ; whereas in the three most cognate
species ( Nodosarina , Lagena , and Uvigerina ) striation and strong costation of the cham-
ber-walls are extremely common. It has, however, at times another mode of ornament,
such as is not unfrequently met with in the Nodosarine and Uvigerine groups, and
especially in the Globigerince of the deep seas in low latitudes, and in Calcarina , —
namely, prickles or long needles of shell-substance bristling over the surface. Another
surface-ornament is common in large well-grown Polymorphince , especially those of the
Crag of Suffolk (Mr. S. V. Wood’s Collection), which have a rich granulation of clear,
polished, calcareous beads and lobules scattered over the whole surface, but most
strongly on the older chamber-walls. A like granular ornament is common in the very
large distomatous Lagenas from the Australian shores (as already mentioned). The best
example of the development of this particular ornament is seen in the great explanate
Cristellarice of the Tertiary beds of Malaga, Sienna, and Turin.
In the form before us (figs. 45 & 46) we have a subglobular condition of P. lactea ,
Walker and Jacob. Fig. 46 is the young, showing, by transparency, the long Entoso-
lenian neck, as well as the radiated aperture. It has but two chambers, the second of
which is relatively small; in after-growth the chambers increase in size rapidly but
irregularly, and overlap each other in proportion to the gibbosity of the shell. We
possess complanate or leaf-shaped forms, such as are figured by D’Orbignt in his
For. Foss. Vienne, pi. 13. figs. 25-30, in which there is scarcely the least overlapping
of the chambers.
The two chambers of fig. 46 are the “primordial” and “ circumambient” chambers of
other polythalamous Foraminifera. We have seen a similar double-celled condition of
shell belonging to young forms within the chambers of the mother-shell, in Truncatulina
lolatula (from south coast of England), Peneroplis pertusus (from India), and in large
Orbitolites complanatus (from Fiji). In the last (some specimens of which were full an
inch in diameter) we found the mother-chambers, towards the periphery of the shell,
crowded with young ones*.
* These specimens, both old and young, may be seen in the Hunterian Museum, Royal College of Surgeons
(See Catal. Mus. Plants and Invertebr. 1860, p. 96, No. A 54) ; and have been described by Dr. Carpenter,
Introd. Foram., Ray Soc. p. 38.
EORAMINIFERA PROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
361
To us it appears that the Polythalamous Foraminifera are often, if not generally, vivi-
parous, and that the young shell, when hatched, consists of two chambers. We think
that the subsequent chambers of these Polythalamians are not always formed slowly,
one by one, but sometimes, at least, laid down, and marked off by the growth of two or
more septa, at the same time; calcification beginning at points nearest to the earlier
chambers, the thickness of the chamber-wall being in direct ratio with its age. This
mode of growth of more than one chamber at a time seems to be proved by the curious
manner in which the sarcode passes, by many bundles, from the older chambers into
the newest in those individuals of Polymorphina lacteco which throw out tubular stag-
horn processes from their last chamber (P. tuhulosci , D’Orb.); for, as may be seen in fig. 52,
the newest chamber, namely, that which bears the cervicorn appendage, communicates,
not merely with the ante-penultimate chamber, but, by a double row of lateral apertures,
with all the chambers occurring on its own side, namely those which it overlaps. The
communication of the last, outer, wild-growing chamber with the penultimate is not
only by means of this double row of apertures, but (as is seen in fig. 52 b) by the ordi-
nary radiated mouth. Another view, however, may be taken of the growth of such an
individual as fig. 52 : thus, we may suppose that absorption has taken place, opening
foraminal communications between the last and the former chambers. Either hypo-
thesis would explain the fact, — that, as we find on breaking open very large specimens
of the normal P. lactea , the stolon-passages between the older chambers are very free and
patulous ; whereas the terminal mouth of the last chamber presents the radiate condi-
tion; the only passage here for the sarcode being the thin slits around the strong
growth of hyaline shelly matter in the mouth.
Fig. 45 represents the group of individuals to which D’Orbigny applied the sub-
generic term Globulinci ; but neither this term nor that of Guttulina (another so-called
subgenus) can be separated from the ordinary, more or less oval, more or less pyriform,
or more or less elongate varieties of Polymorphina lactea.
Figs. 45 & 46 are from the Hunde Islands (Dr. Sutherland), in three dredgings from
25-70 fathoms. Rather common and of small size. Also from the Norway coast
(Mac Andrew and Barrett) in the mixed sands.
Polymorphina lactea , Walker and Jacob, Yar. compressa, D’Orbig. Plate XIII. figs.
47-51 (Arctic).
These are more or less flattened forms, ranging themselves around P. compressa , D’Orb.
(For. Foss. Vien. pi. 12. figs. 32-34), though not exactly identical with that variety of
P. lactea. In the relative length of the chambers, their setting on, and in the degree
of exposure of the plaiting by the alternation of the double series of chambers, these
Po lymorp bin m are so very variable, that we have taken the flattened condition as a
characteristic, and out of the very many names they have received, we have chosen
“ P. compressa ” as a secondary centre around which to collect a certain series of more
or less elongate and compressed forms, more elongate than P. lactea proper, and less
362
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
compressed than P. complanata, D’Orb. (For. Foss. Vien. pi. 13. figs. 25-30); the
latter being the centre of the group of leaf-like forms.
Fig. 47, though not so flat as D’Orbigny’s figure of P. compressa, comes nearest to it,
of these before us. Fig. 48, somewhat Textularian in its make, connects P. compressa
with D’Orbigny’s P. Thouini (Modele, 23): the latter, however, is still more elongate
and less compressed. In the Crag of Suffolk this elongation advances to such an extent
that the shell at first sight looks like a Dentalina : it has become the isomorph of the
elongate Virguline Bulimvna of the English Gault and the German Planer-Mergel.
Figs. 49 & 51 connect P. compressa with D’Oebigny’s P. Problema (Modele, 61). Fig. 50,
composed of about three chambers, is a young or an arrested individual of the com-
pressed type.
At the Hunde Islands, 30-40 fathoms, these forms of P. compressa occur rare and
small. From the Norwegian coast we have them, rather common and small, in the
mixed sands.
These are amongst the commonest forms of Polymorphina from the Lower Secondary
period up to the Recent.
Polymorphina lactea, Walker and Jacob, Var. tubulosa , D’Orbigny. Plate XIII. fig. 52 a-d
(Arctic).
This condition of P. lactea we have already spoken of. We may add that the tubular
appendages are found on Polymorphinae of various shapes, but generally on the more or
less spheroidal, or at least ovoidal, forms ; and it is only for the sake of convenience
that it can be regarded as a subcentral group and distinguished by a binomial appella-
tion. D’Orbigny’s figured and named specimen (For. Foss. Vien. pi. 13. figs. 15, 16)
has priority among several.
Fig. 52 a-c is from Bred Sound, Finmark (MacAndrew and Barrett), 30 fathoms.
The fragment fig. 54 d is from some other part of the Norwegian coast.
Tubulose individuals of P. lactea occur common in the Cretaceous deposits ; are very
common in some of the Grignon and other Tertiary beds ; and are very large in the Crag
of Suffolk (Mr. S. V. Wood’s Collection). In the Australian coast-sand (Melbourne)
living individuals of large size are abundant; and fine specimens live in the Bay of
Biscay (50-60 fathoms) and in the English Channel. One large and interesting speci-
men that we have obtained in the shelly sand off Plymouth is adherent to a fragment
of a bivalve shell ; its tubular arms spreading radially on the shell, like the wild-growing
cells of a Planorbulina or of a Carpenteria. Professor Williamson figures a fine tubu-
lose British Polymorphina (P. lactea , var. jistulosa , Monogr. fig. 150), and also a small
plano-convex, crenately winged form (P. lactea , var. concava , fig. 151), which he regards
(with much probability) as having been parasitic. We have met with similar forms in
sands of shallow waters.
EORAMINIEERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 363
Genus Uvigerina.
Uvigerina pygmcea , D’Orbigny. Plate XIII. figs. 53-57 (Arctic) ; Plate XVII.
figs. 65 a, 65 b (North Atlantic).
Uvigerina makes up its shell normally of three series- of inflated chambers, alternating
somewhat irregularly on an elongated spire. Its aperture is a very distinct and round
passage, generally tubular (Ectosolenian) and lipped. The lip is sometimes faintly
toothed, showing a relationship to the radiated mouth of the Polymorphina, Lagena ,
and JSfodosarina. To the last genus it is mostly related by its style of ornament, which,
as a rule, consists of strong well-marked costas, parallel to the axis of the shell. In all
large well-developed individuals, whether of typical or dimorphous growth, these costse
are distinct and strong, just as obtains in the large Lagence and Nodosarince (Plate XVIII.
figs. 16, 17). In weaker individuals the ribbing is less prominent and often becomes
obsolete in the newer chambers (Plate XIII. figs. 56 & 57). Certain dimorphous forms
are quite smooth (Plate XVIII. fig. 18). As in Nodosarice, some Uvigerinoe take on the
aculeate or hispid ornamentation ; the ribs of each chamber either sending back one or
more spines, or breaking up into prickles ; or the whole surface of the shell may become
spinose and bristly. The hispid forms of Uvigerina are generally found at great depths
(common at 1000 fathoms in the Tropical Atlantic, Indian Ocean, &c.), and are frequently
angular in section, belonging to the variety U. angulosa, Williamson. In deep water
also the large Uvigerinoe are frequently elegantly racemose, with a prickly surface ; the
chambers are globular and distinct, and the tubular mouth much elongated: this botryoidal
form is, as far as shape is concerned, the most deserving of the generic term “ Uvigerina"
given originally to the really typical costate U. pygmoea, such as we have before us.
Large Uvigerinoe of the typical form are especially abundant and well-grown in the
southern and eastern parts of the Mediterranean, at from 100-300 fathoms : the home
of Uvigerina seems to be in warm seas at this depth, but it is found also in shallower
water (Coralline-zone), but is then of the small size. Feeble forms creep upwards, as it
were, into shallow water, and downwards to great depths ; still the abyssal forms predo-
minate over the littoral, the latter retaining the greatest resemblance to the typical
■U.pygmcea; whilst the deep-water forms, whether angular or inflated, are prickly, the
angular forms in shallow water are ribbed.
In the elongated form, of feeble growth and faint striation (fig. 57), we may see a
tendency to a biserial and even a uniserial growth ; the chambers ceasing to retain a
definite triserial alternation ; and, becoming loose in their setting on, they present such
a condition as leads ultimately to a uniserial row of chambers in the newer part of the
shell. Such a dimorphous condition is clearly seen in certain figures, given by Soldani,
of Italian Uvigerinoe , named U nodosa by D’Orbigny (Ann. Sc. Nat. vol. vii. p. 269) ; and
we also possess similar forms both from the recent and the fossil deposit of the Medi-
terranean area, Plate XVIII. fig. 15. These dimorphous specimens present a growth of
either one, two, or three chambers in a straight line in the younger part of the shell
364
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
(still retaining the same kind of aperture), and with or without the intervention of a
biserial arrangement of chambers. This dimorphism of the Uvigerine type is seen best,
however, in specimens from shell-beds in the tropical and subtropical parts of the Indian
and Atlantic Ocean ; but in these the triserial mode of growth is obsolete, and even the
biserial is but feebly developed ; the result being a shell which, at first sight, might
easily be mistaken for a Nodosaria Raphanus. Close examination, however, shows the
short, wide, strongly labiate aperture of TJvigerina , markedly developed, and a plaiting of
the early chambers*. D’Orbigxy has figured, under the name of Sagrina gmlchella,
Foram. Cuba, pi. 1, figs. 23, 24, a specimen which was either the young, or an arrested
individual of such a biformed TJvigerina. Bigenerina amongst the Textulariae is the
isomorph of the above described dimorphous TJvigerina {Sagrina).
Not only is our Nodosariform TJvigerina connected with the typical TJ. jpygmcea (figs.
53-56) through Sagrina imlchella, D’Orb., but an intermediate condition between it and
the feebler dimorphs of the Mediterranean area occurs in the mud brought up by the
sounding-lead from the Abrohlos Bank {TJ. dimorpha).
Altogether, this latter group of forms shows how great the affinity is between the
always hyaline TJvigerina and the porous sandy Textularia..
The specimens figured in Plate XIII. figs. 53-57 are very common forms. The finest
individuals (figs. 53, 54) are from the mixed sands of the Norwegian coast. The feebler
specimens (figs. 55-57) are common in shell-sands from 30-70 fathoms at the Hunde
Islands, Davis Straits.
In the North Atlantic TJvigerina jgygmcea (Plate XVII. fig. 65) is large and common
throughout the eastern marginal plateau : wanting at great depths ; rare and middle-
sized north of the Bank ; and rather common and of middle size in Trinity Bay.
TJvigerina jpygmcea is world-wide in its distribution, and goes back at least to the
Middle Tertiary period.
TJvigerina jpygmcea, D’Orb., Var. angulosa , Williamson. Plate XIII. fig. 58 (Arctic);
Plate XVII. figs. 66 a, 66 b (North Atlantic).
Of this we have spoken above, page 363. This compressed condition turns up wherever
TJvigerince are at all common ; the ribbed or striated forms belonging to moderate depths.
In the mixed sands from Norway specimens were rather common.
In the North Atlantic TJ. angulosa is rare and small ; it occurs on the eastern marginal
plateau to the north of the Bank, and in Trinity Bay ; but was not found in the Abyssal
area.
Genus Orbulina.
Orbulina universa, D’Orbigny. Plate XYI. figs. 13, 14 (North Atlantic).
This is a monothalamous hyaline Foraminifer, globular and porous, of world-wide dis-
* A ribbed form fromtbe East Indian Seas is onr TJvigerina ( Sagrina ) RapTianus, Plate XYIII. figs. 16, 17 ;
and a smooth one from the Abrohlos Bank is our TJ. (/S'.) dimorpha, Plate XYIII. fig. 18.
FOBAMINIFEBA EBOM THE NOBTH ATLANTIC AND ABCTIC OCEANS.
365
tribution, found in shallow water in the Adriatic and other warm seas, but usually
frequent on sandy and muddy bottoms at not less than 30 fathoms and down to at least
2350 fathoms. It is richest in numbers where there is nothing but the calcareous matter
of Foraminifera. In the shallow water of our coasts Orbulina is poorly developed.
We have not recognized it fossil in strata older than the Middle Tertiary period.
In the North Atlantic the deep-sea soundings indicate that at 78, 90, 223, 329, 1660,
1950, and 2050 fathoms 0. universa is rare and of middling size; at 2350 fathoms it is
middle-sized and rather common; at 1776 and 2050 it is middle-sized and common; at
415 fathoms it is large and common ; and at 1750 and 2176 fathoms it is large but rare.
Genus Globigerina.
Globigerina bulloides, D’Orbigny. Plate XIV. figs. 1 & 2 (Arctic) ; Plate XVI. fig. 15,
and Var. infiata , figs. 16, 17 (North Atlantic). [See also Professor Huxley’s
Appendix to Commander Dayman’s Admiralty Keport, p. 65, pi. 4.]
Globigerina bulloides is the type of a distinct species, which is related to the monotha-
lamous Orbulina on one hand, and to the polythalamous Botalince on the other. Its
shell is composed of a series of hyaline and perforated chambers, of a spheroidal form,
arranged in a spiral manner, and each opening by a large aperture around the umbilicus,
in such a manner that the apertures of all the chambers are apparent on that aspect of
the shell, and form a large “umbilical vestibule.” This opening of the chambers into
one common vestibule is also characteristic of Carpenteria balaniformis. The extra-
ordinarily wild manner of growth of the latter is, to a certain degree, represented in
many of the larger specimens of Globigerina , which, losing the vesicular or botryoidal
form, become flat, outspread, and loosely lobulated or palmate. Although in these
respects, and also in the close resemblance of the young shells, these two species show
a near alliance, yet Globigerina seems, on the whole, from its general neat habit of
growth, and from its peculiar varietal groups, to be most nearly related to the Botalince
(. Flanorbulina and Discorbina). In fact, Globigerina and its varieties form an interesting-
group, Avhich may be regarded as central to the Planorbuline and Discorbine species and
their varieties, as well as certain species ( Pullenia and Splicer oidina) which were not until
lately recognized as related to the Botalince.
The chief varieties of Globigerina are peculiarly isomorphic of these other forms. The
large, extremely thick-walled, compact Globigerince , of the deepest waters, may stand as
the isomorphs of the equally abyssal solid specimens of Sphceroidina ; nor are the two
forms dissimilar at first sight. The smooth-walled compact Globigerince , such as have
been named Gl. infiata , D’Orb. (Foram. Canaries, pi. 2. figs. 7-9), come near in structure
to the highly polished, flush-celled, somewhat gigantic specimens of Pullenia obliquilo-
culata, Parker and Jones* (the type of which is the so-called Nonionina sphceroides ,
D’Orb.) from great depths. We have already mentioned the wild-growing Globigerina
* Caepentee’s ‘ Introd. Foram.,’ p. 183. See also Plate XIX. fig. 4.
MDCCCLXY.
O D
366
MR. W. Iv. PARKER AND PROFESSOR T. R. JONES ON SOME
( Gl . helicina , D’Orb. Ann. Sc. Nat. vol. vii. p. 277, after Soldani) as representing in its
own group a type of structure which has its completeness in Carpenteria. Like certain
varieties of Planorbulina farcta, hereafter to be described (Plate XIY. figs. 7-11), and
of Discorbina Turbo , Globigerina has nearly symmetrical (nautiloid) varieties ( Gl. hirsuta,
D’Orb. For. Canar. pi. 2. figs. 4-6, and Gl. pelagica , D’Orb., sp., For. Am. Mer. pi. 3.
figs. 13, 14) : by the possession of these forms Globigerina touches isomorphically several
other specific types, amongst which is Pullenia, its near relation, above referred to,
typically symmetrical. Such an assumption of symmetry in these simple, vesicular,
discoidal Foraminifers is interesting, as suggestive of a tendency to attain the more
regular nautiloid form, normal amongst the higher forms, such as Nummulina, Cyclo-
clypeus, Heterostegina, Polystomella, and others, which, on their part, when feebly
developed, are apt to be asymmetrical. Indeed in this respect we have a connecting
link between the higher and the lower group in Amphistegina, a congener of the true
Nummulince , but simpler in structure and essentially asymmetrical.
The foregoing observations on the relationships of Globigerina will assist us in eluci-
dating the alliances of many of the species and varieties about to be described, lying
between the simple monothalamous Orbulina and those highest in the scale [Polystomella
and Nummulina ), which give the fullest expression of the type of structure possessed by
this Rhizopodous order.
The affinities and isomorphisms of Globigerina , however, are not exhausted by the
consideration of the groups above referred to ; for the small and feebly developed indi-
viduals of the typical Globigerina bulloides , which are so extremely abundant in the deep
seas, mixed with large specimens, are imitated by the small, vesicular, weakly grown
Textularice , Uvigerince, Pulimince, and Cassidulince ; and we might even include the dwarf
vesicular Lituolce of deep waters (see Plate XV. figs. 46, 47, and Plate XVII. figs. 96-98).
Figs. 1 & 2 are relatively small specimens of Globigerina bulloides , such as are found
in shallow seas all the world over, and also (as above mentioned) in abyssal depths,
where they are in company with large individuals ; the latter live in deep water only.
There is but little exogenous growth on the primary perforated chamber-wall of such
Globigerince as those before us ; but in deeper water, as a rule, a large proportion of the
individuals have a thick deposit of exogenous shell-matter, which generally rises into
reticulate ridges, surrounding the pseudopodian passages, and giving the surface a roughly
honeycombed appearance. Sometimes these ridges are developed into asperities, prickles,
needles, and even large tubules. The latter are sparsely scattered ; are formed of the
divergent growth of the whole areola around the pseudopodian passage ; and occur on
the symmetrical, nautiloid forms, such as occur at 1600-1700 fathoms between Malta
and Crete. The acicular appendages arise at the junctions, or on the edges of the
areolae, and are found on some symmetrical varieties. Such are very abundant in the
Red Sea at from 300-700 fathoms ; and here the needles are often so long on the peri-
pheral parts of the older chambers that they subdivide the large arched aperture of the
last chamber into narrow oblong openings.
EOEAMINIEEEA EEOM THE NORTH ATLANTIC AND AECTIC OCEANS. 367
The chamber-walls attain their greatest thickness in those close-set and rough-shelled
varieties which occur in great abundance at from 1600 to 2400 fathoms in the North
Atlantic, between Ireland and Newfoundland (Plate XVI. fig. 15 ; and Professor Huxley’s
plate in the Admiralty Report on the Telegraph-soundings in the North Atlantic), and
at lat. 5° 37' S., long. 61° 33' E. in the Indian Ocean (2200 fathoms). These are the
nearest isomorphs of Sphceroidina dehiscens , Parker and Jones, Plate XIX. fig. 5, which is
found with them in the tropical parts of the Atlantic and in the Indian Ocean, and not
in the North Atlantic. Those smooth forms ( Gl. infiata , D’Orb., from the Canaries) having
moderately thick chamber-walls, and which are nearest to Pullenia in style of growth,
abound in the North Atlantic (Plate XVI. figs. 16, 17), and are very plentiful in the
Southern Mediterranean, at about 700 fathoms, and in the Indian Ocean, lat. 36° 58' S.,
long. 51° 49' E. (900 to 1120 fathoms). Gl. bulloides is small and very abundant at 2700
fathoms in the South Atlantic ; the greatest depth for its habitat that we know of.
The complanate form of Globigerina, with more or less limbate septal lines, is figured
by D’Orbigny, as living on the coast of Cuba, with the name of Bosalina Linnwi (Foram.
Cuba, pi. 5. figs. 10-12). It is common in the Chalk, and is known as Bosalina margi -
nata, Reuss (Charakt. Kreid. Ostalpen, Henksch. Akad. Wien, vii. pi. 26. fig. 1), and
Bosalina canaliculata , Reuss (Ibid. fig. 4).
Plate XIV. figs. 1 & 2 represent specimens obtained at three places among the Hunde
Islands by Dr. P. C. Sutherland (28-30, 30-40, and 60-70 fathoms), rather common
and small ; and others found (rare and very small) in the most northern soundings we
have examined, namely, Baffin’s Bay, lat. 76° 30' N., long. 77° 52' W. (Parry) at 150
fathoms; and others from the coast of Norway, few and small in the mixed sands
(MacAndrew and Barrett).
In the North Atlantic Globigerina bulloides , including its variety Gl. infiata , D’Orb.
(Plate XVI. figs. 16, 17), is spread broad-cast ; but is abundant and of good size only at
the greater depths (“Virginian Province,” and the “Celtic” and “Boreal ” abyssal areas,
at upwards of 2000 fathoms in some places), and at 223, 338, and 415 fathoms on the
eastern marginal plateau : elsewhere on this plateau it is small and varying in numbers.
On the western plateau (north of the Bank of Newfoundland) it is small, though some-
times common ; whilst in Trinity Bay it is very small and very rare.
The oldest known Globigerince are those in the Gault.
Globigerina bulloides , Var. infiata , D’Orbigny. Plate XVI. figs. 16,17 (North Atlantic).
In this Globigerina (For. Canar. p. 134, pi. 2. figs. 7-9), peculiar for its large gaping
aperture, the newer chambers are relatively larger than usual, and cover the former ones
to a great extent (see figs. 16, 17). It is variable in its details, and does not differ
specifically from Gl. bulloides. It has already been referred to above (page 365).
This variety abounds and is large on the North Atlantic, and on deep muddy bottoms
in the Mediterranean (Dayman’s soundings). Professor Bailey noticed it in soundings
from off the Coast of New Jersey (see Appendix). D’Orbigny had it from the Canaries;
it is plentiful in the Indian Ocean (see above).
3 d 2
368
ME. W. K. PAEIvEE AND PEOFESSOE T. E. JONES ON SOME
From some mounted specimens lent to us by Mr. F. Galton, F.R.S., we may add the
following notes as to the Globigerince of the North Atlantic. See also Appendix I.
At 1650 fathoms the deep-sea ooze consists chiefly of Globigerince , many of them of
large growth (as if well-nourished), thick-shelled and rough, the sarcode remaining
(brown) in most of the larger shells ; and at the same time there are very many small
and delicate individuals (just as is the case with other Foraminifera, — minute dwarfs
accompanying full-grown specimens of one and the same type). With Globigerina at
this depth occur a rather small Hotalia Beccarii , a very small Bulimina (1), and siliceous
Sponge-spicules. At 1600 fathoms Globigerince as above, with a small Spirillina. At
1500 fathoms Globigerince appear as at 1650 fathoms. The thickness of the chamber-
wall is relatively great. A sponge-gemmule was also found here.
I)r. G. C. Wallich has well illustrated Globigerina and Orbulina in plate 6 (unde-
scribed) of the First Part of £ The North-Atlantic Sea-bed,’ 1862.
Globigerince are (as is well known) among the most characteristic of deep-sea Foramini-
fera (Abyssina) ; and these form a group that love to live at from 1000 to 2500 fathoms.
They are Pullenia , Sphceroidina, Globigerina , and its monothalamous congener Orbulina
The first three are always rare and small in shallow water ; and Orbulina usually has
similar conditions.
Cassidulina is also an abyssal form ; but lives well up to 30 fathoms, though in flatter
and more delicate forms than it has lower down.
Genus Pullenia.
Pullenia sphceroides, D’Orbigny, sp. Plate XIV. figs. 43 a, 43 b (Arctic) ; Plate XVII.
fig. 53 (North Atlantic).
For an account of Pullenia , one of the deep-sea forms, probably allied to Globerigina,
though resembling Nonionina , see Carpenter’s Introd. Foram. p. 184 ; it is the Nonio-
nina sphceroides, D’Orb. Modeles, No. 43, Ann. Sc. Nat. vol. vii. p. 293, No. 1 ; and A.
bulloides of the same author, For. Foss. Vienn. p. 107, pi. 5. figs. 9, 10, and Ann. Sc.
Nat. vol. vii. p. 293, No. 2.
Our figure 43 is of normal shape, but small size, as are all those which we find in the
Arctic and North Atlantic seas. Another form of Pullenia has the chambers set on
obliquely (P. obliquiloculata, Parker and Jones, Plate XIX. fig. 4). In the mixed sands
from Norway Pullenia splicer oides is rather common and small : it is rare and small,
often very small, at 1776, 2035, 2176, and 2330 fathoms in the North Atlantic; also at
1203 fathoms north of Newfoundland Bank, and at 200 fathoms on the plateau off
Ireland.
Fig. 53 is the Isonionina guingueloba , Reuss, Zeitsch. Deutsch. Geol. Ges. vol. iii. pi. 5.
fig. 31, an enfeebled, somewhat flattened form, of looser growth than usual. It occurs
also in the Eocene Clays of Hants and the Isle of Wight (H. B. Brady), in the ‘ Septa-
rian Clay’ (Eocene) near Berlin (Reuss), and recent in the Red Sea.
Pullenia sphceroides lives in the Mediterranean, the Red Sea, and South Atlantic at
from 30-320 fathoms.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 369
Genus Speleroidixa.
Sphcefoidina bulloides, D’Orbigny, sp. Plate XVI. fig. 52 (North Atlantic).
This peculiar species (of which Sph. dehiscens is another variety) is related to Globi-
gerino ; and, together with Pullenia , Orbulina , and Globigerina , essentially of deep-
water habits, is small and rare in the North Atlantic, but large in the Tropics.
Sphceroidina has a small spire, somewhat irregularly wound, the vesicular chambers (of
which only three or four are visible) hiding the spiral arrangement. Reuss has figured
many specimens ( Sph.Austriaca ) in pi. 51, Denkschr. K. Akad. Wissen. Wien, vol. i. 1850.
Sphceroidina dehiscens , Parker and Jones, is largish, thick-shelled ; the chambers not
closely applied, and their edges roughly everted and jagged (Plate XIX. fig. 5).
Sph. bulloides is rare and small at 223 fathoms on the marginal plateau off Ireland;
very rare and very small at 2330 fathoms in mid-ocean.
In the Mediterranean it occurs at 320 fathoms, in the Red Sea at 372, in the Tropical
Atlantic at 1080, in the Southern Atlantic at 260 and 940, and in the Indian Ocean at
2200 fathoms.
Genus Textularia.
Textularia agglutinans , D’Orbigny. Plate XV. fig. 21 (Arctic).
Textularia agglutinans , D’Orbig. (Foram. Cuba, p. 144, pi. 1. fig. 17, 18, 32-34), in
its ordinary and moderately developed condition, gives a fuller idea of the species than
any other variety.
We have it in the mixed sands from Norway rather common and of middle size; and
at the Hunde Islands it is small, rare at 30-40 fathoms, rather common at 25-30
fathoms.
Textularia agglutinans is world-wide ; and has its representatives in many Tertiary
and Secondary strata.
Textularia agglutinans , Var. abbreviata, D’Orbigny. Plate XVII. figs. 76 a, 76 £ (North
Atlantic).
T. abbreviata, D’Orb. (For. Foss. Vien. p. 249, pi. 15. figs. 7-12), is a short form,
intermediate to T. gibbosa, D’Orb. Modeles, No. 28, and T. agglutinans, D’Orb., and
smaller than either ; but, like them, it is sandy.
We have it from the marginal plateau of the Atlantic off Ireland, where it is common
and middle-sized at 43 and 78 fathoms ; rather common and middle-sized at 90 fathoms ;
rare and small at 223 fathoms; rather common and small at 415 fathoms.
T. abbreviata has much the same range as its type T. agglutinans.
Textularia agglutinans , D’Orbigny, Var. Sagittula , Defrance. Plate XVII. figs. 77 a,
77 b (North Atlantic).
T. Sagittula , Defrance (see ‘Annals Nat. Hist.’ 3rd ser. vol. xi. p. 91, &c.), is the
common, often small, sandy, triangular variety of T. agglutinans , D’Orb.
370
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Our figures indicate a normal specimen of this form from the marginal plateau off
Ireland, where it is common and of middle size at 78 fathoms.
T. Sagittula is world-wide, and common in many Tertiary deposits.
Textularia agglutinans, Y ax. jpygmcea, D’Orbigny. Plate XV. fig. 22 (Arctic); Plate
XVII. figs. 78 a, 78 b (North Atlantic).
This is the common, small, hyaline or clear-shelled, perforate Textularia ; its sandy
analogue is T. Sagittula. Normal specimens are figured here.
We have it in the mixed sands from Norway, common and middle-sized.
In the North Atlantic it is rather common and small at 78 and 90 fathoms on the
marginal plateau ; and it is rare and small at 200 and 415 fathoms, rare and middling
at 223 and 338 fathoms on the same ground: in the abyssal depth (Boreal) it is rare
and small at 2033 fathoms; and nearer to the Bank it is very rare and very small at
1450 fathoms.
T. jpygmcea , D’Orb. Modeles, No. 7 (the same as T. aciculata, D’Orb., Ann. Sc. Nat.
vol. vii. p. 263, pi. 11. figs. 1-4), has a distribution similar to that of the other chief
"varieties.
Textularia agglutinans, Var. carinata, D’Orb. Plate XVII. figs. 79 a, 79 b (N. Atlantic).
The shell of T. carinata , D’Orb. (For. Foss. Vienn. p. 247, pi. 15. figs. 32-34), is flatter
than that of either T. pygmcea or T. Sagittula ; the edges becoming very thin and more
or less produced into a sharp keel ; and the chambers extend backwards irregularly.
The specimen figured is a small and feeble individual of this variety. Still more flat-
tened is our new variety T. Folium , from the Australian coast, Plate XIX. fig. 19.
T. carinata in the London Clay frequently has a spiral arrangement of its earliest
chambers, such as is seen also in many other varieties of Textularia. In fig. 79 a a
faint tendency to a coil is seen at the apex of the specimen.
On the marginal plateau off Ireland T. carinata occurs rather common and small at
78 and 90 fathoms. It is found in the Adriatic and other seas, extremely large between
Socotra and Kurachee ; also fossil in the Tertiary deposits.
Textularia agglutinans , D’Orb., Var. biformis , nov. Plate XV. figs. 23, 24 (Arctic).
These very small Textularice have a sandy shell, often of a rusty colour, with scarce
any shell-substance proper. They have a spiral commencement (a not uncommon
feature in Textularia), and the later chambers are subquadrate, arranged alternately.
This may be regarded as an arrested form of T. annectens , Parker and Jones (Annals
Nat. Hist. 3rd ser. vol. xi. p. 92, fig. 1) ; for, if better developed and carried on with
uniserial chambers, it would be equivalent to that variety. It is common in the Gault
and Chalk with T. annectens.
Textularia biformis is common and small at the Hunde Islands in 60 to 70 fathoms.
EOEAMINIEERA FKOM THE NORTH ATLANTIC AND AECTIC OCEANS. 371
Textularia agglutinans , Yar. ( Bigenerino ) Nodosaria, D’Orb. Plate XV. fig. 25 (Arctic);
Plate XVII. figs. 80 a, 80 b (North Atlantic).
Bigenerince are Textularice that commence with alternate biserial chambers and com-
plete themselves with a uniserial set, the aperture becoming terminal, central, round,
and sometimes pouting.
JBigenerina Nodosaria , D’Orb. (Ann. Sc. Nat. vol. vii. p. 261, pi. 11. figs. 9-12; and
Modele, No. 57), is usually sandy, and commences with flat interlacing of chambers, as
in T. agglutinans, D’Orb. ; whilst B. digitata, D’Orb. (Modele, No. 58), begins with a
conical set of chambers, as in T. gibbosa, D’Orb.
At the Hunde Islands (Dr. Sutherland) B. Nodosaria is extremely small, but common,
at 60 to 70 fathoms.
On the marginal plateau off Ireland it is common at 78 and 90 fathoms, coarsely
arenaceous and of fair size.
B. Nodosaria lives in the Mediterranean and other seas, being widely distributed ; it
keeps a good size, and prefers muddy bottoms, flourishing down to 200 or 300 fathoms.
Textularia agglutinans , -Var. [Bigenerino) digitata, D’Orbigny. Plate XVII. fig. 81
(North Atlantic).
B. digitata, D’Orb. (Modele, No. 58), may be said to be a smooth, rusty subvariety
of B. Nodosaria, with a conical instead of flattened apex.
On the marginal plateau of the North Atlantic B. digitata is rare and small at 78
fathoms ; the figured specimen is obscure, and may be regarded as feebly developed.
B. digitata occurs in company with B. Nodosaria in the Mediterranean and elsewhere.
Textularia agglutinans, D’Orb., Var. ( Verneuilina ) polystropha, Iteuss, sp. Plate XV.
fig. 26 (Arctic).
When Textularice have a triple row of alternating chambers, as is not unusual with
them, they are termed Verneuilince ; having commenced triserially, they may afterwards
take on a biserial or uniserial arrangement of chambers, and are known as Gaudryince,
Clavulince, &c. Some that have a triple series of chambers are so much twisted on the
axis as to have a Buliminoid aspect ; a slight approach to this condition is shown in
Verneuilina polystropha ( Bulimina p o ly stropha , Reuss, Bohm. Kreid. vol. ii. p.109, pi. 24.
fig. 53 ; Polymorphina silicea, Schultze ; Bulimina arenacea, Williamson). In Verneuilince
the aperture ceases to be transverse, becoming drawn upwards, as it were, across the
septal plane more and more in the later chambers, until it ceases to be even a notch,
and becomes terminal and round, as it is in Bigenerince.
V. poly stropha may be said to be a small, vesicular, arrested Verneuiline Textularia-,
sandy, twisted on its axis, and very red in colour. It is of wide distribution, living in
all latitudes ; and is found fossil in the Tertiary and Cretaceous beds.
It is often of much larger size than our figured specimen, which is from the Hnnde
Islands (Dr. Sutherland); where V. poly stropha is common and small at 25-40 fathoms,
and very common and small at 60-70 fathoms.
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Genus Bulimina.
Bulimina Presli , Reuss, Var. Pyrula , D’Orbigny. Plate XV. figs. 8, 9 (Arctic).
In describing the Bulimince that form part of the Rhizopodal Fauna of the Arctic
and North Atlantic Oceans, we have not occasion to treat so largely of the special cha-
racters of the genus, nor the relationships of the subspecific groups, as is necessary in
the case of the Nodosarince , Lagenae, Polymorphince , JJmgerinae , Globigerince, Botcilince ,
and Polystomellce ; chiefly because these relationships and characters are not difficult to
be understood, with the help of the figures before us, and because they have been clearly
stated in Carpenter’s ‘ Introd. Foram.,’ p. 195, &c.
As the best medium-form of the very variable Bulimince we take Reuss’s B. Presli
(Verst. Bohm. Kreid. pi. 13. fig. 72 ; Haiding. Abhandl. iv. pi. 10. fig. 10; and Car-
penter’s ‘ Introd.’ pi. 12. fig. 18). B. Pyrula , D’Orb. (For. Foss. Yien. pi. 11. figs. 9, 10),
of which we have some Norwegian specimens before us, is one of the varieties (for we
cannot see evidence of the existence of more than one species of Bulimina ) that have
the greatest tendency to overlap their chambers, and so hide the primary segments by
the later ones closing over them. It is usually prickled at the apex.
We have it common and large in the mixed sands from the coast of Norway
(MacAndrew and Barrett). It lives in the Mediterranean, and is large between Socotra
and Kurachee. It is found fossil in the Vienna Tertiaries (where it is large) and the
London Clay. A Bulimina of very similar shape occurs also in the Upper Triassic Clay
of Chellaston, Quart. Journ. Geol. Soc. xvi. p. 457, pi. 20. fig. 45.
Bulimina Presli, Reuss, Var. marginata, D’Orbigny. Plate XV. fig. 10 (Arctic); Plate
XVII. fig. 70 (North Atlantic).
The neat, little, acute-ovate Bulimince that next come under notice are characterized
by the exogenous growth of shell-matter, in the form of prickles, on the primordial
chamber (as in B. Pyrula also) and at the posterior edges of the other chambers to a
greater or less degree.
The edges of the chambers may be pinched up, crenulated, serrated, toothed, or spined ;
the spines may be few or numerous along the sharpened border or on the surface of the
chambers, and they may be present on all of them or limited to the earlier ones ; inter-
mediate conditions in every respect being observable. No real division can be made
amongst these modifications ; but for convenience-sake those edged with prickles are
grouped under B. marginata , D’Orb. Ann. Sc. Nat. vol. vii. p. 269, No. 4, pi. 12. figs.
10-12 ; whilst B. aculeata , D’Orb. (after Soldani), Ann. Sc. Nat. vol. vii. p. 269, No. 7,
takes those with fewer spines. Williamson’s B. gmjpoides , var. spinulosa , Monogr. p. 62,
pi. 5. fig. 128, has many fine long spines along the margins. The crenate and prickly
margins are found associated with more contracted forms of Bulimince * than those
* Such as B. pulcTiella, D’Orb. (For. Amer. Mer. p. 50, pi. 1. figs. 6, 7), a very small subcylindrical form,
■with pincbed and fringed chambers ; living in the Pacific, from the equator to 34° S. lat. ; and B. Pcitagonicci,
D’Orb. (Ibid. p. 50, pi. 1. figs. 8, 9), a very rare form (contracted and fringed at first, irregularly globuliform
afterwards), found at the Bay of San Bias, Patagonia.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
o I o
above-mentioned ; but the exogenous growths belong to thick-shelled specimens, and
probably indicate favourable habitats ; on the thin-shelled and the attenuate forms there
is little or no fringing or other ornament.
Fig. 10. Plate XV. has the chambers somewhat extended by their produced spiny
edge or prickly fringe, and has a long apical spine ; such forms, with others (as fig. 11)
with less of the marginal spines, occurred common and of middle size in the mixed sands
from Norway (MacAndrew and Barrett).
Plate XVII. figs. 70 a, 70 b, 70 c (North Atlantic).
Figs. 70 a Sc 70 b, Plate XVII., differ somewhat one from the other and from fig. 10,
Plate XV., in the marginal and caudal spines; but no two specimens, even among many,
are exactly alike.
They are common and large at 43 fathoms; common and middling at 78 and 90
fathoms; and common and small at 223 and 415 fathoms, on the plateau off Ireland in
the North Atlantic.
B. marginata lives in all seas, at no great depths.
Bulimina Presli , Eeuss, Var. acuieata , D’Orbigny. Plate XV. fig. 11 (Arctic) ; Plate
XVII. figs. 68 & 69 (North Atlantic).
In these specimens the chambers have a well-marked globosity, and favourable con-
ditions of growth have given them a rapid rate of increase, as in the foregoing sub-
variety ; the exogenous prickles, however, are less largely developed, being confined for
the most part to the earliest chambers.
Fig. 11, Plate XV. is an intermediate form, from Norway (mixed sands), with fewer
marginal spines than some of its congeners ; and though more spinous than figs. 68 & 69,
yet, as these are essentially marginatce also, and as there is a difference of degree and
not of kind, not only among these, but between these and others presently to be described,
it is placed under B. acuieata as its fittest place in the grouping. Its chambers have
sharp posterior edges, drawn out into comparatively few spines, short and strong ; and
it has a strong double caudal spine.
B. acuieata , D’Orb., is sufficiently well figured by Soldani, Testae, vol. i. part 2,
pi. 127. fig. 1, pi. 130. fig. vv , and pi. 131. fig. xx (the last has been unnecessarily sepa-
rated by D’Orbigny as B. trilobata).
Plate XVII. figs. 68 & 69 (North Atlantic).
In figs. 68 & 69, Plate XVI. the chambers are globose, and the earliest alone are
armed with spiny excrescences. A less developed form appears in our next variety (fig. 67).
Figs. 68 & 69 are from the eastern marginal plateau at 223 fathoms, where B. acu-
ieata is common and of middle size.
B. acuieata is found everywhere with B. marginata and B. ovata.
mdccclxv.
3 E
MR. W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
374
Bulimina ovata , D’Orbigny. Plate XVII. figs, 67 a , 67 b (North Atlantic).
Among the Bulimince that fall short of the fair growth of the type ( B . Presli , Peuss) *
are B. ovata, D’Orb., B. pupoides, D’Orb., and others which have a more or less subcy-
lindrical form owing to the somewhat slow rate of increase in the successive chambers.
Professor Williamson took B. pupoides as the type when describing the British Buli-
mince, ‘Monograph,’ p. 61, &c.
B. ovata , D’Orb., For. Foss. Yien. p. 185, pi. 11. figs. 13 & 14, is just such a varietal
form as occurs in the North Atlantic ; on the Irish plateau, rare and small at 78 fathoms ;
rare and very small in the abyssal area at 1776 and 1950 fathoms; rare and middle-
sized at 740 fathoms, north of the Bank; very rare and very small at 150 fathoms in
Trinity Bay.
It is a British form (B. pupoides, var. fusiformis, Williamson, Monogr. p. 63, pi. 5.
figs. 129, 130), together with the almost identical B. pupoides, D’Orb.; both of which
are found fossil (and large) in the Vienna Tertiaries. It is large also in fossil beds at
Jamaica (Barrett). In Captain Pullen’s Soundings from between Socotra and Kura-
chee it is very large (sometimes thin-shelled). B. ovata accompanies the other Bulimince.
They prefer muddy bottoms; flourishing in depths as great as 100 or 150 fathoms; and
in the fossil state they are found in clays, corresponding to mud-beds.
Fig. 67 a shows a slight amount of exogenous growth on the early chambers, sufficient
to indicate the close relationship of habit between this and its better grown allies
(figs. 68 & 69).
Bulimina Presli , Peuss, Var. Buchiana , D’Orb. Plate XVII. fig. 71 (North Atlantic).
In this elegant little form we find the largest relative proportion of shell-matter
among Bulimince , which, on the other hand, are often very thin-shelled, but often
thicker in deep seas. The chambers are here laid closely one on another, fitting well,
nearly hiding their septa, and bearing vertical superficial ridges, sparse and strong, in
which the marginal spines, seen in other varieties, are lost; just as spinos e Lagence,
Nodosarice , &c. pass into ribbed varieties by modifications of the ornament. B. Buchiana
is the most Uvigerine, both in shell-structure and shape, of all the Bulimince.
B. Buchiana , D’Orb., For. Foss. Vien. pi. 11. figs. 15-18, is widely distributed;
though never common. It is found in the Mediterranean; but, in comparison with
B. ovata and B. marginata, it is rare : it is fossil near Vienna.
On the marginal plateau off Ireland it is rare and small at 78 fathoms.
Bulimina Presli , Peuss, Var. elegantissima, D’Orbigny. Plate XV. figs. 12-17 (Arctic).
Some Bulimince have their segments or chambers lengthened sideways and set on very
obliquely to the axis of the spine, the greater part of the shell being made up of thn
last whorl of from seven to ten chambers. More especially in short and gibbose indi-
viduals some of these many chambers are smaller than others in the whorl, and appear
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
375
to interdigitate or to be intercalated. Bulimina elegantissima , D’Orb., For. Amer.
Merid. p. 51, pi. 7. figs. 13, 14, and Bobertina arctica , D’Orb., For. Foss. Yien. p. 203,
pi. 21. figs. 37, 38, both belong to this group of Bulimince (see Carpenter’s Introd.
Foram. p. 195, &c.), and the differences of modification are so slight that we include the
latter in the former.
Our Arctic specimens of B. elegantissima are relatively large in size and thin-walled.
In the Indian seas B. elegantissima occurs smaller, and with thicker walls ; but from
the Australian seas we have it more elongate and stronger than the Arctic form. The
elongate form is found also on the British coasts (see Williamson’s 4 Monograph,’ p. 64,
pi. 5. figs. 134, 135). B. elegantissima occurred to D’Orbigny in the sea-sands from the
Pacific coast of South America; and he had Bobertina arctica from the North Cape.
B. elegantissima is rare and of middling size at 25-30 fathoms, and common and large
at from 30-70 fathoms, at the ITunde Islands (Dr. P. C. Sutherland’s dredgings).
It is fossil at Grignon; also in the Eocene sandy clays of Hants and Isle of Wight
(FI. B. Brady), and in the Pliocene clay under the fens near Peterborough. In the
recent state it is world-wide, — the British coasts, the Mediterranean, Bed Sea, Tropical
Atlantic, Australia, and Fiji.
Bulimina Presli, Beuss, Var. ( Virgulina ) Schreibersii , Czjzek. Plate XV. fig. 18
(Arctic); Plate XVII. figs. 72, 73 (North Atlantic).
Virgulince are such Bulimince as are very much outdrawn, with thin shells, and having
long loop-like apertures, with inverted lips, as in Bulimina proper. The chambers are
arranged less compactly than in the other Bulimince , in consequence of the elongation of
the shell, and are scarcely more than biserial, or even only irregularly so. V. Schreibersii,
Czjzek, Haid. Abhandl. vol. ii. pi. 12. figs. 18-21, is of irregular growth, intermediate
between the long and loose-growing varieties of B. ovata, D’Orb., and the Textulariform
Virgulina squamosa, D’Orb., next described. It is an isomorph of Polymorpliinci, as
V. squamosa is isomorphic with Textularia.
We have it rare and large from the Hunde Islands, where Dr. Sutherland dredged it
in 30-40 fathoms; and in the North Atlantic it is rare and middle-sized at 1950
fathoms; rare and large at 2330 fathoms (Boreal portion of the Abyss); and rare and
small at 954 and 725 fathoms north of Newfoundland Bank.
V. Schreibersii and its subvarieties are not rare in existing seas, both of warm and cold
climates ; and it occurs fossil in the Tertiary beds of Sienna, Vienna, and Turin.
Some allied forms occur in the Chalk and in the Clays of the Oolite, which are
isomorphs of the Dentaline or Virguline Po lymorp hi n ce of the Sutton Crag.
Bulimina Presli, Beuss, Var. ( Virgulina ) squamosa, D’Orbigny. Plate XV. fig. 19 a,
19 b, 20 (Arctic).
Although the arrangement of the chambers has become almost regularly biserial, and
alternate, as in Textularia , yet this variety retains the true Bulimine aperture; and
3 e 2
376
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
gradual modifications in form lead us from Virgulina squamosa , D’Orb. (Modele,
No. 64), before us, through V. Schreibersii (fig. 18), to the more regular Bulimince.
This variety has the same world-wide distribution as V. Schreibersii ; but is never
common: at the Hunde Islands it is rare and small at 30-40 and 60-70 fathoms; and
it was rare and large in the mixed sands from Norway.
As an enfeeblement of Bulimina, it points in one direction to V. Schreibersii , and in
another to the Bolivince. Fig. 20 is a specimen that can scarcely be separated from
Bolivina 'punctata.
Bulimina Presli, Reuss, Yar. (Bolivina) costcita, D’Orbigny. Plate XVII. fig. 75 (North
Atlantic).
“ A more decided modification of the Bulimine type is presented by those forms which
have been ranked by D’Orbigny in his genus Bolivina ; the arrangement of the segments
being here regularly biserial and alternating, as in Textularia ; but the aperture never
loses the elongation and the inversion of its lips, characteristic of the Bulimine type,
and its direction is usually somewhat oblique. In the B. costata of D’Orbigny (For.
Amer. Merid. p. 62, pi. 8. figs. 8, 9) there is a set of right parallel costae, running con-
tinuously from one segment to another along the entire length of the shell, giving to it
a very peculiar aspect” (Carpenter, ‘ Introd.’ p. 196).
The inversion of the lip of the aperture, characteristic of Bulimina , and homologous
with the intussusception of the neck-tube in Lagena , is well seen in some young trans-
parent Bolivince.
B. costata is rare and large at 223 fathoms on the marginal plateau off the coast of
Ireland. D’Orbigny found it common at 20 metres at Cobija, South America; an
allied and small variety, B. plicata (op. cit. pi. 8. figs. 4-7), he found in deeper water at
Valparaiso.
B. costata lives on muds and is found fossil in clays, like other Bulimince ; flourishing
down to about 100 fathoms ; it is never common, but is found on the west coast of Scot-
land, and from the south coast of England (Eastbourne) to the tropics.
Bulimina Presli , Reuss, Var. (Bolivina) punctata , D’Orbigny. Plate XVII. fig. 74
(North Atlantic).
The figured specimen is a short and vesicular subvariety of B. punctata , D’Orbigny.
(For. Amer. Merid. p. 63, pi. 8. figs. 10-12), which is the centre of a group of many
forms. The one before us is perfectly Textulariform, and can be diagnosed as a Bulimina
only by the shape and subobliquity of its aperture.
We find it rare and small at 43 and 415 fathoms, and rather common and small at
223 fathoms, on the marginal plateau off Ireland.
D’Orbigny got it rather common at from 40 to 50 metres at Valparaiso.
B. punctata is world-wide, reaching as low as 100 fathoms. In the Mediterranean
area it is both recent and fossil. It is present in the Oxford and Kimmeridge Clays.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
377
Genus Cassidulina.
Cassidulina Icevigata , D’Orbigny. Plate XV. figs. 1-4 (Arctic); Plate XVII. figs. 64 a,
64 b , 64 c (North Atlantic).
Cassidulina , related to Bulimina and Textularia , is described in Carpenter’s Introd.
Poram. p. 197. It is of world-wide distribution, on muddy bottoms in both shallow and
deep waters. In the Indian Ocean (between Socotra and Kurachee) Cassidulina takes
on the uncoiled condition (Cassidulina Pupa, D’Orb., Ehrenbergina serrata , Eeuss) ; and
in the tropical deep seas it passes into thick-walled, flush-shelled, and uncoiled forms,
isomorphic of Bolivince. It occurs in Tertiary deposits. Deep-sea forms are usually
thick-walled.
C. Icevigata , D’Orb. (Modeles, No. 41, Ann. Sc. Nat. vii. p. 282, pi. 15. figs. 4, 5 bis)
is common and small in the mixed sands from Norway (MacAndrew and Barrett) ;
common and middle-sized at the Hunde Islands, from 30 to 70 fathoms*; common and
middle-sized in 150 fathoms, 76° 30' lat., 77° 52' long., Baffin’s Bay, and rare and middling
at 75° 10' lat., 60° 12' long.
In the North Atlantic it is rare and small at 1750 fathoms in the central area ; north
of the Bank it is rare and of middle size at 102, 112, and 145 fathoms, and rather
common at 740 fathoms ; in Trinity Bay it is rare and small at 150 fathoms, middle-sized
and not very common at 124, 133, and 192 fathoms.
On the Newfoundland Bank Cassidulince are few and probably dead, just as Nonio-
nina S capita occurs. Cassidulina is also a Middle Tertiary form.
Cassidulina Icevigata , D’Orb., Var. crcissa, D’Orb. Plate XV. figs. 5, 6, 7 (Arctic);
Plate XVII. fig. 64 d (North Atlantic).
This thicker form accompanies the typical C. laevigata in its wide-spread occurrences.
D’Ordigny first described and figured C. crassa from off Cape Horn (160 metres), and, in
company with C. Pupa, from the Falkland Isles (“at a considerable depth”). Professor
Williamson’s C. obtusa (Monogr. p. 69, pi. 6. figs. 143, 144), from the British coasts,
and from the Hunde Islands, is the same as C. crassct , excepting a slight difference in
the variable aperture.
C. crassa , D’Orb. (For. Amer. Mer. p. 56, pi. 7. figs. 18—20) is small at 28-30 and
50-70 fathoms, and of middle size at 30-40 fathoms at the Hunde Islands, and common
throughout ; it is common and small at 150 fathoms in Baffin’s Bay, 76° 30' lat., 77° 52' long.
On the eastern plateau of the North Atlantic it is very rare and very small at 223
fathoms.
C. crassa has its finest development (as far as we know) at 1100 fathoms in the Tro-
pical Atlantic ; like C. laevigata it is often among the deep-sea forms ; it is found also in
the Mediterranean and in Bombay Harbour.
* Professor Williamson (Monogr. p. 68) notices the nmhonate and transparent condition of the Cassidulince
from the Hunde and Beechey Islands.
378
ME, W. K. PAEKEE AMD PEOPESSOE T. E. JONES ON SOME
Genus Planorbulina.
Planorbulina farcta, Fichtel and Moll, sp. (Varieties). Plate XIV. figs. 3-11 (Arctic);
Plate XVI. figs. 18-25 (North Atlantic).
This is a very common variety of a species belonging to the Rotaline group of Fora-
minifera. In endeavouring to elucidate the relationships of the Botalince, we have been
impressed with the distinctiveness of nine specific groups, six of which have more or less
of the well-known Potalian shape, and are extremely rich in varietal forms (see Dr.
Carpenter’s ‘ Introd. Study Foram.’ Ray Soc. 1862, pp. 198, &c.). A great proportion
of these varieties have been described by authors under the generic term “ Rotalia”;
others have been grouped under the leading names of Bosalina, Planorbulina , Gyroidina,
Anomalina , Tru/ncatulina , and several others, supposed to be of subgeneric, or even of
generic, value. An artificial classification and extreme confusion have been the conse-
quence. After a long examination of the subject in its bibliographic aspect, and having
carefully studied large numbers of the actual organisms, recent and fossil, we find that
they range themselves around six specific centres, which may also be regarded as types
of so many genera ; and with these are allied three other specific forms, not so Rotalian
in aspect ( Tinojoorus , Patellina, and Polytrema).
The protean variability of all the six Rotalian types being great, and isomorphism, or
similarity of form among the varieties and subvarieties of these several specific groups,
being of very frequent occurrence, we still use binomial terms, in a subgeneric sense, for
members of this great group ; and often, in ordinary descriptions, we retain, for the sake
of convenience, binomial appellations (without direct reference to their exact zoological
value) for striking specimens even of varieties and subvarieties. Thus Tru/ncatulina
lobatula is a distinct binomial term for the common variety of Planorbulina farcta first
to be noticed (page 381).
The old name Botalia is retained for one of these six genera; and we arrange the
whole as a subfamily with the appellation of Rotalinae*.
Discorbina Turbo, D'Orb., sp.
Planorbulina farcta, Fichtel and Moll , sp.
Pulvinulina repanda, Fichtel and Moll , sp.
Rotalia Beccarii, Linn ., sp.
Cymbalopora Poyei, D'Orb.. sp.
Calcarina Spengleri, Gmelin , sp.
Tinoporus laevis, Parker and Jones , sp.
Patellina concava, Lam., sp.
Polytrema miniaceum, Esper, sp.
Each of the six Rotaliform genera is represented by one typical species, which carries
with it a large number (from 50 to 200 or 300) of divergent forms, most of them having
* See Carpenter's £ Introd. Eoram.’ Ray Soc. 1862, pp. 198, Ac.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 379
special names, which we must in many instances retain for convenience, though, we refer
them to one or the other of the six species above mentioned.
In nature these Foraminifera are never absolutely strict in their adherence to any one
of the chief varietal forms ; but the latter are serviceable as subspecific centres, around
which may be arranged a large number of modifications, more and more gentle and
mutually confluent ; so that when we speak of Truncatulina lobatula or of Discorbina
vesiculciris (and the same may be said of the varietal groups of any true Foraminiferal
species), we do not mean to say that the specimen which we have before us necessarily
answers exactly to any figure or description in the literature of the subject, but that it
is nearer to some one of the accepted illustrations than to any other. To attempt greater
exactness would be useless; indeed the classification of these little creatures is very
similar to what that of vegetables would be if we had only the separate leaves for our
guides.
From 100 fathoms to shallow water (seaweed-belt, 10 fathoms and less) is the best
home for the Rotaliform Rot almas. Certain varieties of Pulvinulina repanda attain a
good size at 2400 fathoms. The varieties of Planorbulina farcta, also, are not uncom-
mon at very great depths. Piscorbina Turbo , Rotalia Beccarii , Calcarina Spengleri , and
Cymbalopora Poyei avoid great depths (with few exceptions), the best developed specimens
keeping themselves above the Coralline-zone or 25 fathoms.
Planorbulina has a coarsely porous shell (more so than any of its congeners), often of
a relatively large size, consisting of from 15 to 200 or more chambers, with single septa,
and very slight rudiments of the canal-system : it is usually complanate (PI. Mediterrci-
nensis ) and parasitic on sea-weeds and shells ; but many of its varieties are plano-convex
( Truncatulina ), and some become almost subnautiloid (Anomalina). The shell is mostly
smooth ; rarely limbate ( Planulina ) ; and frequently granulate (PI. vulgaris and PI.
larvata) : the aperture varies from an open to a contracted slit, and is often produced
and lipped.
Scheme of the chief members of the Rotaline genus Planorbulina.
Fully developed forms ;
Becoming concentric, with |
alternating chambers <
' • p
built over the apertures of
the penultimate ring.
Intermediate forma.
Quasi-rotalian and
subnautiloid forms. • '
vulgaris, D’Orb. For. Foss. Canar. pi. 2. fig. 30; Carpenter, Introd. For. pi. 13.
figs. 13-15.
Mediterranensis, D’Orb. Modeles, No. 79.
retinaculata, Parker and Jones (sp. nov.) ; Carp. Int. For. p. 209. Plate SIX. fig. 2.
larvata, P. and J. (sp. n.), Ann. Nat. Hist. 3 ser. vol. v. p. 68. Plate SIX. fig. 3.
farcta, Fichtel and Moll, sp. (the type of Planorbulina), Test, Micr. pi. 9. figs. g-i.
lobatula ( Truncatulina ), Walker and Jacob, sp., D’Orbigny’s Modeles, No. 37.
refulgens, Montfort, sp., D’Orbigny’s Modeles, No. 77.
Haidingerii, D’Orb , sp., For. Foss. Yien. pi. 8. figs. 7-9.
TJngeriana, D’Orb., sp., For. Foss. Yien. pi. 8. figs. 16-18.
ammonoides, Reuss, sp., Bohm. Kreid. pi. 8. fig. 53.
reticulata, Czjzek, sp., Hauling. Abhandl. ii. pi. 13. figs. 7-9.
cor onata {Anomalina), Parker and Jones, Ann. Nat. Hist. 2 ser. vol. xix. p. 294,
pi. 10. figs. 15, 16.
Ariminensis ( Planulina ), D’Orb., sp., Modeles, No. 49-.
380
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Figs. 3 to 11 include two striking varieties of Planorbulina far eta, — a type perhaps
the richest of all the Rotalines in modification; and which not only developes the
largest chambers, but produces the largest shells (some with a diameter of a quarter of
an inch, P. vulgaris, D’Orb.). The disk and the chambers are so large in some speci-
mens from tropical seas, that individuals have been mistaken for Polyzoa, and this
mistake has been strengthened by the pouting of the marginal apertures.
Both of the varieties here under consideration, though attaining considerable size, are
arrested and few-chambered varieties. They have attained the simple Rotaline form
without as yet taking on the more characteristic features of the more outspread Planor-
bulince, although their somewhat free mode of growth, the coarseness of their shell-walls,
and their relatively large aperture afford the connecting links to the observer ; more
especially when we find the same shells having the aperture firstly lipped, then pro-
trusive, and gradually (among numbers of individuals) acquiring a neck and distinct
rim. The typical development of this Planorbulina, with a subtubular chief aperture
and supernumerary necked and lipped apertures on the periphery of the shell, is rarely
found in the northern seas ; by far the most common variety is the well-known form,
figs. 3-6, long ago described as Truncatulina lobatula. This, as a rule, grows on a
shell or other substance having a smooth surface, and during the growth of the shell
the little parasitical Foraminifer occasionally becomes more or less imbedded in its
substance. This plano-convex variety represents in the temperate climes the many-
chambered plano-convex Planorbulina Mediterranensis. The latter swarms on sea-
weeds and shells in the shallow water of the Mediterranean ; and it is in company with
it (especially when growing on the larger bivalves, such as Pinna fiabellum ) that PI.
lobatula is seen to take on a wild-growing condition, with subsidiary marginal necks,
becoming PI. farcta and PI. variabilis , without developing nearly so many chambers as
are seen in its associate, although exceeding the latter in size. In tropical and sub-
tropical seas PI. farcta grows on to be the great PI. vulgaris, D’Orb., the arrested
Truncatuline forms being comparatively rare.
In the seas of hot climates a large amount of exogenous granular matter is formed
o o o
on the surface of the shell (as in PL larvata *, Parker and Jones); far different to the
smooth, polished shells in the Mediterranean and northern seas. There is one parasi-
tical form (PI. retinaculataf , Parker and Jones) which, besides being scabrous with gra-
nulation, developes so large a number of peripheral, subsidiary, tubular apertures, con-
necting together, and still keeping apart, the sarcode-chambers, and forming a kind of
irregular network over the surface of the shells on which it grows, like certain Polyzoa,
that the features of this Planorbulina are extremely different from that of its type ; and
it can scarcely be connected with the simple varieties of the species without a know-
ledge of the real relationships of the great and widely extended Rotaline group. The
same structure really exists in the great Pl. vulgaris, D’Orb. For. Canar. pi. 2. fig. 30,
and Carpenter, Introd. For. pl. 13. figs. 13-15 ; but here the connexion of the chambers
* Plate XIX. fig. 3. Ann. Nat. Hist. 3 ser. vol. v. p. 68.
f Plate XIX. fig. 2. Carpenter's Introd. Poram. p. 209.
EOEAMINIEEEA FEOM THE NOETH ATLANTIC AND AECTIC OCEANS.
S81
is masked in some degree" by the obesity of the chambers themselves ; the retinaculate
variety developing smaller and more depressed lobes of sarcode. On Chamci gigas there
is often a wild-growing parasitic Tinoporus isomorphous with PI. retinaculata, but still
larger.
The oldest known Planorbulince are found in the Lias.
Planorbulina farctct, Fichtel and Moll, sp., Yar. ( Truncatulina ) lobatula, Walker and
Jacob, sp. Plate XIV. figs. 3-6 (Arctic); Plate XVI. figs. 18-20 (North Atlantic).
Planorbulina lobatula has been described above to some extent ; we may add that it
is an exceedingly unstable form, even whilst keeping its simple character ; for frequently
it has only half the thickness seen in fig. 5 b, which is an average specimen for such as
live at from 30 to 160 fathoms in the Northern Seas; but at about 60 to 70 fathoms it
frequently assumes a modified condition, taking a high conical shape ( PI . refulgens, Mont-
fort, sp.), its smoothness and polish being much greater than in these flatter forms ; and
the apex of the shell is on the umbilical aspect (as in PI. lobatula) ; the whole coil of
chambers being seen on the base of the shell. PI. lobatula also passes insensibly into
an extremely thin scale-like variety, nearly symmetrical, with limbate septal lines and
square edges, which has been described as Planulina Ariminensis , D’Orb. (Modeles,
No. 49). Other forms gradually lose the plano-convex, or Truncatuline, character ; the
edges become rounded, the primary and succeeding chambers become elevated above
the margin of the shell, which thus grows biconvex or lenticular; for instance, Pla-
norbulina Haidmgerii, D’Orb., sp. (For. Foss. Vien. pi. 8. figs. 7-9), and PL Ungerianci ,
D’Orb., sp. (Ibid. figs. 16-18), common forms at from 60 to 300 fathoms. We here
omit any notice of the intermediate varieties, which have been extensively named as
species.
Like Pulvinulina repanda , as seen in its variety P. Micheliniana (Plate XIV. fig. 16),
the Truncatuline forms of PI. farcta have the spiral arrangement of the chambers
marked on the flat face of the shell ; on the other hand, the plano-convex varieties of
Discorbina Turbo have the umbilical surface flat ; the apex of the cone being formed of
the primordial chamber : an approach to this condition is seen in Plate XIV. figs. 18, 19,
Discorbina obtusa , D’Orb., sp. (For. Foss. Vien. pi. 11. figs. 4-6), a variety of D. Turbo ,
D’Orb., sp. (Modeles, No. 73).
Plate XIV. figs. 3-6 represent specimens of PI. lobatula from the Hunde Islands, in
five dredgings by Dr. P. C. Sutherland (25 to 70 fathoms), where they are very common
and generally of good size; from Baffin’s Bay, at three places; lat. 75° 10' N., long.
60° 12' W., and lat. 76° 30' N., long. 77° 52' W., of middling size and common, and at
lat. 75° N., long. 59° 40' W. (220 fathoms), where they are small and rather common;
and from seven out of the eight dredgings by Mac Andrew and Barrett on the Nor-
wegian coast we have them large and common. We have already indicated that this
variety is world-wide ; fossil, it occurs in the Chalk-marl, Chalk, and many later deposits.
Fig. 6 shows a condition of the parasitic forms of Planorbulina farcta very common,
mdccclxv. 3 f
382
MR. W. K. PARKER AND PROEESSOR T. R. JONES ON SOME
both in this arrested Truncatuline variety and in the outspread Plano rbulince. Two
young individuals, establishing themselves close to each other, grow on until their shells
become blended and confused ; this is still better seen in the many-chambered Planorbu*
linee , two or more of which, growing into each other, form lichen-like patches on shells.
Plate XVI. figs. 18-20 (North Atlantic).
Truncatulina lobatula belongs essentially to shallow waters, and it becomes smaller
when in deeper water than usual (as is the case with the specimens before us), and is
then more compact and neat, takes on a limbation (exogenous edging to the chamber-
walls, fig. 19), and soon approaches the conical and shapely Tr. refulgens , Montfort, sp.
On the eastern marginal plateau of the North Atlantic Truncatulina lobatula is
common and of middle size at from 43 to 78 fathoms, rare and small at 338 fathoms.
It is absent from the abyssal depths. To the north of Newfoundland Bank (“Arctic”
tract) it is rare and small at 145 fathoms, and rare and middle-sized at 740 fathoms.
Planorbulina farcta, Fichtel and Moll, sp., Var. Haidingerii , D’Orbigny, sp. Plate XVI.
figs. 22 a, 22 b (North Atlantic).
This is a variety of Planorbulina farcta near to PI. lobatula , but biconvex and having
more chambers and a more solid and symmetrical make. It is usually larger and more
ventricose than these Atlantic specimens.
This and PI. TIngeriana are two closely allied, compact, and flush-chambered varieties
of PL farcta, more Rotaliform than PL lobatula ,. and inhabiting moderately deep seas..
In the North Atlantic PL Haidingerii is rare and of middle size at 1776 fathoms in the
Abyssal area. It is more abundant in the “ Virginian Province ” on the coast of New
Jersey (see page 333 and Appendix II.). The two are fossil together in Tertiary beds.
PL Haidingerii is world-wide, like the type, and bears the same relation to it that
Eotalia Soldanii does to P. Peccarii, — a rather large and moderately deep-sea variety.
Planorbulina farcta, Fichtel and Moll, sp., Var. TIngeriana, D’Orbigny, sp. Plate XVI.
figs. 23-25 (North Atlantic).
This variety has relatively narrower chambers and more limbation than its congener
Pl. farcta, var. Haidingerii, D’Orb., sp., above-mentioned.
It is widely distributed in the Atlantic. On the marginal plateau off the Irish coast
it is rare and small in the shallow, common and largest in the deeper parts. In the
Abyssal tract (“Celtic”) it is common but small ; and throughout the “Boreal” portion
of that tract (1400-2300 fathoms) it is rare and small. It is figured in Dr. Wallich’S
‘North-Atlantic Sea-bed,’ pl. 6. figs. 20, 21.
Pi TIngeriana is world-wide, like the last ; but, as a weaker and smaller shell, it
takes the place of the type in deepest waters, where also Potalia orbicularis represents
P. Peccarii. Pl. Culter, nov., Plate XIX. fig. 1, is a rare, keeled subvariety, living at
great depths.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
388
Planorbulina farcta, Fichtel and Moll, sp., Yar. Mediterranensis , D’Orbigny. Plate XVI.
fig. 21 (North Atlantic).
This explanate Planorbulina is of small size in the North Atlantic, as usual in North
Temperate seas; it is rare off the Irish coast at 43 fathoms.
It is spiral at first, then excentric, and ultimately concentric ; always orderly in its
growth, with bipolar chambers ; not having exogenous matter, nor a free growth of
marginal apertures. It flourishes in the warmer temperate seas ; is starved in the
British area ; abounds in the Mediterranean and Australian seas ; but in the latter is
less plentiful than PI. vulgaris , with which it is associated. It forms a tiny scale on
flat-fronded sea-weeds, and has a livid pinkish colour, both from its contained sarcode
and from the shell-substance being actually coloured.
Planorbulina farcta, Fichtel and Moll, sp., Var. ( Anomalina ) coronata, Parker and Jones.
Plate XIV. figs. 7-11 (Arctic).
This has been termed Anomalina coronata , Ann. Nat. Hist. 2 ser. vol. xix. p. 294 ; but
it belongs to Planorbulina , and the term Anomalina is not really wanted, however con-
venient it may be as a term for the subsymmetrical or somewhat biconvex arrested
Planorbulince , as Truncatulma indicates the plano-convex few-chambered forms. To
make the so-called genus Anomalina , D’Orbigny took several of the minor forms of Pla-
norbulina farcta, namely those which are somewhat symmetrical and subnautiloid, with
one variety of Discorbina Turbo (A. elegans, Modele, 42).
On taking into consideration the evident passage of form from the plano-convex
(Truncatuline) to the biconcave (Anomaline) condition of the shell, shown by figs. 8,
10, 9, 7, & 11, the observer may at once see the force of the above remarks.
This variety, PI. coronata , has the same kind of shell-substance, thick, subtransparent,
and coarsely perforated, as PI. lobatula ; it has a greater tendency to develope clear,
non-perforate, exogenous shell-matter on both faces of the shell, sometimes hiding the
septal lines ; the pseudopodia chiefly passing from the periphery of the chambers and
through the lacunae in the superadded coating, both on the umbilical (fig. 10) and the
flatter spiral surface (fig. 8). The presence of these lacunae is highly interesting, as
being the first rough outline of the great vascular or interseptal canal-system which
attains such perfection in the highly developed Botalince , Polystomellce, and Nummulina?.
PI. coronata is not so common as PI. lobatula ; it abounds, however, in MacAndrew
and Barrett’s Norway dredgings (at five places) ; and it is abundant at certain places
in the Mediterranean, especially at about 100 fathoms. At such depths it is that
PI. coronata takes the place of PI. lobatula , by living independently and developing its
surfaces more or less freely, whilst but few of the parasitical variety are left on the rare
shells of deep water. PI. coronata has been found abundantly in the North British
seas by Mr. H. B. Brady.
PI. vulgaris also has a subnautiloid form in its young state; and throughout its
growth the chambers are more or less convex both on the attached and the free face.
3 f 2
384
MR. W. Iv. PARKER AND PROFESSOR T. R. JONES ON SOME
Planorbulina vulgaris grows on rough shells (such as Tridacna and IlipflOflus) ; and its
under surface touches but at points, not lying flat (as in PI. Me diterranensis on sea-weed-
fronds, and PI. lobatula on smooth shells and algae).
In the fossil state we have PI. coronata from the Grignon sands (Eocene), of large
size, rivalling in size the Discorbina trochidiformis of that deposit.
Under the names of Botalia , Bosalina , Anomalinci, and Truncatulina , have been
described a great number of subnautiloid forms which are evidently some of them enfee-
blements of PI. coronata (the nearest being Truncatulina vermiculatci , D’Orb. Foram.
Amer. Merid. pi. 6. figs. 1-3), whilst others are either young or arrested modifications
of PI. vulgaris. In deep water Planorbulina scarcely ever takes its true Planorbuline
character ; this many-chambered condition seeming to require sea-weeds or shell-surfaces
for support. Mixed with these, and at still greater depths, we get numbers of small
subsymmetrical nautiloid forms of this species, such as have passed under the names of
Botalia Clementiana , D’Orb., and Botalia ammonoides, Reuss; as well as many other
forms ranging between the latter and Planulina Ariminensis. Planorbulina ammonoides
of the Lias, Gault, and Chalk takes on the symmetrical (subnautiloid) character so
distinctly as to be mistaken for small Nonionince. These small, more or less symmetrical
Planorbulince, so common in some deposits of the Secondary period, are abundant enough
in the existing seas at from 100 to 1000 fathoms, or even more. We may suppose that
the sea-weeds and bivalves of the shallow water of the Secondary period were abundantly
encrusted with Planorbulince as littoral representatives of the deep-sea forms now fossil
in the clays of that period.
Genus Discorbina.
Discorbina Turbo , D’Orbigny (Varieties). Plate XIV. figs. 18-23 (Arctic) ; Plate XVI.
figs. 26-28 (North Atlantic).
Discorbina presents a simple Rotaline form of shell, having from 7 to 30 more or less
vesicular chambers, with double septa when the chambers are discrete, and with rudi-
ments of the canal-system. The shell is coarsely porous (coarser than that of Cymbalo -
pora, and less so than Planorbulina) ; somewhat conical in shape ; the upper side the
thickest ; the margin rather sharp ; but some varieties are complanate with square edges.
The aperture is a large arched slit, usually occluded by an umbilical process or flap,
which is sometimes developed into a subsidiary umbilical chamber ; and the flaps or
chamberlets of the successive chambers give a star-like or Asterigerine aspect in the
umbilicus. Exogenous shell-growth sometimes thickens the septal lines of the spire ;
but it frequently ornaments, and even masks, the umbilical lobes.
The many varieties of this porous and flap-bearing Rotaline species are so intimately
connected one with the other, that the following classification is little more than
suggestive and provisional.
EOEAMINIFEEA FEOM THE NOETH ATLANTIC AND AECTIC OCEANS.
385
Scheme of the arrangement of the chief subspecific forms of Discorbina.
r trochicliformis, Lam., sp., Ann. Mus. viii. pi. 62. fig. 8. Eossilfrom Grignon. Coarsely perfo-
rate, valvular or flapped, valvules marked by a mass of granules. It is an isomorpli of
Polystomella craticulata.
Turbo, D’Orb., sp., Modeles, No. 73. Eossil from Grignon. Coarsely perforate. Valvules
distinct. This is the typical species.
1. Conical. <( rosacea, D’Orb., sp., Modeles, No. 39. Eossil from Bordeaux ( [=Asterigerina Planorbis,
D’Orb.). It is delicately perforate ; valvules distinct.
Pileolus, D’Orb., sp., Eor. Amer. Mer. pi. 1. figs. 15-17. Erom India, Australia, &c., and fossil
from Grignon. Small ; conical or hemispherical : chambers vertical : granulate ornament
in radiating lines. Connecting D. rosacea with D. Parisiensis. It has its extreme flatness
in (Bos.) semistriata, D’Orb., For. Cuba, pi. 3. figs. 15-17.
vesicular is, Lamk. Ann. Mus. viii. pi. 62. fig. 7 ( =(Bot .) Gervillii, D’Orb. Modeles, No. 72).
Erom Australia, and fossil at Grignon. Carpenter, Introd. Eor. pi. 13. figs. 2, 3.
rimosa, Parker and Jones (Carpenter, Introd. Eor. p. 205). Eossil at Grignon: recent from
India to Australia, including Fiji. Plate XIX. fig. 6.
dimidiata, Parker and Jones (Carpenter, Introd. Eor. p. 201. fig. 32, B.). Plano-convex.
Plate XIX. fig. 9.
elegans, D’Orb. Modeles, No. 42. Eossilfrom Bordeaux (—(Rot.) complanata, Eor. Eoss. Yien.
pi. 10. figs. 10—15). Passing insensibly into D. vesicularis.
globularis, D’Orb. Modeles, No. 69 —(Hot.) semiporcita, Egger, sp. Miocene, Germany.
obtusa, D’Orb. For. Foss. Yien. pi. 11. figs. 4-6.
globigerinoicles, Parker and Jones. Extreme of D. vesicularis, running into T). elegans. It is
an isomorph of Cymbalojpora bulloicles, D’Orb. (Bosalina, Cuba, pi. 3. figs. 2-5). Plate
XIX. fig. 7.
Binlchorsti, Eeuss, Sitz. Akad. Wien. xliv. pi. 2. fig. 3. This is an isomorph of Pulvinulina
caracollct, Boem., sp. Limbate.
'Parisiensis, D’Orb., sp., Modeles, No. 38. Eossil at Grignon. Ornamented with granular
lines.
Cora, D’Orb., sp., Eor. Amer. Me'r. pi. 6. figs. 19-21. Complanate, and round-edged ; pro-
bably representing a somewhat starved condition.
Berthelotiana, D’Orb., sp., Eor. Canaries, pi. 1. figs. 28-30.
biconcava, Parker and Jones (Carpenter, Introd. Eoram. p. 201. fig. 32, G). Complanate,
with raised square edges. Plate XIX. fig. 10.
The oldest known are Discorbina Turbo and I). Binlchorsti, both in the Maestricht
Chalk.
Discorbina Turbo , Var. rosacea , D’Orbigny, sp. Plate XVI. hgs. 28 a, 28 b (North
Atlantic).
Discorbina rosacea , D’Orb., sp. (Modeles, No. 39), has an exquisitely sculptured, and
more delicately porous shell than usual (the margin only may be porous) ; its astral flaps
form sometimes a secondary system of chambers. These characters are developed largely
in D. Turbo , D’Orb., sp., the type of the whole group, from which this flat variety has
no essential distinction. D. rosacea is rather common and of the middle size on the
Irish plateau at 43 fathoms.
2. Vesicular:
valves feeble in
the feeble vesi-
cular forms,
especially in ^
globidaris and
its poor rela-
tions.
3. Outspread
(more or less
complanate) : j
valves feeble in
the small out-
spread forms.
386
ME. W. K. PAEIvEE AND PEOEESSOE T. E. JONES ON SOME
D’Orbigny’s Asterigerina Plcmorbis (For. Foss. Vieii. pi. 11. figs. 1-3) supplies a very-
good representation of this elegant form: see also Williamson’s Monogr. pi. 4.
figs. 109-111 ( Rotalina Mamilla ), and his pi. 4. fig. 112, and pi. 5. fig. 113 ( B . ochracea).
The most exquisite specimens of this variety are from San Domingo (fossil), where it
abounds in the Miocene beds. It is always small ; but is larger and coarse on the
Australian shores, passing insensibly into D. Turbo. It is common in the Grignon
Tertiary deposits, rare in our Crag, and world-wide in the present seas.
Discorbina Turbo , D’Orbigny, sp., Var. vesicularis, Lam., sp., Subvar. globularis,
D’Orbigny, sp. Plate XIY. figs. 20-23 (Arctic).
This small vesicular form of 1). Turbo , D’Orb., sp., is I). globularis , D’Orb., sp.
(Modele, No. 69), from the Atlantic; and the same as Egger’s Bosalina semipunctata,
Neues Jahrb. 1857, pi. 4. figs. 1-3. It is smaller than I). vesicularis , Lamarck, sp.
(= 1 ). Gervillii, D’Orb., sp., Modeles, No. 72), and has fewer chambers.
It is a world-wide form in shallow water and down to 70 fathoms, at which depth,
west of the Bay of Biscay, it abounds ; it is, however, flatter here than when nearer the
shore. In deeper water it becomes D. Berthelotiana and 1). rosacea , D’Orb., spp.
At the Hunde Islands (Sutherland’s Soundings) it is large and rather common at
from 30-40 fathoms; and middle-sized and common at from 50-70.
Discorbina Turbo , D’Orbigny, sp., Var. vesicularis , Lamarck, sp., Subvar. obtusa, D’Or-
bigny, sp. Plate XIY. figs. 18, 19 (Arctic).
Discorbina presents a simple Botaline form of shell, usually having more or less vesi-
cular chambers, with porous walls, and with the septal apertures in many cases guarded
by flaps or plates, which sometimes form small secondary umbilical chambers.
The specimen here figured is near to D. globularis , D’Orb., sp. (Modele, No. 69), but
may either be regarded as a swollen condition of the beautiful D. Parisiensis, D’Orb., sp.
(Modele, No. 38), or, rather, as D. vesicularis with the style of ornament characteristic
of D. Parisiensis. The nearest approach to it among published figures is made by D.
obtusa , D’Orb., sp., For. Foss. Yien. pi. 11. figs. 4-6. The coarseness of its pores, its few
and subvesicular chambers, its large central chamber, and its peculiar ornamentation,
are the chief characters of the variety before us. In the Arctic specimens the orna-
ment appears as obscure, irregularly radiating, minutely granular lines on the lower face
(not well shown in the figure] ; in D. Parisiensis the under surface has an exquisite
sculpturing of minutely granulate lines or ridges ; D’Orbigny’s D. obtusa has a granular
ornament in radiating'lines [not well shown in the figure]. D. globigerinoides, Plate
XIX. fig. 7, a new variety of D. Turbo, also has this kind of ornament, being thickly
covered on the septal plane with sinuous exogenous rugae, having large pores opening
out of them, thus presenting a rudiment of the canal-system.
At the Hunde Islands, D. obtusa is large and rare at 28 to 30 fathoms; large and
rather common at 30 to 40 ; and large and common at 60 to 70 fathoms.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
387
Discorbina Turbo, D’Orbigny, sp., Var. Parisiensis, D’Orbigny, sp., Subvar. Berthelotiana,
D’Orbigny, sp. Plate XVI. figs. 26, 27 (North Atlantic).
Discorbina Berthelotiana, D’Orb., sp. (For. Canar. pi. 1. figs. 28-30), may be regarded
either as a compressed and more or less limbate form of D. globularis, D’Orb., sp., or,
rather, as intermediate to D. globularis , D’Orb., sp., and D. Parisiensis , D’Orb., sp. (Mo-
deles, No. 38), but without the ornamentation below. It is generally small ; usually
showing an umbilical flap or angle ; but in fig. 27 a granule represents it. This variety
makes a near approach to the strongly limbate Discorbina Binkhorsti , Reuss, sp. (Sitz.
Akad. Wien. 1861, vol. xliv. pi. 2. fig. 3), of the Maestricht Chalk; and, though it
resembles some of the margined Grlobigerinoe of the Chalk, it has no relationship with
them.
Our fig. 26 is much more limbate than the specimen figured by D’Orbigny ; but they
are essentially the same.
D. Berthelotiana occurs on the marginal plateau off Ireland, small and rather common
at 78 fathoms, and small and rare at 43 fathoms.
Genus Rotalia.
Botalia Beccarii , Linn., sp. (Varieties). Plate XVI. figs. 29-34 (North Atlantic).
Botalia has a finely porous shell (coarser than that of Pulvinulina and finer than Cal-
carina) ; biconvex (lowest side thickest), with round margin ; made up of from thirteen
to forty chambers, with double septa ; canal-system present. Septal lines and umbilicus
often beaded with exogenous granules, sometimes to a great extent. Aperture a slit
(occasionally subdivided), sometimes notched at the umbilical margin of the septal
plane, as in Pulvinulina, Discorbina, and arrested Planorbulinoe. Shell rarely prickly ;
occasionally Asterigerine ; generally small, compared with most other Rotalines ; or,
rather, it does not attain to quite as great a size.
Scheme of the chief subspecies of Rotalia.
Rotalia Schroeteriana, Parker and Jones. See Carpenter, Introd. For. pi. 13. figs. 7-9.
omata, D’Orb., sp., For. Amer. Mer. pi. 1. figs. 18-20.
— — craticulata, Parker and Jones. Plate XIX. fig. 12. (Fiji.) .
annectens, Parker and Jones. Plate XIX. fig. 11. (Hong Kong.)
pulcliella, D’Orb., sp., For. Cuba, pi. 5. figs. 16-18. See Carpenter, Introd. For. p. 213.
dentata, Parker and Jones. Plate XIX. fig. 13. (Bombay Harbour.)
Beccabii, Linn. D’Orbigny’s Modeles, No. 74. This is the Type species.
• ammoniformis, D'Orb. Ann. Sci. Nat. vol. vii. p. 276. No. 53. (After Soldani.)
lobata, D’Orb., sp., For. Cuba, pi. 5. figs. 19-21. See Carpenter, Introd. For. p. 213.
carinata, D’Orb., sp., For. Cuba, pi. 5. fig. 25, pi. 6. figs. 1, 2.
Soldanii, D’Orb. Modeles, No. 36.
umbilicata, D’Orb. Ann. Nat. Sci. vol. vii. p. 278. No. -4, and Mem, Soc. Geol. Fr. vol. iv. pi. 3. figs. 4—6.
orbicularis, D’Orb. Modeles,, No. 13.
388
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Eotalia affords ns a good example of the parallelism that may be traced between the
members of one and another Foraminiferal species (just as occurs in other natural
groups). Thus, contrasted with Polystomella , we have an interesting series of repre-
sentative forms.
Parallelism of Eotalia Beccarii and Polystomella crispa.
Varieties of Eotalia Beccarii.
Eotalia Schrceteriana, Parlcer and Jones.
Beccarii, Linn, (large typical form).
ammoniformis, IP Orb. (flat var. Bimini).
Beccarii, Linn, (small smooth var.).
dentata, Parlcer and Jones.
Soldanii, IP Orb.
orbicularis, IP Orb.
(Calcarina) pulchella, IP Orb.
(Asterigerina) lobata, IP Orb.
Varieties of Polystomella crispa.
Polystomella craticulata, Ficlitel and Moll.
crispa, Linn.
macella, Ficlitel and Moll.
striato-punctata, Ficlitel and Moll.
strigilata (var. /3), Ficlitel and Moll.
■ (Nonionina) asterizans, Ficlitel and Moll.
(Nonionina) pompilioides, Ficlitel and Moll.
unguiculata, Gmel.
(Nonionina) stelligera, D'Orb.
The nearness of the two specific groups is also seen in our new Eotalia craticulata
(Plate XIX. fig. 12) being separable from Polystomella crispa chiefly by its want of
symmetry ; and, further, E. Schrceteriana passes into E. craticulata by a greater diffe-
rentiation of the canal-system, which approaches its most perfect condition in the
higher Polystomella.
Eotalia Beccarii , Linn., sp. Plate XVI. figs. 29, 30 (North Atlantic).
Figs. 29 & 30 present a strongly granular condition on the lower surface, and may be
said to be passing into the smaller varieties that belong to deep water ; indeed, they are
intermediate between the common E. Beccarii of shallow water and the variety known
as E. Soldanii , D’Orb. (Modeles, No. 36), that inhabits deep water. With flattened and
adpressed chambers on the upper side, and without granules on the lower, figs. 29 & 30
would be E. Soldanii ; such modifications are common. E. Beccarii passes into E. Sol-
danii in deep seas everywhere; but in hot seas it also passes into the large, conical,
craticulate form (E. Schrceteriana , Parker and Jones) with pseudopodial passages, as in
Polystomella.
Both in its estuarine and its abyssal varieties E. Beccarii is feeble, being delicate in
shell and small in size. Its smallest and most abyssal variety is E. orbicularis, D’Orb.
(fig. 34), which is not abundant. In about 100 fathoms E. Soldanii , with a diameter
three times as great as that of E. orbicularis , is abundant enough, and is of stronger
make. The shell becomes larger, more vesicular and more granular in the best habitat
of E. Beccarii (20 to 40 fathoms in warm seas) ; and in shallow waters it is smaller (of
the size of E. Soldanii ), less strong in its structure, even more vesicular, and extremely
abundant (even in some brackish waters).
Eotalia Beccarii from the Lido (Venice) and Eimini, both on the Adriatic, is very
smooth and complanate (although large and well-developed), compared with specimens
FOEAMINIFEEA FEOM THE NOETH ATLANTIC AND AECTIC OCEANS. 389
in the same latitude on the western shores of Italy and in fossil deposits (formed in
shallow water) near Sienna ; whilst the same species in the south-eastern parts of the
Mediterranean has much thicker and more granular varieties than those in the west of
Italy, and becomes very like the great Botalia Schroeteriana, Parker and Jones (Ann.
Nat. Hist. 3 ser. vol. v. p. 68, and Carpenter’s ‘ Introd. Foram.’ p. 213, pi. 13. tigs. 7-9).
As we approach our own shores from the Mediterranean area, Botalia Beccarii
becomes gradually smaller but is still numerous : to the north it deteriorates more and
more.
Botalia Beccarii is rare and small at 78 fathoms on the Irish marginal plateau.
Botalia Beccarii , Linn., sp., Var. Soldanii , D’Orbigny, sp. Plate XVI. tigs. 31-33
(North Atlantic).
This may be described as Botalia Beccarii becoming flush-chambered, conical (flat
above), with a strong shell: in this form it inhabits deep water, about 100 fathoms
(from 50 to 300 fathoms). D’Orbigny illustrated B. Soldanii by his Model, No. 36.
It is the isomorph of Pulvinulina Micheliniana and of Planorbulina ( Truncatulina )
refulgens , which are the deep-sea forms of their respective species.
B. Soldanii is rare and small at 43 fathoms, rather rare and middle-sized at 223
fathoms, and common and middle-sized at 415 fathoms, on the western plateau. It is
rare and small at 1776, 2035, 2050, and 2350 fathoms in the abyssal area.
It is very common in the Mediterranean (at 100 fathoms), and fossil in the Sub-
apennine clays. Generally it is not so flat at the top as our figured specimens are ;
but the upper faces of the cells are convex and separated by sulci (see D’Orbigny’s
Model).
Botalia Beccarii , Linn., sp., Var. orbicularis, D’Orbigny, sp. Plate XVI. fig. 34
(North Atlantic).
This extremely delicate and minute abyssal variety of B. Beccarii is but little removed
from B. Soldanii ; but it is smaller, and has its upper face still flatter and smoother
than in B. Soldanii. It is in shape half an oblate spheroid, having the upper side flat,
the lower forming a low rounded cone. It may be said to be the starved abyssal variety
of its species. It occurs, but sparsely, in deep-sea soundings in all latitudes — tropical to
north-temperate ; and it has been brought up from even 1000 fathoms and more, retain-
ing its exquisite salmon-coloured sarcode.
D’Orbigny got his specimen, illustrated by Model No. 13, from the Adriatic.
The best localities for it are the Red Sea, where it has degenerated from B. ornata
and B. Schroeteriana , and in the Mediterranean area, where it is ancestrally related to
B. Beccarii. It becomes extremely small, one of the smallest even among starved Fora-
minifera; and, as such, is very rare at Shetland and in the Irish Sea (Brady).
In the abyssal area of the Atlantic it occurs very rare and very small at 1950 fathoms.
3 G
MDCCCLXV.
390
MR. W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
Genus Pulvinulina.
Pulvinulina repanda , Fichtel and Moll, sp. (Varieties). Plate XIV. figs. 12-17 (Arctic);
Plate XVI. figs. 35-51 (North Atlantic).
Pulvinulina repanda is the type of a group of Botalince, as above mentioned (page 378),
of which we have here five varieties. Each of these belongs to a separate subspecific
group ; and, though they are few among many, yet they are of considerable importance
in their several sub-groups, and may well serve as a basis for a general account of Pul-
vinulina repanda specifically considered.
P. repanda , when well developed, has its shell-structure dense and minutely perfo-
rated, compared with that of other Potalinm ; more so than Potalia Beccarii and Calca-
rina Spengleri , and much more so than Piscorbina Turbo and Planorbulina farcta. In
the delicacy of its tubuli (almost as fine as those of dentine) it rivals Nummulina and
Heterostegina ; whilst the loose coarse structure of some of the larger specimens of Pis-
corbina and Planorbulina remind us of that of the Echinoderm and Madrepore.
Pulvinulina is most apt to take on an extra growth of shell-matter on the septal lines
and the margins of the shell (limbation), and among its very numerous varieties there
are many that are strongly limbate, and are more or less compact in growth ; whilst other
varieties are delicate, and become thin, outspread, Spirilline, and vermiculate. The
shell has from seven to nearly thirty cells, with single septa and but little trace of the
canal-system : it is rarely prickly ; the umbilicus is often ornamented by granules, or by
a boss, or a star of shelly matter ; the aperture is a large fissure, often arched, and
notched ; and the septal face often bears numerous coarse subsidiary perforations. The
shell is usually biconvex ; the upper side the thickest ; the margin more or less angular
and subcarinate ; some varieties are complanate, with square edges, as in Roemer’s figures
of P. caracolla and its allies from the ITils Clay and the Gault ; similar forms to these
occur also in the Kimmeridge Clay of Kimmeridge.
We may divide the Pulvinulinoe into five groups, as follows: —
First Group, or that including P. repanda proper. — In its typical form P. repanda is a
spiral coil of chambers, forming a low conical shell, showing the spire, with a more or
less open umbilicus ; some of the older chambers usually having limbate septa. The
shell has generally an irregularly oblong form ; the chambers rarely forming a symme-
trical disk, never flush at the edges, but set on loosely, and usually increasing in size in
a somewhat rapid ratio ; they present often a curved or sickle-shaped outline both above
and below, or are curved and narrow above, broad and irregularly triangular below.
The umbilical portions of the chambers are generally very attenuate, fitting neatly as
they converge to the centre. Occasionally these lobes are separated by narrow chinks ;
sometimes they are deficient, leaving a large umbilical gap. The septal face is either
gently convex, or flat ; in the latter case it is perforated with proportionally large holes.
The aperture is a large arched slit, occasionally notched at its upper margin. Granulate
ornament is not uncommon on the upper surface of the shell ; below, exogenous matter
EOEAMINIEEEA EEOM THE NOETH ATLANTIC AND AECTIC OCEANS.
191
may either fill the umbilical cavity, or affect the borders of the umbilical lobes, even to
their union by a bridge-like growth. Limbation is seldom absent from the border of the
shell; frequent on the older part of the spire; and not uncommon with the later
chambers. Figs. 101-103 in Professor Williamson’s ‘Monograph of British Recent
Foraminifera’ represent a common condition of this typical form.
The members of Group No. 1 inhabit depths of about 10 to 100 fathoms. The vari-
eties affecting the shallow water are less neat in their make than those of greater depths.
Second Group, characterized by P. Auricula and P. oblonga. — In this group the shells
are far more oblong in shape, from the very rapid increase of size of the chambers ; and,
as a rule, they are much more delicate and frail than the foregoing, although some small
deep-sea varieties of this subtype are unusually dense. The septa and borders are rarely
limbate. The septal face of the last chamber is usually drawn out and inflated, but
narrow, and, by an umbilical process, overlaps the alar terminations of the older
chambers. This feature has caused D’Orbigny to class several varieties of this subtype
as species of his genus Valvulina. In some cases a portion of the septal face near the
umbilicus is flattened and pertused ; and this feature is usually associated with some
degree of limbation of the upper septal lines. The whole of the septal face is flattened
and coarsely perforate in certain forms lying between P. Auricula and P. repanda. The
aperture is similar to that in Group No. 1 ; but occasionally there is a large subsidiary
notch. The umbilical lobes terminate in a similar manner to what obtains in the typical
group ; and the umbilicus, as in the former, may either be closed, by the meeting of the
lobes, or remain slightly open, or be largely excavate. The varieties in which the last-
named feature occurs are small deep-sea forms, having dense shell-tissue, a flattened
hispid upper surface, with flush chambers ; the under surface being gently convex and
highly polished.
As a rule, in each of the subgroups of P. repanda , here described, the thick-set vari-
eties are those that inhabit deep water.
The members of the Group No. 2 have their best home at 50 to 70 fathoms ; but they
range from shallow water (algal zone) to 500 fathoms or more.
The Third Group, including P. Menardii. — This is an assemblage of closely related
varieties, differing however considerably in feature. Some are very flat and scale-like,
some conical, some biconvex. The flat forms have usually a somewhat oblong outline ;
but the members of this group are mostly circular, with indented septal lines ; the
chambers are sometimes triangular on both surfaces ; though sometimes narrow and
curved, or oblong, or even square above and more or less triangular below. P. Menardii
and its nearest allies are margined and limbate on the upper surface, and often granular,
scabrous, or hispid. These features are less striking in other varieties which pass gra-
dually into feebly marked, smooth, thick, small, untypical forms. The septal face is still
large in this group, gently convex or flat ; sometimes sinking in at a spot near the aper-
ture, which is often boldly notched. The chambers of these shells are fewer than in
the “repanda-” or “type-group”; but in the better developed specimens they have the
3 g 2
392
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
same rapid increase of size, with the same neat convergence of the umbilical lobes ; the
lines between them, however, being usually straighten The conditions of the umbilicus
resemble those of the typical group ; but the contracted form of the shell, in certain
varieties, raises up the umbilical portions of the chambers into the apex of a cone, the
base of which is the neat and almost flat spiral surface.
The members of this group, all of which are mutual companions, are obtained from
abyssal depths, 100 to 2700 fathoms.
Fourth Group, characterized by P. Schreibersii. — These shells have more numerous
chambers than we find in the foregoing groups, nor do they enlarge with age so rapidly.
The lower surface shows but few chambers (5-11), in contrast with those seen above
(15-30) ; whilst in groups Nos. 1-3, all except the four or five earliest chambers are seen
on the umbilical as well as on the spiral surface, on account of the spire being subdis-
coidal, whilst in P. Schreibersii and its allies the spire is helical or subturreted. There
is also a greater tendency to limbation (exogenous shell-growth on the septal lines and
the margin), especially about the umbilicus, where a knob, a group of granules, or a
star-like ornament is not unusual ; hence this may be termed the “ stellar ” group.
These, moderately deep-sea forms for the most part, have often the thickest shells of any
among the subtypes, especially P. Schreibersii itself, as found in the muds of the Gulf
of Suez at about 40 fathoms. This group has a very extensive bathymetrical range.
Fifth Group, with P. elegans as the leading form. — This is closely allied to the last
group in its general features, and may be said to represent a further development of its
peculiarities. We have here a series of neat, compact, more or less biconvex, and for
the most part limbate Pulvinulince. The limbation is less constant on the upper (spiral)
than on the lower surface, on which latter a symmetrical wheel-like ornament is often
found, imitating such as occurs on some nautiloid Cristellarice. On the upper surface
the limbation is sometimes strongly developed, both on the septal lines and the margin,
and in some cases (P. D'Orbignii , Rcemer, and P. ornata , Roemer) masks the spire
altogether. On the other hand the limbation may be but slight ; and in P. Cordieriana ,
excepting as regards the umbilical boss, it is nearly obsolete. Some subvarieties of P.
elegans itself appear with little exogenous or limbate ornament.
In this group the shell is polished to the utmost ; and in the same gatherings from
very deep water P. Menardii will be in its roughest condition and P. elegans will be
highly enamelled and glistening. It is always neat and nautiloid. The group ranges
from 70 to 1000 fathoms.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 393
1st Group.
The type or
repauda group.
10-100 fathoms.
2nd Group.
Auricula or
oblonga group.
10-500 fathoms
(70 fathoms best).
3rd Group.
Menardii group,
Abyssal group.
100-2700 fathoms.
4th Group.
Schreibersii group,
Stellar group.
30-2700 fathoms.
5th Group.
Elegans group,
strongly limbate.
70-1000 fathoms.
Scheme of the chief Members of the Genus Pulvinulina.
f vermiculata, D’Orb. (after Soldani). Carpenter, Introd. pi. 13. figs. 4-6.
sinuata, Fichtel and Moll, sp., Test. Micros, pi. 10. figs. a-c.
repanda, Fichtel and Moll, sp., Test. Micr. pi. 3. figs. a-cl. (The type of Pulvinulim.)
i pulchella , D’Orb., sp., Modeles, No. 71.
' punctulata, D’Orb., sp., Modeles, No. 12.
Caribcea, D’Orb., sp., For. Cuba, pi. 5. figs. 1-3.
Boueana, D’Orb., sp., For. Foss. Yien. pi. 7. figs. 25-27.
^ concentrica , Parker and Jones; Soldani, Test. i. pi. 37. fig. B.
r Auricula, Fichtel and Moll, sp., pi. 20. figs. a-f.
Sagra, D’Orb., sp.. For. Cuba, pi. 5. figs 13-15.
oblonga, Williamson, sp., Monogr. pi. 4. figs. 98—100.
Brongniartii, D’Orb., sp., For. Foss. Yien. pi. 8. figs. 22-24.
Hauerii, D’Orb., sp., For. Foss. Yien. pi. 7. figs. 22-24.
contraria, Reuss, sp., Zeitsch. Deutsch.' Geol. Ges. iii. pi. 5. fig. 37, a, b, c.
^ deformis, D’Orb., sp., For. Cuba, pi. 4. figs. 9-11.
incequalis, D’Orb., sp. ( Valvulina), For. Amer. Mer. pi. 7. figs. 10-12.
oblonga, D’Orb., sp. ( Valvulina ), For. Canar. pi. 1. figs. 40-42.
excavata, D’Orb., sp. ( Valvulina ), For. Canar. pi. 1. figs. 43-45.
scaphoidea, Reuss, sp., Neue For. Oester. Tert. pi. 47. fig. 3, a, b, b'.
^ Auris , D’Orb., sp. ( Valvulina ), For. Canar. pi. 2. figs. 15-17.
''Menardii, D’Orb., sp., Modeles, No. 10.
cultrata, D’Orb., sp., For. Foss. Cuba, pi. 5. figs. 7-9.
umbonata, Reuss, sp., Zeitschr. d. g. G. iii. pi. 5. fig. 35, a-c.
crassa, D’Orb., sp., For. Craie bl. Fr. pi. 3. figs. 7, 8.
dubia, D’Orb., sp.. For. Cuba, pi. 2. figs. 29, 30, pi. 3. fig. 1.
^ Canariensis, D’Orb., sp., For. Canar. pi. 1. figs. 34—36.
pauper ata, Parker and Jones, nov. sp. Plate XYI. figs. 50, 51.
Micheliniana, D’Orb., sp., For. Craie bl. Fr. pi. 3. figs. 1-3.
nitida, Reuss, sp., Bohm. Kreid. pi. 12. fig. 20, a, b.
<.truncatulinoides, D’Orb., sp., For. Canar. pi. 2. figs. 25-27.
f Schreibersii, D’Orb., sp., For. Foss. Yien. pi. 8. figs. 4—6.
Antillarum, D’Orb., sp., For. Cuba, pi. 5. figs. 4-6.
concava, Reuss, sp., For. Ostalp. Kreid. pi. 26. fig. 3, a-c.
Badensis, Czk., sp., Fos. For. Wien, pi. 13. fig. 1-3.
Peruvians, D’Orb., sp., For. Am. Mer. pi. 2. figs. 3-5.
^ Karsteni, Reuss, sp., Zeit. d. g. G. vii. pi. 9. fig. 6, a-c.
squamiformis, Reuss, sp.. For. Kreid. Ostalp. pi. 26. fig. 2, a-c.
I Alvarezii, D’Orb., sp., For. Am. Mer. pi. 1. fig. 21, pi. 2. figs. 1, 2.
j spinimargo, Reuss, sp., Neue For. Oester. Tert. pi. 47. fig. 1, a, b.
v_ Patagonica, D’Orb., sp., For. Amer. Mer. pi. 2. figs. 6-8.
r elegans, D’Orb., sp., Ann. Sc. Nat. p. 276, No. 54.
caracolla, Nils., sp., Roemer’s Nord-Deuts. Kreid. pi. 15. fig. 22.
Partschiana, D’Orb., sp., For. Foss. Yienn. pi. 8. figs. 1-3.
Berthelotiana, D’Orb., sp., For. Canar. pi. 1. figs. 31-33.
( Cordieriana, D’Orb., sp., For. Craie bl. Paris, pi. 3. figs. 9-11.
I ornata, Nils., sp., Roemer’s Nordd. Kr. pi. 15. fig. 25.
D’Orbignii, Nils., sp., Roemer’s Nordd. Kr. pi. 15. fig. 24.
J stelligera, Reuss, sp., For. Kreid. Ostalp. pi. 25. fig. 15, a-c.
L Partschiana, D’Orb. sp., var., Borneman, Fauna Septar.-Thones Hermsd. pi. 16. fig. 6, a-c.
394
MB, W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
Pulvinulina repanda , Fichtel and Moll, sp., Yar. punctulata , D’Orbigny,*sp. Plate XIY.
figs. 12, 13 (Arctic).
Though flatter, this is essentially the same as Pulvinulina punctulata, D’Orb., sp.,
Modele, No. 12. When smaller, more limbate, and less compact in growth, it passes
into more ordinary varieties, such as P. repanda , Fichtel and Moll, sp. (Rotalina conca-
merata, Williamson, Monogr. pi. 4. figs. 101-103).
In our former description of the Norwegian Foraminifera, we mistook this large variety
for a large growth of Biscorbina vesicular is, Lam., sp. It is represented, in Messrs.
Mac Andrew and Barrett’s dredgings, by one specimen from sand at West Fiord
(Nordland) from 60 fathoms depth, and eight specimens that occurred on sponge from
100 fathoms at Yigten Island, Inner Passage (Drontheim).
It lives also in the Adriatic (D’Orbigny) and at Orotava (Canaries) ; and is abundant
and large off Sicily, and in the Levant, and in many other parts of the world at mode-
rate depths. The huge specimens from the Crag, larger than our Norwegian specimens,
lean more to the looser and few-celled type figured by Williamson.
Pulvinulina repanda , Fichtel and Moll., Var. Menardii , D’Orbigny, sp. Plate XVI.
figs. 35-37 (North Atlantic).
Pulvinulina Menardii , D’Orb., Modeles, No. 10, is a deep-sea form of P. repanda ; it
is in best condition at from 100-500 fathoms, but lives well at even three miles depth ;
in shallow water (algal belt) it becomes either conus-shaped, or much depressed with a
large keel (P. pauperata, Parker and Jones, Plate XVI. figs. 50, 51); whilst P. repanda
(the type) becomes vermiculate, abounding in the Mediterranean as Pulvinulina vermi-
culata , D’Orb., sp. ( Planorbulina vermiculata, D’Orb., Ann. Sc. vii. p. 280, No. 3; after
Soldani). At from about 30-100 fathoms in the Mediterranean the typical P. repanda
abounds ; and in the same sea the obtusely conical P. Micheliniana represents the species
abundantly at from 500—1500 fathoms on muddy tracts, whilst the flatter form (P. Me-
nardii) common in the depths of the great oceans seems to be wanting there. P. Miche-
liniana is also potent in the Arctic seas and North Atlantic; and is fossil in great
numbers in the Chalk.
P. Menardii is generally limbate and granulo-aciculate ; the specimens before us are
more or less limbate and have roughish shells. They are not numerous, nor have they
attained the fulness of size and beauty that belong to the species in lower latitudes ; the
further north, the poorer they are ; for those in the Mid-Atlantic (Dayman) are generally
somewhat larger than those in the North Atlantic (Wallich’s Collection) ; and this is the
case with other species and varieties. In the Atlantic the proportion of Pulvinulince to
the Foraminiferal fauna is perhaps not ygfh of what will be found in the deep water of
tropical and subtropical seas.
In the North Atlantic Pulvinulina Menardii is widely distributed. On the marginal
plateau off Ireland it is rare and small in the shallow, less rare and larger in the deeper
part. It is of middle size and common in the “Celtic” portion, and rather rare
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
395
throughout the “ Boreal” portion of the abyssal tract (1400-2300 fathoms) ; and neither
large nor common at 329 fathoms north of Newfoundland Bank. Mr. Brady has some
fine specimens from the Irish Sea.
Pulvinulina repanda, Fichtel and Moll, sp., Var. Menardii, D’Orbigny, sp., Subvar.
Canariensis, D’Orbigny, sp. Plate XVI. fig. 47-49 (North Atlantic).
Pulvinulina Canariensis, D’Orb., For. Canar. pi. 1. figs. 34-36, is a dwarf form of
P. Menardii, common but distinct among the larger specimens in deep water, and widely
distributed from the north to the Tropics. It is more attenuate than well-grown
specimens of the subtype (P. Menardii), and usually is very imperfectly limbate.
D’Orbigny’s figure has a limbate upper surface, and the mouth more patent on the
lower plane than in our specimen : but these modifications are of continual occurrence.
P. Canariensis may be said to be a starved form among wTell-fed ones (as happens with
Globigerince and many other Foraminifera) ; yet it is well to keep it apart with a name,
as, should it occur without P. Menardii, it would bespeak an unfavourable habitat.
In the North Atlantic Pulvinulina Canariensis is wide-spread. On the eastern marginal
plateau it is common and small at 78 fathoms, rare and small at 338 fathoms, and rare
and middle-sized at 415 fathoms. In the “Celtic” abyssal tract it is rather common;
throughout the “Boreal” portion also (1400-2300 fathoms) it is rather common, but
smaller. North of the Bank, at 161 fathoms, and in Trinity Bay, it is rare and small.
Pulvinulina repanda, Fichtel and Moll, sp., Var. Menardii, D’Orb. sp., Subvar. pauperata,
nov. Plate XVI. figs. 50, 51 a, 51 b (North Atlantic).
Pulvinulina pauperata is rare, usually small, and nearly symmetrical ; found at
great depths (2000 fathoms) in both high and low latitudes, and is often much larger in
the latter than in the former. It presents a feeble, and, as it were, accidental condition,
in which the thin film of sarcode surrounding the few feebly marked chambers has been
calcified beyond their verge. Though it is very small here, we have seen this variety
(from subtropical seas) as large as the largest P. Menardii. In tropical seas (Tropical
Atlantic and Indian Ocean) it is large but rare.
This variety occurs in company with P. Menardii and P. Canariensis, which are found
taking on a margined condition, with feebly developed chambers, thus connecting the
depauperated variety under notice with themselves. Comparing this deep-sea attenu-
ated form with those of shallow water, we see that the latter become vermiculate, losing
the power of forming separate chambers.
P. pauperata is rare in the North Atlantic (the figured specimens are all we met with) ;
in the “Boreal” tract, towards Newfoundland Bank it is middle-sized at 1450 fathoms;
and in the Abyssal “ Celtic” tract it is small.
396
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Pulvinulina repanda , Fichtel and Moll, sp., Var. Menardii, D’Qrbigny, sp., Subvar. Miche -
liniana, D’Orbigny, sp. Plate XIV. fig. 16 (Arctic) ; Plate XVI. figs. 41-43
(North Atlantic).
This small compact conical Pulvinulina occurs in deep water. Its deepest known
habitat is at 2700 fathoms (South Atlantic). It is very common in the North Atlantic.
In the Mediterranean it flourishes at 400-500 fathoms on muddy bottoms, being larger
there than our figured specimens ; it then takes the place of P. Menardii. In shallow
vrater it degenerates into bizarre varieties.
P. Micheliniana abounds fossil in the Chalk and Gault, and was first described by
D’Orbigny in his Memoir on the Foraminifera of the White Chalk of Paris, Mem. Soc.
Geol. de France, vol. iv. pi. 3. figs. 1-3, together with another closely allied variety of
P. Menardii (P. crassa, D’Orb., sp., loc. cit. figs. 7-8); as well as a third variety
(P. Cordieriana , D’Orb., loc. cit. figs. 9-11), a member of the P. elegans group of P. re-
panda.
At the Flunde Islands this usually deep-sea form, P. Micheliniana , is represented by
rare and small individuals at 25-30 fathoms.
Plate XVI. figs. 41-43 (North Atlantic).
From the Arctic Ocean we had but very few specimens of P. Micheliniana , owing to
the paucity of deep-sea soundings. In the North Atlantic it is very common; and
generally very rough or scabrous in its shell-tissue ; in fact it may be said to be here
P. truncatulinoides, D’Orb., sp. (For. Canar. pi. 2. figs. 25-27), and the two forms are
scarcely worth separating by distinct names.
On the Irish marginal plateau it is rare and small in the shallow, rather common and
large in the deep parts. In the “ Celtic” abyssal depths it is common and rather large ;
but in the “Boreal” tract (at upwards of 2000 fathoms) it is smaller and rarer; and
nearer to the Bank it is rare and small at 1450 fathoms.
Pulvinulina repanda , Fichtel and Moll, sp., Var. Karsteni , Iteuss, sp. Plate XIV. figs. 14,
15, & 17 (Arctic); Plate XV. figs. 38-40 (North Atlantic).
This is a neat, many-chambered, moderately conical variety of P. repanda , with some
degree of limbation bordering the chambers, especially beneath, where a wheel-like
system of exogenous shell-matter characterizes the shell.
This occurs in each of the soundings at the Flunde Islands (Sutherland), and is com-
mon and of middling size in most of them. It is found also at 150 fathoms in Baffin’s
Bay, lat. 76° 30', long. 77° 52' (Parry). It is small at Shetland (Brady).
Plate XVI. figs. 38-40 (North Atlantic).
Pulvinulina Karsteni,~Rexiss, sp. (Zeitsch. deutsch. geol. Ges. 1855, vol. vii. pi. 9. fig. 6),
is usually smaller and more conical than P. Menardii, also rounder, quite smooth, and
free from the limbation on its upper face, which is present in P. Menardii ; on its lower
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 397
face, however, the margin and sometimes the septal furrows are limbate (a feature
usually wanting in P. Menardii) ; an umbilical knob is sometimes present also ; and
with this as a nave, and the septa for spokes, the shell has a wheel-like aspect.
A closely allied and still more conical form (B. Schreibersii, D’Orb., For. Foss. Vien.,
pi. 8. tigs. 4-6), having a stellate umbilicus and neatly radiating septa, is the leading
member of the group of varieties of P. repanda , among which P. Karsteni is arranged ;
it is found recent in the muds of the Gulf of Suez and the Red Sea (at 40 fathoms and
thereabouts), and is fossil in the Tertiary beds of Tuscany and the Vienna Basin.
Though differing from it a little in details, the North Atlantic specimens here figured
are still more like Reuss’s figure than is the Arctic specimen, Plate XIV. fig. 15, which
in some respects is nearer to D’Orbigny’s figure of Pulvinulina Antillarurn (Foram. Cuba,
pi. 5. figs. 4-6), an allied form. Reuss*s figure is intermediate to the Arctic and North
Atlantic specimens.
In Trinity Bay P. Karsteni is rare but large at 133 fathoms, lat. 48°T8', long. 52° 56'.
It occurs at 2700 fathoms in the South Atlantic.
Pulvinulina repanda , Fichtel and Moll, sp., Var. elegans , D’Orbigny, sp. Plate XVI.
figs. 44-46 (North Atlantic).
Our specimens show an unusually non-limbate condition of Pulvinulina elegans , which
is a subtype of the P. repanda group, and was chosen as a species by D’Orbigny from
amongst Soldani’s figures (Sagg. Oritt. pi. 2. fig, 2, R ; Ann. Sc. Nat. vii. p. 276, No. 54).
P. elegans has a neat, smooth, and highly polished shell, varying always in limbation
and conicity. The excess of characters in this subtype is found in P. caracolla , Rcemer,
sp., P. ornata , Roem., sp., and P. D'Orbignii , Rcem., sp. (Norddeutsch. Kreid. pi. 15.
figs. 22, 24, 25), of the Cretaceous deposits. In our specimens we have nearly an equa-
lity with P. Partschiana , D’Orb., sp. (For. Fos. Vien. pi. 8. figs. 1-3), excepting as to
limbation : and, further, we may regard our specimens as feeble forms of P. elegans with
a tendency towards P. umbonata , Reuss (Zeitsch. d. g. Ges. vol. iii. pi. 5. fig. 35).
P. elegans abounds at from 100 to 200, and even to 300 fathoms. Forms inter-
mediate to P. elegans and P. Karsteni are common in clays of the Secondary Forma-
tions (Oxford and Kimmeridge Clays, and Upper Trias of Chellaston).
In the North Atlantic P. elegans is common, but small, at 78 fathoms on the eastern
plateau; rare and small at 1660 fathoms in the abyssal area (“Boreal”); but rather
common and larger at 1450 fathoms. It is sa 11 at 15 fathoms in the Irish Sea (Brady).
Genus Spirillina.
Spirillina vivipara , Ehrenberg. Plate XV. fig. 28 (Arctic).
For an account of Spirillina ;, see Ann. Nat. Hist. 2 ser. vol. xix. p. 284, and Carpen-
ter’s Introduct. Foram. p. 180. There is often a difficulty in distinguishing this form
from its isomorph, the vermiculate Pulvinulina ; the numerous and non -segmented
whorls decide the doubt in this instance.
3 H
MDCCCLXV.
398
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Sp. vivipara is rare anywhere, and always small. We have it in the mixed sands from
Norway (MacAndrew and Barrett), and from 60 to 70 fathoms, Hunde Islands (Dr.
Sutherland) ; in deep water it is represented by the better developed Sp. margaritifera,
Williamson.
Genus Patellina.
Patellina corrugata, Williamson. Plate XV. fig. 29 a, 29 b, 29 c (Arctic).
This species has been well figured and described by Professor Williamson (Monogr.
p. 46, pi. 3. figs. 86-89); see also Carpenter’s Introd. Foram. p. 230.
We have P. corrugata from the Hunde Islands (Dr. Sutherland’s dredgings), at from
30 to 70 fathoms; where it is common and small throughout. Professor Williamson
had it from the same source, and found it in several sands on the British coasts. It is
present in most sea-beds that are rich with Foraminifera, from the littoral zone down to
500 fathoms ; but is rarely in great abundance.
Genus Nummulina.
Nummulina perforata, Montfort, sp., Yar. planulata, Lamarck. Plate XIV. figs. 45 a,
45 b (Arctic).
From the Bed Sea Fichtel and Moll got two little Nummulina very similar to the
specimens before us; Professor Williamson also has similar specimens from the British
coast; and in Mr. Jukes’s Australian dredgings Nummulina of like character abound,
but larger, and passing into Operculina. These are degenerate forms of Nummulina
planulata , once so abundant in the Eocene (or Nummulitic) Tertiary period, and exist-
ing still later in, at least, the Vienna area (Middle Tertiaries). N. planulata itself is a
simple form of the better-developed N. perforata, Montfort, which in its extreme growth
became N. nummularia , Brug. (N. complanata, Lam.).
This small form of N. planulata (subvar. radiata, Fichtel & Moll.) is -rather common
at the Hunde Islands in 25 to 30 fathoms. See also Ann. Nat. Hist. ser. 3. vol. v.
pp. 105-107.
Besides the above-mentioned localities, the Abrolhos Bank in the South Atlantic and
Bombay Harbour are places where N. planulata has been found.
Nummulina perforata, Montfi, sp., Var. ( Operculina ) ammonoides, Gronovius, sp.
Plate XIV. figs. 44 a, 44 b (Arctic) ; Plate XVII. figs. 62, 63 (North Atlantic).
This is the diminutive and northern representative of the much larger Operculina
complanata, Defrance, sp., which is a varietal form of Nummulina. The last (Nummu-
lina) is but poorly represented now-a-days (as far as our knowledge goes) ; but Oper-
culina is sometimes almost, if not quite, as large in the Australian, New Zealand, and
Philippine seas as ever it was in the Cretaceous, Eocene, and Miocene times. See Ann.
Nat. Hist. 3 ser. vol. viii. p. 220, &c. Dr. Carpenter has specially studied the structure
of Operculina, Phil. Trans. 1859 ; and Introd. Foram. p. 247, &c. pi. 11.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 399
Operculina ammonoides is very common in the mixed sands from Norway (Mac Andrew
and Barrett). On the Irish plateau of the North Atlantic it is common at 43, 78, 90,
223, and 415 fathoms ; and rare at 200 fathoms. It abounds in the North British seas ;
in Professor Williamson’s Monogr. it appears under the name of Nonionina elegans. It
is found also in the Mediterranean and Red seas, and at Australia and Fiji.
Genus Polystomella.
Polystomella crispa, Linn., sp. Plate XIV. fig. 24 (Arctic) ; Plate XVII. fig. 61 a, 61 b
(North Atlantic).
Polystomella comprises many closely allied forms, which, on account of their appa-
rent dissimilarity, have been usually grouped under Nonionina and Polystomella. Their
differences, however, are not sufficient to destroy the value of their correspondences in
structure. The shells are symmetrically discoidal, either lenticular or subglobular,
more or less Nautiloid, having from about fifteen to thirty, or many more, neatly fitting,
more or less sickle-shaped chambers, with the aperture at the base of the septa; and
this may be either a simple low arch-like opening, or it may be crossed by bars so as to
be a grating, or a row of pores ; this multiplicity of stolon-passages is the condition
which gave the name to this genus in particular, and to the “Foraminifera” altogether*.
The gradations from the simply notched septum of some Nonionince , to the barred aper-
tures of others (N. Faba, Fichtel and Moll, sp.), and thence to the curved row of pores
in Polystomella proper, are very well marked in numerous modified varieties. Another
feature of the genus is the masking of the septal furrows of the shell, by “ retral pro-
cesses,” or lobes on the posterior edges of the chambers, connected by bridges of exoge-
nous shell-matter to the fronts of the preceding chambers, and thus forming pits or
“ fossettes” along the septal lines. The mouths of the canal-system open into the “ fos-
settes;” but the latter are not a part of that system. The processes and the bridges or
bands vary much in thickness, in proportion to the higher standing of the more strongly
grown varieties of this species ; and this increase of shell-matter on the surface of the
shell, until it has a sculptured or basket-work appearance, accompanied more or less with
keel, spines, and umbones, is also traceable through very gentle gradations.
The “ bridges ” occur freely, in P. Arctica and other forms, when the retral lobes are
nearly obsolete, and thus they form crenulations on the edges of the chambers.
As the soft parts of the animal afford us no distinctive specific characters, all these
modifications of shell-structure fall into a series of varietal differences among the indi-
viduals of one species, subject to different conditions of existence and consequent modes
of growth.
In its symmetry of shell Polystomella resembles Nummulina, but it has a canal-
system different from that of the latter ; and, though the aperture in Nummulina is in
the same position (at the base of the septum) as in Nonionine Polystomellce, yet the very
* As being distinct in so much from the single-tubed Cephalopods, with which they were classed.
3 h 2
400
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
slight attempt to modify it by subsidiary pores in Nummulina is sufficient to indicate an
inability to depart from a special plan. The feebler Polystomellce ( Nonionince ) are, with
their neat shell and simple aperture, isomorphic with some Nummulince, especially if we
compare some of the more strongly limbate of the former with the small “ Opercu-
line ” or “Assiline” varieties of the latter ( Nonionina limba compared with Operculina
ammonoides) ; but the shell-tissue is more dense and tubuliferous in the latter (as in
Nummulina proper), and the perfect marginal rim and the canal-system are wanting in
the former.
Again, both in some of its higher [Polystomella macella ) and lower forms ( Nonionina
turgida) Polystomella loses its horizontal symmetry, which Nummulina (except in some
Operculine individuals) never does ; the asymmetrical ally of Nummulina ( Amphiste -
gina) being sufficiently differentiated as to canal-system and other points to be regarded
as specifically distinct.
The close linking of Nonionince with Polystomella , especially by means of the gra-
duated subdivision of aperture, and modification of lateral fossettes, retral processes,
and septal bridges, is too strong to be in any way antagonized by the merely isomor-
phic resemblances of the former with Nummulina ; and “Nonionina” is rightly sup-
pressed as a generic term, being merged in “ Polystomella,” which well represents the
peculiar features of the fairly developed, but not exaggerated, natural type. See Ann.
Nat. Hist. 3rd ser. vol. v. p. 103, &c. ; Carpenter’s 4 Introduct.’ p. 286, &c.
Scheme of the Polystomella.
A. Canal-system, retral processes of the chambers, and the septal bridges and apertural bars, all highly developed.
Polystomella eraticulata, Fichtel and Moll, sp.
B. Canal- system feebly developed ; hut the retral processes, septal bridges, and apertural bars perfect.
P. ceispa, Linn., sp. P. strigillata, Fichtel and Moll, sp.
P. unguiculata, Gmel., sp. P. macella, Fichtel and Moll, sp., &c.
C. Canal-system, the septal bridges, and apertural bars -well-developed, but the retral processes abortive.
P. Arctica, Parker and Jones.
D. Canal-system and retral processes feebly developed, but the bridges over the septal lines and the bars across
the aperture perfect.
P. striatopunctata, Fichtel and Moll, sp., and P. Faba, Fichtel and Moll, sp.
E. Canal-system, retral processes, septal bridges, and apertural bars all abortive more or less.
Nonionina limba, D’Orb. N. stelligera, D’Orb.
N. asterizans, Fichtel and Moll, sp. N. Scapha, Fichtel and Moll, sp.
N. depressula, Walker and Jacob, sp.
F. Canal-system, retral processes, septal bridges, and apertural bars all obsolete: there may, however, be gra-
nular shell-growth on the umbilici.
N. granosa, D’Orb. N. umbilicatula, Montagu, sp. N. turgida, Williamson, sp.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 401
Both the feeble (Nonionine) and the well-grown varieties of Polystomella are distri-
buted very widely, but avoid great depths. The thick-shelled P. craticulata is found in
tropical seas ; the medium-conditioned P. crispa is extensively spread about in temperate
seas ; P. Arctica and P. striatopunctata are the best of the species found in cold seas.
The Nonionince accompany their better-grown congeners ; N. asterizans and N. depres-
sula affecting temperate climates ; N. Scaplia and N. umbilicatula being found more often
in the warmer seas.
Polystomella crispa stands midway between those Nonionince that begin to take on a
barred aperture and perforated septal furrows, and those that have cribriform septa and
a surface masked with septal bridges and other exogenous shell-matter ; it is therefore
a good type, showing the generic and specific characters without exaggeration. It has
been well illustrated and described by Williamson, Carpenter, and Schultze; and its
many modifications, in the recent and fossil state, have received as many names. In
some Tertiary beds P. crispa is plentiful ; and it abounds at the present day in temperate
and warm seas.
We find P. crispa in the dredgings from the Hunde Islands (at 25 to 30 fathoms) rare
and small; and very rare and small in the North Atlantic at 725 fathoms, north of the
Newfoundland Bank.
Polystomella crispa , Linn., sp., Var. Arctica , nov. Plate XIV. figs. 25-30 (Arctic).
One of the varietal stages presented by the simpler Polystomellce is characterized by
double pores for the canals in lines along the septal furrows of the shell, an advance
upon the simple single pores of P. striatopunctata , and an approach to the higher
Polystomellce. These double-pored furrows belong to a rounded, bun-like, Nonionine
shell, with barred aperture, sparsely perforated septa, and a tendency to irregularity of
growth ; the neat, definite, lenticular, sharp-edged, discoidal shell of Polystomella proper
being but poorly represented as yet. The essential characters, however, of pores in the
furrows and septal apertures are not to be mistaken, although the retral processes of the
chambers and the intervening fossettes are very rudimentary. The spiral lamina is
finely perforate.
This form differing from the smaller P. striatopunctata , Fichtel and Moll, sp., in
having double pores for its lateral canals, shows thus much a differentiation of the shell-
structure in relation to the forking tubes, which are single in P. striatopunctata (figs.
31-34). With this exception, and with some additional apertures, P. Arctica keeps to
the simple type ; but it attains a semigigantic size, having a similar relation to P. stria-
topunctata that P. craticulata has to P. crispa.
One individual (fig. 27) shows a tendency to produce rough exogenous accumulations
of shell-substance, as is the habit of P. craticulata.
P. Arctica is peculiar to the most northern seas, and occurs plentifully at the Hunde
Islands at from 30 to 40 and 60 to 70 fathoms (Sutherland) in company with P. striato-
punctata. Mr. H. B. Brady has found it in Mr. Jeffreys’s dredgings made at Shetland,
in some abundance, and of a brown colour.
402
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Polystomella crispa, Linn., sp., Var. striatopunctata, Fichtel and Moll, sp. Plate XIV.
figs. 31-34 (Arctic) ; Plate XVII. fig. 60 a , 60 b (North Atlantic).
This is a smooth, round-edged, Nonionine shell, variable in its thickness and in the
number of bridges over the septal furrows. The aperture is more or less divided by bars,
and may have supplemental pores.
Individuals presenting two stages in this variety are described and figured by William-
son under the name of Polystomella umbilicatula and P. umbilicatula , var. incerta,
Monograph, p. 42, &c., pi. 3. figs. 81, 82, 82 a. Some of our figures (Plate XIV. figs.
32-34) show but little of the septal markings ; but in fig. 31, and Plate XVII. fig. 60,
these are much more apparent, for the furrows are more distinctly bridged over by the
posterior crenulation and retral processes of the chambers, and conspicuous fossettes are
formed. Schultze has also illustrated this form (Ehrenberg’s Geoponus Stella-borealis ,
well figured by him in the Berlin Acad. Trans. 1841) and some near allies in his 4 Org.
Polyth.’ pi. 6. figs. 1-9 [Polystomella gibba, P. Stella-borealis , and P. venusta).
P. striatopunctata is widely distributed in both warm and cold seas, but not in deep
water. It occurs in Tertiary and Post-tertiary deposits, sometimes abundantly, and is a
characteristic fossil of the Post-pliocene clays of Canada (Dawson) and of the coast of
Scotland (Quart. Journ. Geol. Soc. vol. xiv. p. 521, note).
We have P. striatopunctata , rather rare and small in the mixed Norwegian sands
(MacAndrew and Barrett’s dredgings) ; in all Dr. Sutherland’s dredgings from the
Hunde Islands (25-70 fathoms), where it is usually common and large. Also from
Baffin’s Bay (Parry), lat. 75° 10', long. 60° 12', rare and very small; lat. 76° 30', long.
77° 52', 150 fathoms, common and middle-sized; lat. 75°, long. 59° 40', 220 fathoms,
very rare and very small. In the North Atlantic it is found on the eastern marginal
plateau at 43 fathoms common and small ; at 78 fathoms very rare and very small ; at
223 fathoms rare and small; and north of the Newfoundland Bank it occurs rare and
small at 145 fathoms, very rare and very small at 161, rather common and middle-sized
at 740 ; rather rare and small at 725; rare and small at 954 fathoms.
Polystomella crispa , Linn., sp., Var. (Nonionina) Fab a, Fichtel and Moll, sp. Plate XIV.
fig. 36 (Arctic).
Nonionina Faba is a small, delicate, ovate-oblong shell, with the later chambers
much larger than those first formed. The septal furrows are bridged by little processes
from the advancing chambers, and the septal aperture is barred or subdivided. In these
latter features N. Faba shows an advance of structure beyond N. Scapha towards Poly-
stomella proper, in which the septa are cribriform and the surface of the shell fene-
strated.
It occurs both fossil and recent in the Mediterranean area. We have it from
the Hunde Islands, where it is rather rare and of middle size at from 25 to 30 fathoms ;
rather common and large at 30 to 40; and common and large at 60 to 70 fathoms
(Sutherland’s dredgings).
N. Faba among these delicate oblong Nonionina, and P. striatopunctata among the
F0RAMIN1FERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 403
less feeble Nautiloid forms make advances towards the true Polystomellan characteristics ;
thus showing that they certainly are within one and the same specific limits ; moreover,
the next variety, N. Scapha, is seldom quite free from bridges across the divisions of its
chambers on each spiral lamina, as may be seen in figs. 37 and 38, Plate XIV.
Polystomella crisp a, Linn., sp., Var. ( Nonionina ) asterizans , Fichtel and Moll, sp. Plate
XIV. fig. 35 (Arctic) ; Plate XVII. figs. 54 a, 54 b (North Atlantic).
This is a small, many-chambered, Nautiloid Nonionina , somewhat variable in its
features, but having a slight umbilical growth of exogenous shell-matter often radiating
along the septal furrows for some distance. This star-like limbation is much exaggerated
in N. Limba , D’Orb. (Modeles, No. II), and curiously modified with flaps in N. stelligera,
D’Orb. (For. Canar. pi. 3. figs. 1, 2). N. asterizans varies as to its granulations and
stellate umbo, readily passing into N. granosa and into N. stelligera. Fig. 35 is of a
stronger make than the latter, and is such as frequents deeper water than that does. It
is from the Hunde Islands (Sutherland’s dredgings) at from 25 to 30 fathoms, where
it is common but small. N. asterizans is common in the British seas in shallow water.
Plate XVII. fig. 54 differs from the Arctic specimen as to the umbo, but is not sepa-
rable. It is from 740 fathoms north of Newfoundland Bank.
The tribe of small Nonionince converging round Nonionina asterizans , although con-
veniently considered as a subspecific group, yet in reality are essentially of the same
specific type as that to which Polystomella crispa belongs. They may be said to present
arrested or feebly developed conditions of the form in which, under other circumstances,
a luxuriant growth of exogenous shell-matter symmetrically bridges over the septal lines,
and otherwise thickens and ornaments the shell. Nonionina Limba , D’Orb., belongs to
this group, and is very apt to take on the characters of the type in connexion with its
own, and thus to pass insensibly into it. It is a Tertiary form, at Grignon, Bordeaux, &c.
Polystomella crispa , Linn., sp., Var. ( Nonionina ) depressula, Walker and Jacob, sp. Plate
XIV. figs. 39 a , 39 b (Arctic).
This is a delicate feeble form of Nonionina asterizans , Fichtel and Moll, sp., with the
stellation of the umbilici imperfect.
It is common in the shallow sea-zone and in. the brackish water of river-mouths and
salt-marshes of the British area ; and is the commonest shell in the clay of our Eastern
Counties fen-district, excepting at the margin of that sub-recent deposit, for there Tro-
chammina inflata attains its highest development and abounds most. This form is very
apt to turn up, all the world over, in such shallow water as is rendered somewhat unfit
for rhizopodal life by the presence of large quantities of earthy or vegetable matter,- —
for instance, in bays, harbours, estuaries, &c.
We have it from the Hunde Islands (Sutherland’s dredgings) common and small at
from 25 to 30 and 50 to 70 fathoms ; common and middle-sized at from 60 to 70 fathoms.
404
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Polystomella crispa, Linn., sp., Var. (Nonionina) stelligera , D'Orb., sp. Plate XIV. figs.
40, 41 (Arctic).
This delicate and variable Nonionina was first described by D’Okbigny as occurring at
the Canaries (For. Canar., p. 123*, pi. 3. figs. 1, 2). It differs from N. asterizans in
being altogether more delicate and feeble, and in the exogenous matter having the form
of a radiating series of thin flaps, which cover over the inner half of the septal sulci on
each face of the shell.
It inhabits shallow waters of the Atlantic and the Australian coast. We find it in
the dredgings from the Hunde Islands, throughout, from 25 to 70 fathoms, and in the
mixed sands from Norway.
Polystomella crispa, Linn., sp., Var. ( Nonionina ) Scapha, Fichtel and Moll., sp. Plate
XIV. figs. 37-38 (Arctic); Plate XVII. figs. 55, 56 (North Atlantic).
In this, almost the lowest form of Nonionina (the small and more or less oblique
N. turgida being still feebler), the successive chambers enlarge at a greater ratio than
they do in N asterizans and its allies ; hence the shell is ovato-oblong instead of discoidal ;
it has the shape of the Argonauta, instead of that of the Nautilus. It is N communis ,
D’Orb. The shell varies from the complanate condition (fig. 37) to the gibbose (fig. 38),
and to the subglobose (figs. 55, 56) ; occasionally faint traces of the septal fossettes
characteristic of Polystomella can be recognized (fig. 38 a) ; but the aperture is still a
simple arch-like slit (fig. 38 b) ; whilst in the next stage (N. Faba , fig. 36) the fossettes
and the barred aperture occur together.
N. Scapha occurs in warm seas rarely at great depths ; it is found in the British seas ;
and the Arctic dredgings show that it also lives at high latitudes. It occurs in Baffin’s
Bay at lat. 75° 10', long. 60° 12', rare and of middling size; lat. 76° 30', long. 77° 52',
at 150 fathoms, very common and of middling size. At the Hunde Islands it is
abundant at from 25 to 70 fathoms, sometimes of large size, usually middling.
It abounds in many Tertiary deposits, Grignon, Bordeaux, Subappennines, San
Domingo, English Crag, &c.
Plate XVII. figs. 55, 56 (North Atlantic).
Nonionina Scapha is rare and small at 225 fathoms on the Irish plateau of the North
Atlantic; absent apparently in the central area; rare and of middle-size at 145 fathoms
north of the Bank; very rare and middling at 161, 329, and 725 fathoms, and very
rare and very small at 954 fathoms along the same tract ; in Trinity Bay it is rare and
middle-size at 124, 133, and 150 fathoms.
The very gibbose specimen, figs. 55, 56, is the same as N Labradorica , Dawson
(Canad. Geol. Nat. vol. v. 1860, p. 192, fig. 4), found by him both recent in the Gulf
of St. Lawrence and fossil in the Post-pliocene clays of Labrador and Maine.
* In the text the name given is “ stelligera,” in the Plate it is “ stellifera ” ; of course the former should be
received.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 405
The specimens from Newfoundland Bank are rare and have a deadish look, as if
drifted from their more favourable northern habitats.
Polystomella crispa, Linn., sp., Var. ( Nonionina ) umbilicatula , Montagu, sp. Plate XIV.
figs. 42 a, 42 b (Arctic); Plate XVII. figs. 58, 59 (North Atlantic).
This is a small, neat, many-chambered, Nautiloid Nonionina , with hollow umbilici.
See Ann. Nat. Hist. 3rd ser. vol. iv. pp. 346 & 347, and vol. v. p. 101, &c., for a com-
parison of this and other Nonionince. It is common at greater depths than most other
Nonionince, except N. Scapha , affect ; it is found in warm seas, and occurs in many
Tertiary deposits.
We have it in the mixed sands from the Norway coast (MacAndrew and Barrett).
In the North Atlantic N. umbilicatula is common and of middle-size on the marginal
plateau off Ireland, at 78, 90, 223, and 415 fathoms; in the abyssal depths it is rare and
small at 1776, rather common and middle-sized at 1950, rather common and small at
2050 and 2176 fathoms; and at 2350 fathoms in the “ Boreal” part of the abyss it is
rare and small : north of Newfoundland Bank, at 329 fathoms, and in Trinity Bay at
150 fathoms, it is very rare and small; cold water having as bad an influence on it as
abyssal depth.
This form, being flush-celled, is more thoroughly changed in character from the type
than the feeble varieties found in shallow water, such as P. stelligera and P. depressula.
In these the vesicularity of the chambers allows of the formation of some rudiments of
the retral processes, the overlying bridges, and the intervening fossettes ; but in this
deeper-sea variety the septal walls of contiguous chambers become perfectly adapted,
and their edges grow close together at the surface of the shell. This is well shown in
the recent and fossil specimens of this kind from the Mediterranean area ; further north,
however, it scarcely holds its own, and intermediate forms are always turning up, which
connect this with the vesicular varieties.
Polystomella crispa, Linn., sp., Var. ( Nonionina ) turgida, Williamson, sp. Plate XVII.
figs. 57 a , 57 b , 57 c (North Alantic).
A delicate ovate Nonionina ; the chambers increasing so rapidly in size that the dis-
coidal form is lost, and we have the shape of the Argonauta instead of the Nautilus.
The latter chambers, too, in adult specimens are apt to be swollen at the umbilical
margin, concealing the spiral parts of the shell, and hanging over a little more on one
side than the other.
Our figured specimen is much thicker and more symmetrical than Professor William-
son’s Botalina turgida (Monogr. p. 50, pi. 4. figs. 95-97), but they both belong to the
same variety.
N. turgida is found in shallow and brackish water in the British area ; and occurs
especially in the sub-recent clay of Peterborough Fen, rather common, but extremely
small, starved, and one-sided.
mdccclxv. 3 i
406
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
We have it from the Irish plateau of the North Atlantic at 43 and 223 fathoms, rare
and small.
Genus Valvulina.
Valvulina triangularis, D’Orbigny, Yar. conica , nov. Plate XY. fig. 27 (Arctic).
This is a very simple condition of Valvulina. The triserial arrangement of chambers
forms a smooth conical figure, without any trace of the three flat faces so usual in this
species. A similar condition, but depressed, is shown in V. fusca, Williamson, sp.
Valvulina cornea , Parker and Jones, was described and figured in the Annals Nat.
Hist. 2 ser. xix. p. 295, pi. 11. figs. 15, 16, but not named separately from the better
developed type, which has a triangular apex. It is also figured by Dr. Carpenter, op.
cit. pi. 11. fig. 16. It occurs with the typical form, both in the fossil and the recent
state (extremely large in sea-sands from Melbourne) ; it is rare and small in the mixed
sands from Norway (MacAndrew and Barrett). It lives also in the Mediterranean and
on the Abrolhos Bank, South Atlantic.
The type, V. triangularis , D’Orb. (Modeles, No. 23 ; Carpenter’s ‘ Introd. Foram.’
p. 146, pi. 11. fig. 15), though occurring of large size (with V. conica, also very large)
in Australia, is usually rare ; but it has been marvellously common and large in Tertiary
times, as shown by specimens from Grignon and Hautville (France).
Lituola nautiloidea, Lamarck, Var. Canariensis, D’Orbigny, sp. Plate XY. figs. 45 a,
45 b (Arctic) ; Plate XVII. figs. 92-95 (North Atlantic).
Of the disco-spiral Lituolce most are attached and therefore more or less plano-convex ;
when growing free, however, they attain the more symmetrical, somewhat biconvex, and
nautiloid shape of L. Canariensis , without attaining the outgrowing rectilinear series
of chambers shown in Lamarck’s L. nautiloidea, and still more in L. irregularis,
Rcemer, sp.
Lituola Canariensis , D’Orb., sp. (Foram. Canaries, p. 128, pi. 2. figs. 33, 34), has, like
other Lituolce, a rusty coloured shell-substance among the sand-grains that largely make
up its shell. We have a few large specimens from Finmark (East of Rolfs Oe),
30 fathoms (MacAndrew and Barrett) ; and some small specimens from the mixed
sands from Norway. At the Hunde Islands (Dr. Sutherland) it is large and common
throughout ; and in the sands from Baffin’s Bay (Parry) it is most common and some-
times large.
In the North Atlantic it is rare ; on the Irish plateau it is small at 43 fathoms and
middle-sized at 223 fathoms ; and it is middle-sized at 1203 fathoms north of the Bank,
and at 133 fathoms in Trinity Bay. The British coasts, Abrolhos Bank, Hobson’s Bay
(Australia), and Fiji are other localities for L. Canariensis.
Fig. 94 is probably not worth separating from L. Canariensis ; its chambers are either
imperfect or obsolete.
EORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 407
Lituola nautiloidea, Lamarck, Var. globigeriniformis, nov. Plate XV. figs. 46, 47
(Arctic) ; Plate XVII. figs. 96-98 (North Atlantic).
In this low form of Lituola the chambers are subglobular and agglomerated, pre-
senting an isomorph of Grlobigerina ; the somewhat scanty and rusty-red shell-substance
cementing the sand-grains is characteristic, as in Lituola nautiloidea proper.
Lituola globigeriniformis is small and common at the Hunde Islands (Dr. Suther-
land) from 30 to 70 fathoms. It is small also in Baffin’s Bay; being common at
75° 10' lat., 60° 12' long., and rare at 75° 25' lat., 60° long. (314 fathoms), and 75° lat.,
59° 40' long. (220 fathoms).
In the North Atlantic it is rare and middle-sized at 1660 fathoms in the “ Boreal ”
portion of the abyss ; and very rare and small north of the Bank at 145 and 954
fathoms. It is figured by Dr. Wallich in ‘The North-Atlantic Sea-bed,’ pi. 6. fig. 22.
L. globigeriniformis , Parker and Jones, is common, but small, in the Mediterranean;
in our paper in the Quart. Journ. Geol. Soc. vol. xvi. Table, p. 302, it is referred to as
“ L. pelagica , D’Orb., sp.,” as we then mistook the yellowish acerose Globigerina named
“ Nonionina pelagica ” by D’Orbigny for our Lituola. It is present in the Bed Sea, the
Indian Ocean, and the South Atlantic.
Lituola nautiloidea , Lamarck, Var. Scorpiurus , Montfort, sp. Plate XV. figs. 48 a,
48 b (Arctic).
Lituola Scorpiurus, Montfort, sp., is a simple, linear, slightly curved, and, as it were,
abortive variety of L. nautiloidea , Lamarck (see Ann. Nat. Hist. 3 ser. vol. v. p. 297 ;
and Carpenter’s ‘ Introd. Foram.’ p. 143). It is of very common occurrence in shelly
deposits, recent and fossil.
It is common and large at the Hunde Islands, 25 to 40 fathoms ; common and middle-
sized in Baffin’s Bay, 75° 10' lat., 60° 12' long. ; and rather common and very large at
150 fathoms, 76° 30' lat., 77° 52' long.
The late Mr. L. Barrett obtained large specimens of L. Scorpiurus in deep water off
Jamaica, of very large size, labyrinthic, and passing into L. Soldanii , Parker and Jones.
L. Scorpiurus lives also in the Adriatic, the North and South Atlantic, and in the Austra-
lian seas.
Genus Trochammina.
Trochammina squamata , Parker and Jones. Plate XV. figs. 30, 31a, 315, 31c (Arctic).
This is the subvesicular Rotaliform Trochammina (Quart. Journ. Geol. Soc. vol. xvi.
p. 305), having lunate, flattened chambers, several in a whorl, and regularly increasing
with the progress of growth ; it much resembles those flatter varieties of JDiscorbina
Turbo which are intermediate between L, globularis and 1). rosacea , but it has an
arenaceous shell ; it is also like some little scale-like varieties of Valvulina triangu-
laris ; but the latter have only three chambers in a whorl, and are more coarsely
sandy.
3 I 2
408
ME. W. K. PAEKEE AND PEOFESSOE T. E, JONES ON SOME
Trochammina squamata, the type of the species, is usually rare ; it is small and rare
at 360 fathoms off Crete (Captain Spratt’s soundings).
At the Hunde Islands (Dr. Sutherland’s dredgings) Troch. squamata is rare at 30 to
40 fathoms, common at 60 to 70 fathoms, but small throughout.
Trochammina squamata , Var. gordialis, Parker and Jones. Plate XV. tig. 32 (Arctic).
Trochammina gordialis , Parker and Jones (Carpenter’s ‘Introd. Foram.’ p. 141, pi. 11.
tig. 4), presents sometimes an irregularly coiled tube, having but little segmentation ;
sometimes it presents long, in wound, tubular chambers.
It is common and small at 60 to 70 fathoms at the Hunde Islands, together with the
type. It occurs in the Red Sea, and is found involutely coiled (commencing with a few
irregularly segmented chambers, and continued as a long tube, turned and twisted on
itself) in the Indian seas ; the so-called Serpula pusilla of the Permian limestones is
a very similar little Foraminifer.
Troch. incerta , D’Orb., sp., is discoidal, tubular, and without segments. The next stage
beyond that seen in fig. 32 is that form of Troch. squamata shown by fig. 31.
Genus Cornuspira.
Cornuspira foliacea, Philippi, sp. Plate XV. fig. 33 (Arctic).
The characters and relationships of this flat, spiral, non-segmented Milioline Forami-
nifer are treated of in Carpenter’s ‘ Introd. Foram.’ p. 68. It inhabits the shallow sea-
zones of every climate, and is found fossil (Tertiary).
We find it common in Dr. Sutherland’s dredgings from the Hunde Islands, where it
is small at 60 to 70 fathoms, and of middle size at 25 to 30 fathoms. It is figured by
Dr. Wallich in ‘ The North-Atlantic Sea-bed,’ pi. 5. fig. 12.
C. foliacea is extremely large (fossil) in the Crag of Sutton, Suffolk ; in the recent
state it is very large off Crete, and is found also living on the British coasts, in the Red
Sea, the South Atlantic, and on the western and southern shores of Australia.
Genus Miliola.*
Miliola ( Spiroloculina ) planulata, Lamarck. Plate XVII. fig. 82 (North Atlantic).
The type of the symmetrical and flattened group of Miliolce, Spiroloculina planulata,
Lamarck, is often abundant in sea-sands and in Tertiary deposits.
In the North Atlantic it is rare ; of middle size at 43 fathoms off Ireland ; middle-
sized at 2050 fathoms, and small at 2330 fathoms in the abyssal area. Dr. Wallich
figures it in ‘The North-Atlantic Sea-bed,’ pi. 5. fig. 13.
For remarks on this genus (type, M. Seminulum), see Carpenter’s Introd. Foram. pp. 74, &c.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 409
Miliola ( Spiroloculina ) limbata, D’Orbigny. Plate XVII. figs. 83 a, 83 b (North Atlantic).
Here the edges of the chambers are limbate, or thickened with shell-growth, a non-
essential feature. It is figured by Soldani and named by D’Orbigny, Ann. Sci. Nat.
vol. vii. p. 299, No. 12.
We have Spiroloculina limbata rare and small from the Irish marginal plateau of the
North Atlantic, at 78 fathoms. It is not rare in the existing seas, and occurs in the
Tertiary deposits.
Miliola ( Biloculina ) ringens, Lamarck. Plate XV. figs. 42-44 (Arctic).
Taking the Biloculine Miliolce by themselves, this well-known common Biloculina
ringens , Lamarck, is the type of a very variable group. Not only the degree of globo-
sity of the chambers, but the amount of overlap at the sides or at the ends, constitute
infinite variations, presented in all seas.
Large Biloculina, but subject to great differences in the points above alluded to, were
found abundantly in nearly all the dredgings from Norway. Fig. 44 represents a highly
globose and striated specimen from Norway. Dr. Wallich figures B. ringens in ‘ The
North- Atlantic Sea-bed,’ pi. 5. figs. 1, 3, 4, 6.
Miliola ( Biloculina ) depressa, D’Orbigny. Plate XVII. figs. 89 a, 89 5 (North Atlantic).
This depressed form of Biloculina ringens is not uncommon in both the recent and
fossil (Tertiary) states. D’Orbigny illustrated it by his Modele, No. 91.
It occurs in several soundings from the North Atlantic, though rare in each. It is
small on the Irish plateau at 43 and 78 fathoms; small at 2176 fathoms, and middle-
sized at 1450, 1660, and 2350 fathoms in the abyss. It is figured in Dr. Wallich’s
‘ North- Atlantic Sea-bed,’ pi. 5. figs. 2, 5, 8.
Miliola ( Biloculina ) elongata, D’Orbigny. Plate XVII. figs. 88, 90, 91 (North Atlantic).
Biloculina ringens contracted gives B. elongata , figured by Soldani and named by
D’Orbigny, Ann. Sci. Nat. vol. vii. p. 298, No. 4, and not rare wherever other Bilocu-
lince exist.
We have B. elongata from the North Atlantic, small and rare in the deep, at 1950,
2050, and 2330 fathoms.
Miliola ( Triloculina ) tricarinata, D’Orbigny. Plate XV. fig. 40 (Arctic).
Triloculina tricarinata , D’Orb. (Modeles, No. 94) differs from Tr. trigonula, Lamarck,
in having produced or keeled edges. Our figured specimen has rather flatter sides than
are usual.
Tr. tricarinata , D’Orb., has a very wide distribution and, like T. trigonula , Lam.,
abounds in some Tertiary beds. The sea-sand near Melbourne, Australia, yields large
specimens of Tr. tricarinata , together with striped Tr. trigonula. At the Hunde
Islands Tr. tricarinata is small, common at 25 to 30 fathoms, rare at 60 to 70 fathoms.
410
MR. W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
Miliola ( Triloculina ) cryptella , D’Orbigny. Plate XV. fig. 39 (Arctic).
This is an extremely inflated and short Triloculine Miliola , its chambers overlapping
so much more than in the symmetrical trigonal forms, that in some instances the ante-
penultimate chamber is but little exposed. It is not common.
Triloculina cryptella, D’Orb., For. Amer. Mer. p. 70, pi. 9. figs. 4, 5, approaches
closely, in appearance, to Biloculina sphcera, D’Orb., op. cit. p. 66, pi. 8. figs. 13-16, with
which it was found at the Falkland Islands. B. sphcera has its chambers so much over-
lapping that it scarcely shows the penultimate chamber (as characteristic of Biloculina ),
Tr. cryptella having so much overlap in its chambers that it scarcely shows the ante-
penultimate (as characteristic in Triloculina').
Tr. cryptella is a curious isomorph of Sphceroidina (p. 369), and might easily be mis-
taken for it, for both are white in colour ; the texture, however, is hyaline in Sphceroidina
(related to Globigerina ), and opake in Triloculina , as in all Miliolce.
We have Triloculina cryptella from Baffin’s Bay, 75° 25' lat., 60° long., where it is
rather common and middle-sized at 314 fathoms.
Miliola ( Quinqueloculina ) Seminulum , Linne, sp. Plate XV. figs. 35 a, 35 b (Arctic) ;
Plate XVII. fig. 87 (North Atlantic).
Figs. 35 a, b represent a neat form of the typical and widely distributed Miliola (M.
Seminulum , Linn., sp.), such as is common in deepish water, and well figured by D’Orbigny
as Quinqueloculina triangularis (For. Foss. Vienn. p. 258, pi. 18. figs. 7-9). It is from
Norway.
Fig. 87, from the North Atlantic, is a sandy specimen, but is not so coarsely built up
as the variety known as Q. agglutinans , D’Orb. (Plate XV. fig. 37).
Q. Seminulum is common and large on the Norway coast; common and rather small
at the Hunde Islands ; rare and small at 220 fathoms in Baffin’s Bay.
In the North Atlantic soundings it is small; common at 43 and 78 fathoms, and rare
at 90 fathoms on the Irish plateau ; rare at 2035, 2050, and 2350 fathoms in mid-ocean ;
and rare and of middle size at 954 fathoms north of the Bank.
In his ‘North- Atlantic Sea-bed’ Dr. Wallich figures Q.Seminulum, pi. 5. figs. 9, 10, 15 ;
and Q. secans , fig. 7.
Q. triangularis takes the place of the typical Q. Seminulum in many parts of the Medi-
terranean and Red Seas, and of the Indian, South Atlantic, and Pacific Oceans.
Miliola ( Quinqueloculina ) agglutinans , D’Orbigny. Plate XV. figs. 37 a, 37 b (Arctic).
Quinqueloculina agglutinans, D'Orb. (For. Cuba, p. 195, pi. 12. figs. 11-13), is a well-
developed, often rusty-red, arenaceous Miliola Seminulum , of wide distribution, and
varying much with the character of the sea-bed. The shell-substance cementing the
grains of sand may be reddish in Quinqueloculina, though on white sand in Australia its
shell becomes white, and on black sand at Orotava, Canaries, it is black.
We have Q. agglutinans, of middle size, from the Hunde Islands (Dr. Sutherland),
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 411
rare at 30 to 40 fathoms, common at 60 to 70 fathoms. Is rare and middle-sized in
Baffin’s Bay, 75° .10' lat., 60° 12' long. (Parry).
Miliola ( Quinqueloculina ) Ferussacii, D’Orbigny. Plate XV. figs. 36 a, 36 b, 36 c
(Arctic);
Quinqueloculina Ferussacii, D’Orb. (Modeles, No. 32), is a coarsely ribbed or plicated
form of Q. Seminulum (the type of the Miliolce) ; it is very variable, and is known by a
host of names.
It is found in some abundance in the European and other seas, and also in the Ter-
tiary deposits.
At the Hunde Islands it is common and middle-sized at from 30 to 70 fathoms.
Miliola ( Quinqueloculina ) oblonga, Montagu, sp. Plate XV. figs. 34, 41 (Arctic);
Plate XVII. figs. 85 a, 85 b , 86 a, 86 b (North Atlantic).
When Miliola Seminulum , Linn., sp., is contracted in its growth, it produces very
variable forms, in which the normal lateral exposure of the chambers does not take
place ; and somewhat elongate, oblong, Quinqueloculine and Triloculine forms are the
result, such as Q. oblonga , Montagu, sp., which is often Triloculine in aspect, and has
been registered as Triloculina oblonga by D’Orbigny and others (see Annals Nat. Hist.
2 ser. vol. xix. p. 300); but it often has indications of its being really a poorly developed
Quinqueloculine Miliola. Quinque- and Tri-loculince are excessively variable shells,
both as to shape and ornament, and are amongst the most common Foraminifers in all
latitudes and depths. We have two genuine Triloculince in the Arctic dredgings (Hunde
Islands); but the so-called Triloculina oblonga is an ill-grown Quinqueloculina. It
usually abounds in company with the typical Miliola Seminulum ; the largest specimens
we know of are fossil in the Lower Crag of Sutton, Suffolk. It is one of the most
abundant of the Quinqueloculine varieties.
This feeble Quinqueloculina Seminulum, with a Triloculine aspect, is common and large
in most of the Norway dredgings (MacAndrew and Barrett) ; common and small at the
Hunde Islands (Sutherland) at 25 to 30 fathoms.
We have it very rare and very small from 2330 fathoms in the North Atlantic. Figs.
14 & 16, in pi. 5 of Dr. Wallich’s ‘ North-Atlantic Sea-bed,’ also illustrate this variety.
Miliola ( Quinqueloculina ) subrotunda, Montagu, sp. Plate XV. figs. 38 a, 38 b (Arctic).
A small, roundish, biconvex variety of Miliola Seminulum, Linn., often accompanying
other Miliolce. It may be said to be a dwarf of the variety Q secans, D’Orb., and is very
widely distributed.
At the Hunde Islands (Dr. Sutherland’s dredgings) it is common at 60 to 70 fathoms.
Miliola ( Quinqueloculina ) tenuis, Czjzek. Plate XVII. fig. 84 (North Atlantic).
A nearly complanate, but often curved, thin, more or less unsymmetrical Quinquelo-
412
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
culine Miliola , named Quinqueloculina tenuis by Czjzek in his description of some fossil
Foraminifera from the Vienna Basin, in Haidinger’s Abhandl. Wiss. vol. ii. p. 149,
pi. 13. figs. 31-34.
This tiny shell, which presents an extreme enfeeblement of Q. Seminulum, Spirolocu-
line in aspect and twisted on itself, occurs at great depths in the Mediterranean and
other seas. We find it fossil in the Lias clay of Stockton, Warwickshire.
In the North Atlantic Q. tenuis is small ; rather common at 415 fathoms on the mar-
ginal plateau off Ireland ; rare at 2050 fathoms in the abyss.
Description of the Plates.
PLATE XII.
Map of the Deep-sea Soundings, in the North Atlantic, from Ireland to Newfound-
land, by Lieut. -Commander J. Dayman, R.N., assisted by Mr. J. Scott, Master R.N.,
H.M.S. Cyclops, 1857. With a Section of the Bed of the Atlantic Ocean from Valentia
to Trinity Bay. The soundings are given in fathoms. Vertical scale 2000 fathoms to
1 inch. Scales as 15 to 1. See Appendix VII.
This Map is copied from Commander Dayman’s Report on the Soundings (1858);
indications of the Natural-History Provinces, and of the thirty-nine Soundings described
in this memoir, being added.
Note. — In the ‘ Nautical Magazine,’ vol. xxxi. No. 11, November 1862, was published
“ The Report on the Deep-sea Soundings to the Westward of Ireland, made in H.M.S.
Porcupine, in June, July, and August 1862,” by R. Hoskyn, Esq., R.N., with a Chart,
showing the slope of the Eastern Plateau to be, in that line of soundings, at a less angle
off Southern Ireland than Commander Dayman found it where he sounded.
Plates XIII.-XIX. illustrating the Foraminifera from the Arctic and North Atlantic
Oceans, and other Foraminifera from other parts of the Atlantic, the Pacific, and else-
where.
PLATE XIII. (ARCTIC FORAMINIFERA.)
[Figs. 1-19 are magnified 12 diameters ; figs. 20-58, 24 diameters.]
Fig. 1. Glandulina laevigata, D'Orbigny.
Fig. 2, a , b.
Fig. 3.
Fig. 4, a, b. Nodosaria Radicula, Linn. Various individuals passing from Glandulina
Fig. 5, a, b. laevigata , through Nodosaria humilis, to N. Badicula.
Fig. 6.
Fig- 7-
EORAMINIEERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 41
Dentalina pauperata, D'Orhrigny. Fragments.
Fig. 8.'
Fig. 9.
Fig. 10. Dentalina communis, JJ Orbigny.
Fig. 11. Dentalina guttifera, I)' Orbigny. A fragment.
Fig. 12, «, b.r
Fig. 13, a , b.J
Vaginulina linearis, Montagu. Fragments.
Fig. 14, a , b. Marginulina Lituus, If Orbigny.
I Cristellaria Crepidula, Fichtel and Moll.
Fig. 16, a , b.J
Fig. 17, a, b.)
Fig. 18, a, b. J
Fig. 19, a, b. Cristellaria rotulata, Lamarck.
Cristellaria cultrata, Montfort.
Fig. 21. Lagena distoma-polita, Parker and Jones.
Fig. 22. Lagena lsevis, Montagu.
Fig. 23. Lagena semistriata, Williamson.
Fig. 24. Lagena sulcata, Walker and Jacob. With spiral narrow riblets.
Fig. 25.1
Fig. 26. >Lagena striatopunctata, Parker and Jones.
Fig. 27. J
Fig. 28, «, b. j
f’ [Lagena sulcata, Walker and Jacob.
Fig. 30, a, b. j
Fig. 31, a, b. }
Fig. 32. Lagena sulcata, Walker and Jacob. Dwarf.
Fig. 33.1
Fig. 34. VLagena Melo, U Orbigny.
Fig. 36. Lagena Melo, JJ Orbigny. Double (monster).
Fig. 37, a, b. Lagena globosa, Montagu.
^’jhagena caudata, P'Orbiqny.
Fig. 39, a, b.J J J
Fig. 40.
Fig. 41.
Fig. 42, a , b.
Fig. 43, a , b
Smooth and entosolenian.
Lagena squamosa, Montagu
1
Fig. 45, a , b.
Fig. 46, «, b.
MDCCCLXV.
Lagena marginata, Montagu.
jPolymorphina lactea, Walker and Jacob.
3k
414 ME, W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Fig. 47, a , b. \
Fig. 48, a , b. J
Fig. 49. 1- Polymorphina compressa, D'Orbigny.
Fig. 50. |
Fig. 51. j
Fig. 52, «, b, c , d. Polymorphina tubulosa, D'Orbigny.
Fig. 53, a , b. 'i
Fig. 54, «, b. |
Fig. 55. !-Uvigerina pygmeea, D'Orbigny.
Fig. 56.
Fig. 57. j
Fig. 58, a, b. Uvigerina angulosa, Williamson.
PLATE XIV. (ARCTIC FORAM1NIFERA.J
[Figs. 1, 2, 14-45 are magnified 12 diameters; figs. 3-13, 24 diameters.
Fig. 1.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fin.
2.
3.
4.
5. #, b.
6. a, b.
7.
8.
9.
10.
11, a, , b.
12.
Globigerina bulloides, D'Orbigny.
Truncatulina lobatula, Walker and Jacob.
|-Anomalina coronata, Parker and Jones.
[Pulvinulina punctulata, D' Orbigny.
JLo, a , 0.)
Fig. 14.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fin.
iPulvinnlina Karsteni, Eeuss.
15, a , b.\
16, a , b. Pulvinulina Micheliniana, D'Orbigny.
17, Pulvinulina Karsteni, Eeuss.
18 1
iDiscorbina obtusa, D'Orbigny.
19, a , b. J
20.
21
■Discorbina globularis, D'Orbigny.
23.,
24. Polystomella crispa, IAnn.
EOEAMINIEEEA EEOM THE NOETH ATLANTIC AND AECTIC OCEANS. 415
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fisr.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
' Polystomella arctica, Parker and Jones.
Polystomella striatopunctata, Fichtel and Moll.
Nonionina asterizans, Fichtel and Moll.
Nonionina Faba, Fichtel and Moll.
j.Nonionina Scapha, Fichtel and Moll.
Nonionina depressula, Walker and Jacob.
0 ’ ^'iNonionina stelligera, I)' Orbigny.
a, , b.\
a, b. Nonionina umbilicatula, Montagu,
a , b. Pullenia sphseroides, If Orbigny.
a , b. Operculina ammonoides, Gronovius.
a, b. Nummulina planulata, Lamarck.
[Fi
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig- 10,
Fig. 11.
Fig. 12.
Fig. 15.
Fig. 16.
Fig. 17.
PLATE XV. (ARCTIC FORAMINIFERA.)
1-33, 36-41, 45-48 are magnified 24 diameters; figs. 34, 35, 42, 43, 44,
12 diameters.]
Cassidulina laevigata, D' Orbigny.
Cassidulina crassa, If Orbigny.
a j jBulimina Pyrula, If Orbigny.
«, b. Bulimina marginata, If Orbigny.
Bulimina aculeata, D' Orbigny.
Bulimina elegantissima, If Orbigny.
6 k 2
416
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Fig. 18. Virgulina Schreibersii, Ozjzek.
Xig. 19, a , ^-lyirgU]jna squamosa, D'Orbigny.
Fig. 20, a, b. J
Fig. 21, a, b. Textularia agglutinans, D'Orbigny.
Fig. 22, a, b. Textularia Sagittula, Def ranee.
•Virgulina squamosa, D'Orbigny.
Fig. 25. Bigenerina Nodosaria, D'Orbigny.
Fig. 26, a, b. Verneuilina polystropha, Beuss.
Fig. 27, a, b. Valvulina conica, Parker and Jones.
Fig. 28. Spirillina rivipara, Ehrenberg.
Fig. 29, a, b , c. Patellina corrugata, Williamson.
Fig. 30. 1
Fig. 31, a , b, cS
j-Trocliammina squamata, Parker and Jones..
Fig. 32. Trochammina gordialis, Parker and Jones.
Fig. 33, a, b. Cornuspira foliacea, Philippi.
Fig. 34. Quinqueloculina oblonga, Montagu.
Fig. 35, a, b. Quinqueloculina Seminulum, IAnne (Vox. triangularis, D’Orb
Fig. 36, a , b. Quinqueloculina Ferussacii, D'Orbigny.
Fig. 37, a , b. Quinqueloculina agglutinans, D'Orbigny.
Fig. 38, «, b. Quinqueloculina subrotunda, Montagu .
Fig. 39, a , b. Triloculina cryptella, D'Orbigny.
Fig. 40, a , b. Triloculina tricarinata, D'Orbigny.
Fig. 41, a , b. Quinqueloculina oblonga? Montagu.
Fig. 42, «, b.' )
Fig. 43, a, b. VBiloculina ringens, Lamarck.
Fig. 44. J
Fig. 45, «, b. Lituola Canariensis, D'Orbigny.
' [-Lituola globigeriniformis, Parker and Jones .
Fig. 47. J
Fig. 48, «, b. Lituola Scorpiurus, Montfort.
PLATE XVI. (NORTH ATLANTIC FORAMINIFERA).
[Tbe figures are magnified 30 diameters.]
Fig. 1. Nodosaria Raphanus, Linne. Dwarf.
Fig. 2, a, b, c. Nodosaria scalaris, Batsch.
Fig. 3. Dentalina consobrina, D'Orbigny. Fragment.
Fig. 4. Cristellaria Crepidula, Fichtel and Moll. Broken.
Fig. 5. Cristellaria cultrata, Montfort.
EORAMINIEERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 417
Eig.
Fig.
Fig.
Fig.
Fig-
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fier.
6. Lagena sulcata, Walker and Jacob. Caudate variety.
7. Lagena caudata, D'Orbigny. Striate.
7, a. Lagena sulcata, Walker and Jacob.
8 1
^ jLagena caudata, D'Orbigny. Smooth.
9, a. Lagena lsevis, Montagu.
10, a, b. Lagena globosa, Montagu.
11, a, b. Lagena squamosa, Montagu.
12, «, b. Lagena marginata, Montagu.
13.1
14.
Drbulina uni versa, D'Orbigny.
15. Globigerina bulloides, D'Orbigny.
jGlobigerina inflata, D'Orbigny.
18, edge view. 1
19, upper view. >Truncatulina lobatula, Walker and Jacob.
20, lower view.J
21, Planorbulina Mediterranensis, D'Orbigny.
22, «, b. Planorbulina Haidingerii, D'Orbigny.
23, upper side.l
24, lower side. ^Planorbulina Ungeriana, D'Orbigny.
25, edge. J
-0, upper side. j^.gco^na Berthelotiana, D'Orbigny.
27, lower side. J J J
"'8, a' uPPer side.j-j^iscorbina rosacea, D'Orbigny.
28, b, edge. J d U
29, upper s^e-|Botalia Beccarii, Linne.
30, lower side. J
31, upper side.l
32, lower side. VRotalia Soldanii, D'Orbigny.
Fig.
Fig.
Fig.
Fig.
Fig.
34, upper view. Rotalia orbicularis, D'Orbigny.
35, upper view.l
36, lower view. >Pulvinulina Menardii, D'Orbigny.
37, edge. J
38, edge. 1
39, upper side. VPulvinulina Karsteni, Ecuss.
40, lower side.J
41, lower side.')
42, edge. iPulvinulina Micheliniana, D'Orb’^ny.
43, upper side.J
418
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
>Pulvinulina elegans, D' Orbigny.
Fig. 44, upper side.-]
Fig. 45, edge.
Fig. 46, lower side.J
Fig. 47, lower side j
Fig. 48, edge i Pulvinulina Canariensis, I)' Orbigny.
Fig. 49, upper side j
Fig. oO. I puiyinulina pauperata, Parker and Jones.
Fig. 51, a,bj
Fig. 52. Sphseroidina bulloides, D'Orbigny.
PLATE XVII. (NORTH ATLANTIC FORAMINIFERA.)
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fie.
[The figures are magnified 30 diameters.]
53. Pullenia sphseroides, D'Orbigny.
54, «, b. Nonionina asterizans, Fichtel and Moll.
55 )
>Nonionina Scapha, Fichtel and Moll.
57, a, b , c. Nonionina turgida, Williamson.
58 )
gg'j-Nonionina umbilicatula, Montagu.
60, «, b. Nonionina striatopunctata, Fichtel and Moll.
61, «, b. Polystomella crispa, Linne.
62, '
63.
Operculina ammonoides, Gronovius.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fig.
Fie.
Fi
!g'
Fi
64, a, b, c. Cassidulina laevigata, D'Orbigny.
64, d. Cassidulina crassa, D'Orbigny.
65, «, b. Uvigerina pygmeea, D'Orbigny.
66, a, b. Uvigerina angulosa, Williamson.
67, a , b. Bulimina ovata, D'Orbigny.
68 )
gg’j Bulimina aculeata, D'Orbigny.
70, «, J, c. Bulimina marginata, D'Orbigny.
71. Bulimina Buchiana, D'Orbigny.
IMvirgulina Schreibersii, Czjzek.
73. ) b J
74. Bolivina punctata, D'Orbigny.
75. Bolivina costata, D'Orbigny.
76. a, b. Textularia abbreviata, D'Orbigny.
77. a , b. Textularia Sagittula, Defrance.
. 78, a , b. Textularia pygmsea, D'Orbigny.
. 79, «, b. Textularia carinata, D'Orbigny.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 419
Fw
Fig,
F
F
F
F
F
F
F
Fig
is1. 80,
81.
lg. 82.
83,
84.
85,
86, a, b.
87.
88.
89,
a, b. Bigenerina Nodosaria, L'Orbigny.
Bigenerina digitata, L'Orbigny.
Spirolocalina planulata, Lamarck,
a, b. Spiroloculina limbata, L'Orbigny.
Quinqueloculina tenuis, Czjzek.
° ' ^Quinqueloculina oblonga, Montagu.
Quinqueloculina Seminulum, Linne.
Biloculina elongata, L'Orbigny.
a, b. Biloculina depressa, L'Orbigny.
Fig.
90.)
Fig.
91./
Fig.
92.
Fig.
93.
Fig.
94.
Fig.
95. ,
Fig.
96. |
Fig.
97.
Fig.
98. J
Biloculina elongata, L'Orbigny.
Lituola Canariensis, L'Orbigny.
L.
Lituola globigeriniformis, Parker and Jones.
PLATE XVIII. (MISCELLANEOUS FORAMINIFERA.)
[Figures 15-18 are magnified 30 diameters; all the rest are magnified 60 diameters
(excepting fig. 6 b, 200 diameters.)].
Fig. 1, a, b. Lagena trigono-marginata, Parker and Jones. A rare form, from the inside
of an Eocene Tertiary shell from Grignon*. It is an isomorph of the tri-
gonal Nodosarince. See page 348.
Fig. 2, a, b. Lagena squamoso-marginata, Parker and Jones. Living on the Coral-reefs
of Australia (Jukes) ; fossil in the Middle Tertiary beds of San Domingo.
See page 356.
Fig. 3, a, b. Lagena radiato-marginata, Parker and Jones. Bare. Recent, Australian
Coral-reefs (Jukes) ; fossil, Middle Tertiary, Bordeaux. See page 355.
* This Lagena, as well as the other Grignon specimens on this plate, together with Discorbina globigerinoides
on Plate XIX., and many other Foraminifera, were obtained from the inside of a Cerithium giganteum ; and, as
a group, they differ from those got by us from any other sample of the Calcaire grossier, in their extreme
freshness and their minute size. The Australian seas supply a Foraminiferal fauna very analogous to that of
Grignon (fossil) ; and that of the northern part of the Red Sea (300-600 fathoms) corresponds in many respects
to that shown by the contents of the fossil shell referred, to. The Ceritliium itself would not, of course, indicate
any such depth as that above mentioned ; but the analogy of the fossil and recent faunae under notice is cer-
tainly striking. Still, the smallness of some of the forms amongst those from the Red Sea, and the absence of
Polyzoa and of small Gasteropoda and Lamellibranchs in these soundings (replaced by abundance of small
Pteropods), sufficiently separate the two.
420
MR. W. K. PARKER AND PROEESSOR T. R. JONES ON SOME
Fig. 4, ft, b. Lagena crenata, Parker and Jones. Eare. Eecent, shore-sand at Swan
Eiver, Australia; fossil, Middle Tertiary of Bordeaux and Malaga. The
figure well shows the characters of this pretty Lagena. Decanter-shaped;
neck long and coiled ; body gradually widening and smooth to the base, which
for half its radius is widely and deeply crenate with broad radiating furrows ;
the centre of the base being smooth and gently convex.
Fig. 5. Lagena distoma-aculeata, Parker and Jones. Eare. Fossil at Grignon. Iso-
morphous of prickly Nodosarince. See page 348.
Fig. 6, a, b. Lagena distoma-margaritifera, Parker and Jones. Eecent, from the surf-
washed sponges at Melbourne, Australia. See page 357.
Fig. 7, «, b. Lagena tubifero-squamosa, Parker and Jones. Fossil at Grignon. This
very large globular Lagena , with a distinct and ramifying neck, has shallow
honeycombings and a very thick shell, the outer layers of which decaying
leave a very smooth, thin Lagena , ordinary-looking except for its neck. See
page 354.
Fig. 8. Lagena distoma-polita, Parker and Jones. A large, smooth, two-mouthed, fusi-
form Lagena , from the Eed Sea and Australia. See page 357.
Fig. 9, a, b. Lagena lsevis, Montagu. A double individual (monster). Fig. 9 b is a
section. Eare. Eecent, from the English Channel at Eastbourne. See page
353.
Figs. 10, 11. Lagena Isevis, Montagu. Monstrous Lagence , double by lateral growth.
Fossil, Grignon. See page 353.
Fig. 12, ft, b. Lagena lsevis, Montagu. Monstrous bilobed specimen. Fossil: Grignon.
See page 353.
Fig. 13. Nodosaria scalaris, Batsch. For comparison with figs. 9 ft, 9 b. Seepages 340
and 353.
Fig. 14, ft, b. Lagena tretagona, Parker and Jones. A rare, delicate, feeble form of L.
striatojmnctata w7ith four ridges and surfaces. Fossil: Grignon. See page 350.
Fig. 15. Uvigerina (Sagrina) nodosa, POrbigny. See page 363.
Figs. 16, ft, b , & 17. Uvigerina (Sagrina) Eaphanus, Parker and Jones. Eecent: West
Indies, Panama, India (on Clam-shell), Bombay Harbour (anchor-mud), Hong
Kong (anchor-mud), Australian Coral-reefs (17 fathoms). See page 364.
Fig. 18. Uvigerina (Sagrina) dimorpha, Parker and Jones. Eecent: Eed Sea (near the
Isle of Shadwan, at 372 fathoms), Abrohlos Bank (260 fathoms), Australian
Coral-reefs (17 fathoms). See page 364.
Fig. 19. Textularia Folium, Parker and Jones. A very thin Textularia , with linear
chambers, usually very unequal in their length, and forming a flat, pectinated,
irregularly triangular or subrhomboidal shell, seldom so symmetrical in shape
as the figured specimen. Shore-sand near Melbourne. See page 370.
FOB A MINIFEE A FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 421
PLATE XIX. (MISCELLANEOUS FORAMINIFERA.)
[Figures 2 & 3 are magnified 15 diameters; figs. 1, 4-13, 25 diameters (excepting
fig. 5 c, 25 diameters.)].
Fig. 1. Planorbulina Culter, Parker and Jones. Very rare. Tropical Atlantic (1080
fathoms). A neat, discoidal, biconvex, trochiform Planorbulina, showing on
its upper face about twenty-five (often more) neatly set chambers in a compact
spire, bordered with a thin keel, as wide as a whorl of the chambers. It is an
extreme varietal condition of the subsymmetrical form, imitating Pulvinulina,
and ought to have been noticed at page 379, as a starved PL TJngeriana.
Fig. 2. Planorbulina retinaculata, Parker and Jones. Parasitic on Shells, East and
West Indies. See page 380.
Fig. 3, a, b. Planorbulina larvata, Parker and Jones. Indian Sea. See page 380.
Fig. 4, a, b. Pullenia obliquiloculata, Parker and Jones. Abrohlos Bank (260 fathoms),
Tropical Atlantic (1080 fathoms), Indian Ocean (2200 fathoms). See page 368.
Fig. 5, a, b, c. Sphseroidina dehiscens, Parker and Jones. Fig. 5 c, fragment of shell-
wall more highly magnified. Tropical Atlantic (1080 fathoms) and Indian
Ocean (2200 fathoms). See page 369.
Fig. 6, a, b, c. Discorbina rimosa, Parker and Jones. Recent : India (on Clam-shell).
Fossil: Tertiary, at Grignon, Hautville, Freville, La-Fosse-de-Launy, &c. (Sir
C. Lyell’s Collection). This is smaller than 1). vesicularis, and close to it and
D. elegans in alliance ; somewhat oval in shape ; shell-substance thick, pores
large ; septal plane notched for aperture ; chambers very much larger in the
newer than in the older part of the shell, and discrete ; and on the upper side
several of the newer chambers are separated by chinks. On the under side
there are secondary chambers over the umbilicus, perfect, large, and astral,
with chinks at their periphery. See page 385.
Fig. 7, a, b, c. Discorbina globigerinoides, Parker and Jones. Common in the Calcaire
grossier of Grignon. This Discorbina equals in size fine Tropical Globigerince,
and reminds one of their form. It is also isomorphous with Cyrnbalopora
bulloides, D’Orb., sp. In appearance it is the very opposite of its real ally
D. Parisiensis ; but it has much the same kind of septal face, the inner two-
thirds of which are thickly covered with sinuous wrinkles and granules of
exogenous shell-matter, having large pores opening out of them, and thus
presenting a rudiment of the canal-system. A similar thickened surface, but
formed of radiating granules, on the under side of the shell, is seen in D. ob-
tusa, D’Orb., and D. Parisiensis , D’Orb. LThe astral processes in D. globigeri-
noides are abortive. See page 385.
Fig. 8, a, b, c. Discorbina polystomelloides, Parker and Jones. From the Australian
Coral-reefs (Jukes’s dredgings). This may be said to be a granulose form of
mdccclxv. 3 l
422
MR. W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
D . rimosa ; but it is larger, more symmetrical, and extremely rough ; and the
chinks between the chambers are partly bridged over, so as to form a rough
canal-system, as in some of the Polystomellce.
Fig. 9, a , b , c. Discorbina dimidiata, Parker and Jones. Large and profusely abundant
among the surf-washed Sponges on the Melbourne coast. This is merely D.
vesicularis modified by being sharp-edged, and flat, and even scooped on the
under face (opposite to that which is flat in Truncatulina). The astral flaps
or valves are strongly marked over the umbilicus. See page 385.
Fig. 10, a , b, c. Discorbina biconcava, Parker and Jones. Shore-sand, Melbourne. A
very small isomorph of Planulina Ariminensis. It is a hyaline, thick, lim-
bate, square-edged, biconcave Piscorbina, most concave on the umbilical face
(as usual with the genus). Its astral flaps are feeble. See page 385.
Fig. 11, a, b, c. Lot alia annectens, Parker and Jones. Hong Kong (anchor-mud) and
Fiji (coral-reef). A well developed Conus-shaped Botalia, which has, on its
under or umbilical surface, partially formed secondary chambers, owing to
angular processes of the septa nipping the umbilical lobes. It is thus a pas-
sage-form between B. Schrceteriana, P. & J., and B. ( Asterigerina ) lobata,
D’Orb. See page 387.
Fig. 12, a, b, c. Lotalia craticulata, Parker and Jones. Fiji. This Polystomelloid Bo-
talia is noticed by Dr. Carpenter, Introd. Study Foram. p. 213. See page 387.
Fig. 13, a, b , c. Rotalia dentata, Parker and Jones. Bombay Harbour (anchor-mud).
A well-grown, biconvex Botalia , with numerous subquadrate chambers,
thickened and raised septal edges, rowelled margin, and massive umbilicus.
See page 387.
Appendix I. — Additional North Atlantic Foraminifera.
The Rev. J. S. Tute, of Markington, has shown us a set of carefully executed drawings
of minute Foraminifera from 67 fathoms, Atlantic Soundings, belonging to the Rev.
W. Fowler, of Cleckheaton. These comprise
Globigerina bulloides.
Spirillina vivipara.
Planorbulina lobatula.
Ungeriana.
Textularia pygmsea.
Miliola (young).
Also
Pteropoda ( CuvieriaX and InmacinaX).
Among the above, Spirillina vivipara is additional to our list of Foraminifera from
the Atlantic Soundings. See also page 368.
With reference to very minute Foraminifera, such as are here referred to, it may be
Tram. 1S65. To face page 422.
TABLE VIL Table op the Nobth Atlastic asd Arctic Fobamisifeba, with theie distbibutios is otheh Seas.
[For the completion of the Fauna of each of these localities, excepting Nos. 5, 11, 12, 13, & 25, which are here complete, see Appendix VI.]
rl. Bather large. m. MHdle-sizeA ». Small. w. Veiy mnalL VC. Very common. C. Common. EC. Rather common. IUl. Rather rare. II. rare. VK. Very rare.
FORAMINIFERA FBOM THE NORTH ATLANTIC AND ARCTIC OCEANS. 423
observed that wherever Foraminifera are abundant small individuals are plentiful, but
they very rarely represent other types than those to which the larger specimens are
referable.
Appendix II. — Professor J. W. Bailey’s Researches on the “ Virginian ” Foraminifera
of the North Atlantic.
“ Microscopical Examination of Soundings made by the U. S. Coast-survey off the
Atlantic Coast of the U. S. By Professor J. W. Bailey,” Smithsonian Contributions
to Knowledge, vol. ii. 1861, Article III. *
The examination was made and reported in 1848. The soundings were taken off the
coast of New Jersey and Delaware, from lat. 50° to lat. 38° N., varying in depth from
10 to 105 fathoms. In the deeper soundings Professor Bailey found “ a truly wonderful
development of minute organic forms, consisting chiefly of Polythalamia” (Foraminifera).
He also remarked that these deep soundings were from a sea-hed under the influence,
more or less, of the Gulf-stream ; and that probably this might cause an immense deve-
lopment of organic life — giving rise to a “ milky way of Polythalamia.” Professor
Bailey also noticed that Foraminifera abundant in deep water would necessarily there
make extensive calcareous deposits, contrasting with the quartzose and felspathic sands
and muds of the coast.
We will, in the first place, give abridged notices of those soundings which were found
to contain Foraminifera ; and afterwards we will offer some remarks on Prof. Bailey’s
specific determinations, adapting them to the nomenclature used in this monograph, and
so make them available for comparison with our “ Celtic” forms.
E. No. 37. About South-east of Montauk Point ; lat. 40° 59' 55", long. 71° 48' 55" :
19 fathoms. Coarse gravel, mingled with ash-coloured mud. With a few small Fora-
minifera, chiefly Botalina ; a small bivalve Crustacean, Biatomacece, and Sponge-spicules.
E. No. 9. Lat. 40° 21' 54", long. 70° 55' 35" : 51 fathoms. Greenish-grey mud or fine
sand, with a few bits of shells, and a considerable number of Foraminifera , among which
were Marginulina Bachei , Bailey (fig. 5, not abundant), Bobulina D'Orbignii, Bailey
(figs. 9 & 10), and Bulimina auriculata, Bailey (figs. 25-27).
F. No. 27. About South-east of Fire Island Inlet; lat 40° 14' 13", long. 72° 21' 30":
20 fathoms [material not described]. One specimen of Quingueloculina occidentalism
Bailey (figs. 46-48) ; with a spine of Echinus and small plates of an Echinoderm.
F. No. 24. Lat. 39° 52' 40", long. 72° 14': 49 fathoms. Greenish grey, rather coarse
sand, mixed with some mud. Foraminifera rather abundant, comprising Marginulina
Bachei , Bailey (fig. 5, rather common), Orbulina universa, D’Orb. (fig. 1, rare), a small
Bulimina, a few small specimens of Globigerina ; also a few Sponge-spicules, a small
Cypridiform Crustacean shell, and a spine of Echinus.
* As tliis memoir is referred to by Professor Bailet in the Am. Journ. Se. Arts, March 1854, it was in print
long before 1861,
3 l 2
424
MR. W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
F. No. 25. Lat. 39° 41' 10", long. 71° 43': 105 fathoms. Fine greyish-green sand,
very rich in Foraminifera , especially in Globigerina (tigs. 20-22, Gl. infiata , D’Orb.),
with Marginulina Bachei, Bailey (fig. 5, rare), and Textularia Atlantica, Bailey (figs.
11-13, common); also Sponge-spicules and Diatomacece .
G. No. 27. About East from Little Egg Harbour ; lat. 38° 4F, long. 76° 6' : 20 fathoms.
Fine-grained sand with black specks. A few fragments of bivalve and univalve Shells,
small spines and numerous plates of an Echinoderm, and some Foraminifera : Trilocn *
Una Frongniartiana, D’Orb. (figs. 44, 45), Bobulina D'Orbignii , Bailey (figs. 9,10, rather
common), and several specimens of a minute species of Botalina (1) ; also Diatomacece .
G. No. 31. Lat. 39° 20' 38", long. 72° 44' 35" : 50 fathoms. Fine-grained greyish sand
with much mud. A considerable number of 'including Marginulina Bachei ,
Bailey (rather common), Bobulina D'Orbignii, Bailey (figs. 9, 10), and Globigerina rubra ,
D’Orb. (common; but not so common as in F. No. 25); also Diatomacece and some
Sponge-spicules.
G. No. 8. Lat. 39° 31', long. 72° 11' 20": 89 fathoms. Sand, coarser than the last,
not so muddy, and about the same colour. Abounding in Textularia Atlantica, Bailey
(figs. 38-43), and in Globigerince (figs., 20-24, Gl. infiata and Gl. bulloides), and also
containing Marginulina Bachei , Bailey, Bobulina D'Orbignii, Bailey, and Orbulina uni-
versa, D’Orb., together with a few Diatomacece and Sponge-spicules.
H. No. 2. South-east from Cape Henlopen ; lat. 38° 46' 40", long. 75° 00' 30": 10
fathoms. Fine sand, slightly muddy. One specimen of Triloculina and a few minute
nautiloid Foraminifera ; together with a great variety of Diatomacece, some Sponge-spi-
cules, and a few small spines of an Echinoderm.
H. No. 17. Lat. 38° 29' 56", long. 74° 38' 4": 20 fathoms. Clean quartzose sand,
coarser than the last, white and yellow, with black specks. Many Diatomacece , but no
evidences of Foraminifera except their soft parts, retaining the form of the chambers.
H. No. 67. Lat. 38° 9' 25", long. 74° 4' 5": 50 fathoms. Clean greyish sand, con-
taining a few minute Globigerince and Botalince ; also Diatomacece.
H. No. 1. Lat. 38° 4' 40', long. 73° 56' 47": 90 fathoms. A rather coarse grey sand,
with some mud, containing a few Diatomacece and a vast number of Foraminifera,
“ particularly Globigerina, many thousands of which must exist in every inch of the sea-
bottom at this locality.” The following were also common here : — Orbulina universa ,
D’Orb. (fig. 1), Marginulina Bachei, Bailey (figs. 2-6), Bobulina D'Orbignii, Bailey (figs.
9, 10), Botalina Ehrenbergii, Bailey (figs. 11-13).
Professor Bailey described and figured nearly, if not quite, all the different forms of
Foraminifera that he met with in his examination of these soundings, — also some of the
Diatoms and Sponge-spicules, as well as some minute spherical calcareous bodies, occur-
ring either singly or united in strings and bunches (transparent when mounted in balsam),
which he' thought might possibly be ova of Foraminifera, but which we believe to be
little inorganic crystalline globules of calcite, common in many sea-beds. The calcareous
granules he found abundantly at 90 fathoms, and at 105, 89, and 20 fathoms.
EOEAMINIEEEA FEOM THE NOETII ATLANTIC AND AECTIC OCEANS. 425
The allusions to the Foraminifera in the Soundings “E. No. 37,” “ H. No. 2,” and
“H. No. 67,” are not precise enough for the determination of the species found therein ;
and even with the notes appended to the account of the Species, we cannot make a very
exact table of the distribution.
In Professor Bailey’s plate illustrating his memoir, we have
1. Orbulina universa , D’Orb., tig. 1.
2. Nodosaria , a fragment, tig. 8. With almost cylindrical chambers, as in some sub-
varieties of N. Pyrula , D’Orb. Several fragments in the deeper soundings are said to
have occurred.
3. Dentalina mutabilis , Bailey, tig. 7. This fragment might well belong to such a
subvariety of Dentalina communis as D. pauperata, D’Orb. Several fragments were
found in “FI. No. 1.”
4. Marginulina Racliei, Bailey, tigs. 2-6. Figs. 2-4 are the same as If. similis, D’Orb.,
and M. pedum, D’Orb., all of these being dimorphous or Marginuline modifications of
Nodosaria Rctdicula, Linn., sp„ ; and figs. 5, 6 represent a larger individual of the same
form, such as has been named Marginulina regularis by D’Orbigny in his ‘ Foram. Foss.
Bassin Vienne,’ where the others are figured.
5. Robulina D’Orbignii , Bailey, figs. 9, 10. This is the common Cristellaria cultrata,
Montfort, sp. The figured specimen has its last few chambers keelless, and trying, as
it were, to leave the discoidal plan of growth, each having its septal aperture almost free.
This is said to accompany the foregoing, which was in considerable numbers in all
except the shallow soundings.
6. Rotalina Rhrenbergii , Bailey, figs. 11-13. This is Planorbulina Haidingerii , D’Orb.,
sp. (a variety of PL far eta, Fichtel and Moll, sp.), and occurred in “ F. No. 25.” and in
several of the deeper soundings. Professor Bailey thought it to be near Rotalia Soldct-
nii , D’Orb. ; and in truth Pl. Haidingerii does resemble that form, — but as an isomorph,
not as a relative : so also it is an isomorph of Pulvinulina truncatulinoides, D’Orb.
7. Rotalina cultratal , D’Orb., figs. 14-16. This is the common Pulvinulina Menar-
dii , D’Orb., a variety of P. repanda , Fichtel and Moll, sp. Deferred to as common in
the deeper soundings.
8. Rotalina semipunctata , Bailey, figs. 17-19. The same as Planorbulina Ungeriana,
D’Orb., sp. ( Pl.farcta , var.).
9. Globigerina rubra , D’Orb., figs. 20-24. Professor Bailey rightly considered figs.
20-22 to represent a separate form; it is Gl. inflata , D’Orb., a variety of Gl. bulloides ,
D’Orb., to which all must be referred specifically, D’Orbigny’s GL rubra being so named
on account of the ruddiness of its shell, which is not dependent on the sarcode for its
pink colour. GL inflata is specially noticed as occurring at 105 fathoms. Vast num-
bers of Globigerina occurred in the deeper soundings, especially the deepest ; whilst they
were but few and small at 49 fathoms. “ The abundance in which the species of Globi-
gerina occur in the deep soundings G„ No. 31 and H. No. 1 gives to these green muds a
most striking resemblance to the green Tertiary marls perforated by the artesian wells
426
ME. W. K. PAEKEE AND PEOPESSOE T. E. JONES ON SOME
at Charleston, S. C. This similarity appears to indicate that the Charleston beds were a
deep-sea deposit, perhaps made under the influence of an ancient Gulf-stream” (p. 11).
10. Bulimina auriculata, Bailey, figs. 25-27. This is B. Pyrula , D’Orb. Several found
at 51 fathoms.
11. Bulimina turgida, Bailey, figs. 28-31. A slight modification of B. Pyrula , D’Orb.,
the newer chambers being proportionally large and overlapping. It occurred with the
foregoing, and at 49 fathoms.
12. Bulimina serrata , Bailey, figs. 32-34. The very small Bulimina ( Virgulina) Schrei-
hersii, Czjzek.
13. Bulimina compressa , Bailey, figs. 35-37. The same as B. ( Virgulina ) squamosa,
D’Orb.
14. Textularia Atlantica , Bailey, figs. 38-43. This is the Textularia ( Verneuilina) tri-
quetra , Munster ( Verneuilina tricarinata, D’Orb.). Found by Professor Bailey only in
the deeper soundings ; especially abundant at 89 fathoms (“ G. No. 38 ”). (Judging
from our own specimens, we think that in these figured specimens the aperture of the
shell is drawn too smoothly.)
15. Triloculina Brongniartii , D’Orb., figs. 44, 45.
16. Quinqueloculina occidentals, Bailey, figs. 46-48. This fair typical form of Miliola
( Quinqueloculina ) Seminulum , Linn., sp., is said by Professor Bailey to occur “not
uncommonly in the sands along the western shores of the Atlantic,” — as indeed it does
along many coasts.
In presenting the annexed bathymetrical Table (No. VIII.) of Professor Bailey’s
Foraminifera, we must express a hope that some day a fuller Synopsis of this marginal
Fauna of the “ Virginian Province ” will be produced by the Transatlantic naturalists
from more ample materials than Professor Bailey had to work on ; for we cannot think
that this Fauna is fully represented by the present list.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS.
427
Table VIII. — Table of the Foraminifera of the “ Virginian Province.”
(After Professor Bailey; with Nomenclature corrected.)
Genera, Species, and Varieties.
Fathoms . .
1
H. 2* * * §.
o o
^ CO
CD ©
o o
QO tO
CO J>
-+i pi
cS o
1-4 h4
10.
2
E. 37+.
© Co
io »o
Cl 00
to
o o
© r-l
. 60
a o
i-4 1-4
19.
3
F. 27.
CO o
1-H CO
rH Sq
© oq
1-
. &i>
31
20.
4
G. 27+
§0 ©
CO I -
. 6c
cS O
i-4 1-4
20.
5
F. 24.
O O
hH
O rH
o o
OS CM
CO t -
. z>£>
& O
^ ^ ;
49.
6
G. 31.
00 IQ
CO CO
O
CM hH
os oq
CO l -
. 6C
M
50.
7
H. 67§.
to to
<M
OS ^
o o
00
CO b-
. E®
o
h4 t-4
50.
8
E. 9.
^ io
to CO
r4 tb
cq to
o o
o o
Ttl t"
bh
PI
c3 O
i-4 i-4
51.
9
G. 8.
CM
CO rH
os oq
CO b-
. cb
n
cS o
i-4 f-4
89.
10
H. 1.
^ CD
IO
00 §0
CO b-
•
P4h3
90.
11
F. 25.
© ©
4-i co
rK
OS 2-1
CO
. 60
Pi
r: o
1-4 i-4
105.
Orhulina universa, D’O
*
*
*
Nodosaria Pyrula, D’O
9
9
9
9
?
9
Dentalina communis (pauperata), D’O. ....
*
Marginulina regularis, D’O
*
*
*
*
*
*
Cristellaria cultrata, Montf.
*
9
*
*
*
*
9
Planorhulina Haidingerii, D’O
*
9
9
9
9
*
Ungeriana, D’O
*
Pulvinulina Menardii, D’O
9
9
9
9
9
9
Globigerina bulloides, D’O
*
*
*
*
*
*
Bulimina Pyrula, D’O
*
*
(Virgulina) Schreibersii, Czjzek
*
*
( ) squamosa, D’O
*
*
*
Textularia (Verneuilina) triquetra, Miinst. . .
9
*
*
*
Triloculina Brongniartii, D’O
*
*
Quinqueloculina Seminulum, Linn
*
Diatomaeese
*
*
*
*
*
*
*
*
Sponge-spicules
*
*
*
*
*
Eehinodermata
*
*
*
*
Mollusca (fragments of shells)
*
*
Bivalved Entomostraca
*
*
* Containing “ a few minute nautiloid Eoraminifera ” besides tbe Triloculince.
t A few small Foraminifera, chiefly “ Rotalina,’1 were found in this soundiDg.
X Also containing “ a minute species of Rotalina.”
§ Containing a few minute Globigerince and Botalince.
428
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Appendix III. — Further Researches by Professor J. W. Bailey.
“ Examination of Deep Soundings from the Atlantic Ocean.” By Professor J. W.
Bailey, of West Point, New York,” American Journal of Science and Arts, 2 ser.
vol. xvii. p. 176, &c. 1854.
In this memoir Professor Bailey describes the results of his examination of five deep-
sea soundings, from the Atlantic, given him by Lieut. Maury, and of one sounding, of
less depth, made by Lieut. Berryman.
Fathoms.
1. 1800
(Lat. 42° 04'|
N. of the Azores.
(Long. 29° 00'j
I860 ip1' ILn.E. of the Azores.
(Long. 24 35 j
49° 56' 30") ,T . ,
1580{Long.l3°13'45»}S'W'OfIreland-
isoof
2000
Lat. 47° 38
{Long. 09° 08
Lat. 54° 17'
Long. 22° 33;
Lusitanian Province.”
Off the mouth of English Channel, y “ Celtic Province.’
W. of Ireland.
These soundings contained no gravel, sand, or other recognizable inorganic mineral
matter, but consisted of Foraminifera and calcareous mud derived from their disintegrated
shells. Globigerince greatly predominated; and Orbulince were in immense numbers in
some, especially in the sounding from 1800 fathoms. They all contained Fiatomacece ,
Sponge-spicules, and Folycystinoe. Professor Bailey remarked that Agatliistegia ( Miliola ,
&c.) were absent, as well as Marginulina , Textularia , and other forms that he had met
with in shallower soundings.
II. Lieutenant Berryman’s Sounding.
Fathoms. [ Lat. 42° 53' 30" N.
17&‘ | Long. 50° 05' 45" W.
S.S.E. of Newfoundland. On northern border of the
“ Virginian Province ” (the western extension of the
“ Celtic Province ”).
The sea-bed off Newfoundland is here destitute of Foraminifera as far as this sounding
shows ; the quartzose sand, with a few grains of hornblende, being barren of shells or
other organic remains.
Professor Bailey’s results in these examinations are therefore very similar to those
obtained by ourselves from similar parts of the Atlantic bed.
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 429
Appendix IV. — Researches on the North Atlantic Foraminifera ,
by F. L. Pourtales, Esq.
“ Examination (by F. L. Pourtales, Esq., Assistant in the United States Coast-survey)
of Specimens of Bottom obtained in the Exploration of the Gulf-stream, by Lieutenants
Commanding, T. A. M. Craven and J. N. Maffitt, United States Navy,” Report of the
Superintendent of the United States Coast-survey for 1853; Appendix, No. 30, pages
82*, 83*, 1854.
From fourteen soundings off the eastern coast of Florida, and three off Georgia (all
belonging to the “ Caribbean Province”), Count F. Pourtales obtained results similar
in a great degree to those of Professor Bailey’s examination of the soundings off New
Jersey and Delaware (see above, page 423) ; and having soundings from much greater
depths (150 to 1050 fathoms), he met with a greater predominance of Globigerina?,
forming, with other Foraminifera, the white mud of the sea-bed ; in one instance Globi-
gerince and the minute green stony casts of these shells entirely formed the bedf (at
150 fathoms, lat. 31° 2', long. 79° 35'). At 1050 fathoms (lat. 28° 24', long. 79° 13')
he found Globigerina and Orbulina, and the so-called Rotalina cultrata , R. Ehrenbergii,
and R. Bayleyi , with fragments of Molluscan Shells, of Corals, and of Anatifer , as well as
some Pteropoda; and only about 1 or 2 per cent, of fine sand in the Foraminiferal mud.
As these soundings are beyond the limits of the “Provinces” that we have to do with
in the foregoing memoir, we omit the details of the other specimens of the “ Caribbsean”
sea-bed ; but we remark that the author of this notice refers to former Reports (and
Proc. Amer. Assoc. Charleston) in which he had intimated that “ with the increase in
depth — in the greater depths — the number of individuals [of Foraminifera , especially
Globigerina ] appeared to increase,” having then seen a sounding from 267 fathoms where
the sand contained 50 per cent, of Foraminifera ; whilst now he found at upwards of
1000 fathoms Foraminifera with little or no sand. The extension of life to greater
depths than 300 fathoms (E. Forbes, iEgean, Brit. Assoc. Rep. 1843) is also noticed by
the author ; but his suggestion, that Globigerina would be found to decrease gradually
“ for a considerable depth before it should cease to appear,” does not appear to be as
yet substantiated, since Globigerina holds its own at the greatest depth (2700 fathoms,
South Atlantic) hitherto experimented upon. He remarks that the Foraminifera
appear to be fresh in the deep-sea soundings, and probably live at the great depths from
which they are brought up.
Note. — Maury has already observed that the bed of the Atlantic at more than two
miles depth has no sand nor gravel, but consists chiefly of Foraminifera and a small
number of Diatomacece (siliceous). — “ Sailing Directions,” &c., 6th edit. 1864.
f To this Professor Bailey refers in his interesting paper “ On the Origin of Greensand and its formation in
the Oceans of the present Epoch,” Quart. Journ. Microscop. Science, vol. y. pp. 83-87 ; 1857.
3 M
MDCCCLXV.
430
MR. W. K. PARKER AND PROFESSOR T. R. JONES ON SOME
Appendix V. — The Foraminifera of the “ Celtic and Virginian ” Provinces of the North
Atlantic , as a Fauna.
The accompanying Table (No. IX.), already alluded to atp. 332, gives us a synoptical
view of the Foraminifera of the “ Celtic Province,” including its western or “ Virginian”
portion. Excepting that further research will enrich the “ Virginian” columns (Coralline
and Coral zones of the American side of the Province), the Table comprises a complete
Foraminiferal Fauna; and we believe that, by careful condensation of the multitudinous
varietal forms under specific heads, we have fairly indicated the range and relative
abundance of the members of a natural-history-group under such local conditions as
naturalists have determined, chiefly by the aid of Mollusca and other marine animals,
to belong to a more or less uniform zoological area.
Professor Williamson’s ‘Monograph of the British Recent Foraminifera’ has (with
corrections of nomenclature) supplied the first column, for the Littoral, Laminarian,
Coralline, and Coral zones; Mr. H. B. Beady’s researches in the Shetland and other
British Foraminifera give us the second column; the next four columns refer to the
different parts of the North Atlantic from whence we have many of the Foraminifera
described in this memoir; and the last two columns comprise what we know of the
“ Virginian” Foraminifera, to which the Appendices Nos. II., III., & IV. have reference.
FORAMINIFERA FEOM THE NORTH ATLANTIC AND ARCTIC OCEANS. 431
Table IX. — Table of the Foraminifera of the “ Celtic Province,” including the North-American
or “ Virginian ” portion of that Province.
Note. — Mr. H. B. Beady has kindly aided us in. making the first two Columns as complete as possible.
1
■ s
^ J
^ o -
a • a
O ."tn
2
ri i zq
w 5q £
o j§
rT1'4J C3
O ^ . Q
North Atlantic [Coral-zone]
(43-90 fms.); off the Irish coast. °°
r
North Atlantic ; Deep Water of the
Eastern Plateau (200-400 fms.). ^
it
Abyssal Depths
76 fms.).
Abyssal Depths
ns.), “Boreal o
nee.”
1 c<V- • • -I
“ Virginian
> Province ”
j (after Bailey). ^
Gexeba, Species, aed Yaeieties.
Fathoms ...
m ^
lit
MS
3
Coral-zone [50-10
Isles ; representi
land Fauna (Mr. H
of 60-8
North Atlantic ;
(1 750-2 r
o °
’ g c? Ph
o w
CD •
a o
O crj
o ^
^ o
o t-H
X
h©1 m
g a
ri
co O
O I
1 —
'sr
0-80.
43-90.
200A0a
1750^2176.
1450-^2350.
10-20.
49-105.
•1450-
4
r~
-2350.
Lagena sulcata type
r
*
*
*
r lsevis
*
*
semistriata
*
*
r striata
*
*
distoma subtype
*
*
(Entosolenia) globosa
*
*
*
( ) caudata
*
*
*
( ) marginata
-*
-*
-*
*
( ) squamosa
*
*
( ) Melo
*
*
Nodosarina (Glandulina) laevigata
*
(Nodosaria) scalaris
*
*
*
( ) Pyrula
*
*
*
( ) Raphanus subtype
*
*
*
(Lingulina) carinata
*
(Dentalina) communis (and subvarieties)
*
*
*
*
( ) Acicula
*
*
(Vaginulina) linearis
*
(Cristellaria) cultrata and rotulata ....
*
*
*
*
( ) Crepidula
*
*
%
( ) Italica
*
(Marginulina) Lituus
*
( ) regularis
*
Polymorphina lactea type
*
*
compressa
*
*
tubulosa
*
-*
concava
*
myristiformis . . .
*
-*
TJvigerina pygmsea
*
*
**
angulosa
*
*
*
irregularis
Orbulina universa type
*
*
*
. **
9
*-
Globigerina bulloides , fyp„
*
*
**
. ***
***
?
Sphaeroidina bulloides ....
*-
Pullenia sphseroides
*
*
Textularia Sagittula
*
Trochus
%
variabilis
%
abbreviata
*
pygmsea
*
*
*
"
*
6 M
432
ME. W. K. PAEKEE AND PEOFESSOE T. E. JONES ON SOME
Table IX. (continued).
1
rd
d
c3 03
^ O
o •
.S m d
5=1 rd S
1:3 §
°(Sii
2
p . ^
•2 A oc
cm © ^
»•
rwa
O “ « O
; [Coral-zone]
F the Irish coast. 05
leep Water of the
(200-400 fins.). ^
5
j|
Hi
<D
P
1 fl
Abyssal Depths
ns.), “ Boreal a
ce.”
7
a -
.Sc
•it
8
5
5|
Genera, Species, and Varieties.
Fathoms ...
‘S 8 j5
’S O C3
g ? t>>
1—1 ®
ra'^ '■%
p
Coral-zone [50-10
Isles; represen
land Fauna (Mr. H
l of 60-8
o
n ^
£ o
r
North Atlantic; I
Eastern Plateau
.J5?
g S
North Atlantic ;
(1450-2350 fr
Provin
f [Coralline zone]
^ (10-20 fins.).
[Coral-zone]
(49-105 fins.). J
0-80.
A.
434)0.
200^400.
17504U76.
1450-2350.
10-20.
49-105.
V
1450-2350.
/
Textularia carinata
difformis
*
*
complexa
*
(Verneuilina) polystropha
*
*
( ) triquetra
**
— — (Bigenerina) digitata
*
( ) Nodosaria
*
**
Bulimina pupoides
*
*
Pyrnla
*
Buchiana
*
marginata
*
*
**
*
aculeata
*
*
*
ovata
*
*
*
*
convoluta
*
*
(Robertina) elegantissima
*
*
(Virgulina) Schreibersii . .
*
*
-*
*
*
( ) squamosa
*
(Bolivina) punctata
*
*
*
( ) costata
*
*
Cassidulina ltevigata type
*
*
**
*
*
crassa
*
*
*
Spirillum vivipara type
*
*
margaritifera
*
Discorbina rosacea
*
*
*
ochracea
*
*
globularis
*
*
Berthelotiana
*
*
Planorbulina Mediterranensis
*
*
Haidingerii
*
*
Ungeriana
*
*
*
*
-*
*
(Truncatulina) lobatula
*
*
*
*
— ( ) refulgens
*
*
(Anomalina) coronata
*
Pulvinulina repanda type
*
*
■ Auricula
*
*
Karsteni
*
concentrica
*
elegans
*
*
*
Menardii subtype
*
*
*
**
**
*
Canariensis
*
*
**
**
pauperata \ .
*
*
• Micbeliniana
-*
**
*
Rotalia Beccarii type
*
*
*
nitida
1 *
*
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 433
Table IX. (continued).
1
T3
Pi
Sh'5''
g
g-3 a
2
,n o
.S l OQ
•d i-4
'o O (A
JJ^. J
^ Mo
5 [Coral-zone]
T the Irish coast. M
)eep Water of the
(200-400 fms.;. ^
Abyssal Depths
76 fms.).
Abyssal Depths
ns.), “ Boreal os
ice.”
7
rt s
S
■|-i
fi
rrovmce
1 (after Bailey). ^
Genera, Species, and Varieties.
Fathoms ...
§ 8
•3 O C3
JJjr
.-T^ 3
% o v —
-8 O
3
l Coral-zone [50-10
| Isles ; represent!
land Fauna (Mr. H
l of 60-8
North Atlantic
i (43-90 fms.); oi
f
! North Atlantic ; I
, Eastern Plateau
A.
f
! North Atlantic ;
, (1750-21'
f North Atlantic;
(1450-2350 ft
Provii
<D ^
O m
■B o
a ^
£<4
o r— f
o CO
gcg
ia
°
O 1
O Oi
i — i-t
0-80.
43-90.
20(4400.
1750-2176.
1450-2350.
10420.
49-105.
1450-2350.
A
Rotalia Soldanii
F
*
*
r~
*
A
*
orbicularis
*
*
*
Tiiioporus lsevis * . . .
*
*
Patellina corrugata
*
*
Nummulina radiata •
*
(Operculina) ammonoides
*
**
**
Polvstomella crispa type
*
striatopunctata
*
*
*
*
Arctica
*
(Nonionina) umbilicatula
*
*
**
*
*
( ) depressula
*
( ) turgida
*
*
*
*
( ) Scapha
*
*
• ( ) stelligera
*
( ) asterizans subtype
*
*
Valvulina Austriaca
*
*
Lituola nautiloidea type
*
Canariensis
*
*
*
Scorpiurus
*?
*
Trocbammina inflata
*
*
incerta
*
*
Cornuspira foliacea type
*
*
Hiliola (Quinqueloculina) Seminulum . . type
**•
**
*-*
*
*
*
*
( ) agglutinans
*
( ) secans
*
*
( ) bicornis
*
( ) Ferussaeii
*
( ) pulcbella
*
( ) subrotunda
*
( ) tenuis
*
*
(Triloculina) oblonga . . .
*
*
*
( ) Brongniartii
-*
*
( ) trigonula subtype
*
*
( ) tricarinata
*
(Biloculina) ringens subtype
*
*
( ) compressa
*
*
( ) depressa
*
*
*
— » ( ) elongata
*
*
*
*
( ) Sphaera
*
*
( ) contraria
*
(Spiroloculina) planulata subtype
*
*
*
*
*
( ) limbata
*
*
*
• ( ) excavata
*
( ) canalieulata
*-
*
*
434
ME. W. K. PAEKEE. AND PEQEESSOE T. E. JONES ON SOME
Appendix YI. — General Distribution of Foraminifera.
For the comparison of the Arctic and North-Atlantic Foraminifera with those of other
seas, we selected twenty-nine sets of specimens from different parts of the Atlantic, Medi-
terranean, Red Sea, Indian Ocean, and Pacific, and showed in Table VII. the relative
distribution of such of them as we have obtained from the Arctic and North-Atlantic
sea-beds. Most of the localities, however, yielded other forms, the enumeration of
which will complete what we know of the Foraminiferal fauna of each of the places
quoted in Table VII. ; and, as the proportional size and occurrence can also be indi-
cated, so many complete lists will furnish material help in the study of representative
; groups of; Foraminifera, as to their distribution and habits.
Table X. — Showing the Foraminifera belonging to the several Dredgings and Soundings
indicated in Table YII., but omitted there as not being known in the Arctic and North-
Atlantic Sea-beds. (The materials of this Table and of Table VII., taken together,
supply perfect lists of the Foraminiferal Fauna for the several localities. Columns
Nos. 5, 11, 12, 13, & 25 of Table YII. are complete in themselves.)
kvl. Yery large. 1. Large. rl. Bather large. to. Middle-sized. s. Small. vs. Yery small.
YC. Yery common. C. Common. EC. Eather common. EE. Eather rare.
E. Eare. YE. Yery rare.
: Additional Geneea, Species, and
Yaeieties.
Additional Geneea, Species, and
Yaeieties.
Eoe Column No. 1.
Foe Column No.- 6.
Trochammina inflata, Montag
vl YC
j Polystomella strigillata {3~ P &
rs EE
Bulimina pupoides, D’O
TO E
Textularia variabilis, Will
s E
Foe Column! No. 2.
Trochammina inflata, Montag
to YC
Uvigerina aculcata D,0
-as E
Triloculina Brongniartii, D’O.
TO. C
Textularia variabilis, Will
vs YC
Yerneuilina pygmsea, Egger
: VS C
Trochammina inflata, Montag
vl YC
' Foe Column No. 7.
Lituola agglutinans, D’O
Polystomella strigillata, /3, F. & M
TO C
Tinoporus laevis, P. & j
s E
Foe Column! No. 3.
Spiroloeulina exeavata, D’O
TO C
Quinqueloculina secans, D’O
rl C
Nodosaria aculeata, D’O.
vs "V'lt
• pulchella, D’O
rl C
Textularia variabilis, Will.
s C
Triloculina trigonula, Lam
TO C
Brongniartii, D’O
rl C
Foe Column No. 4.
Foe Column No. 8.
Nonionina granosa, D’O
psC
Bulimina pupoides, D’O
rs C
Quinqueloculina1 secans D’O
l YC
Textularia variabilis, Will
s C
FORAAIINIFEEA FR031 THE NORTH ATLANTIC AND ARCTIC OCEANS. 435
Table X. (continued).
Additional Genera, Species, and
Varieties.
Additional Genera, Species, and
Varieties.
For Column No. >9.
Polystomella strigillata, (3, F. & 31.
Bulimina pupoides, D’O
Textularia variabilis, Will
Quinqueloculina secans, D’O
For Column No. 10.
Polystomella strigillata, (3, F. & M.
Bulimina pupoides, D’O
Trochammina inflata, Montag. . . .
Quinqueloculina secans, D’O
pulchella, D’O
Triloculina Brongniartii, D’O.
For Column No. 14.
Lingulina carinata, D’O
Dentalina brevis, D’O
elegans, D’O
Acicula, Lam
Yaginulina Badenensis, D’O
Eimulina glabra, D’O.
Marginulina tuberosa, D’O
Falx, P. & J
elongata, D’O
Cristellaria Calcar, Linn
Italica, Defr
Yortex, F. & M
Uvigerina aculeata, D’O
Globigerina hirsuta, D’O
helicina, D’O
Planulina Ariminensis, D’O
Planorbulina reticulata, Czjzek . . .
Pulvinulina repanda, F. & 31.
Cassidulina oblonga, Ess
Bolivina Triticum, nov
Textularia carinata, D’O
conica, D’O
Bigenerina rugosa, D’O
Y erneuilina triquetra, Miinst
Clavulina communis, D’O
Webbina* clavata, P. & J
Trochammina incerta, D’O
charoides, P. & J
Spiroloculina abortiva, nov.
canaliculata, D’O
Biloculina Sphaera, D’O
Lituola Cenomana, D’O
vs C
vs EC
s EC
Z EE
to C
to EE
m C
to EC
TO C
TO C
Z c
TO C
zc
TO C
TO C
rl EC
TO C
TO C
TO C
rl C
TO EC
TO EC
TO C
TO E
TO EC
TO YC
toC
Z C
TO EE
TO EE
to EC
to EC
vl C
to EC
Z YC
Z YC
to EC
TO EC
s E
TO C
TO C
vs E
For Column No. 15.
Eotalia ornata, D'O
Calcarina rarispina, Desh. . . . .
Defrancii, D’O
Cymbalopora Poeyi, D’O
Pulvinulina Schreibersii, D’O.
Auricula, F. & 31
Cassidulina serrata, Ess
Polystomella discoidalis, D’O. . . .
Ampbistegina vulgaris, D’O. . . .
Bolivina plicata, D’O
Yerneuilina spinulosa, Ess ,
Textularia Partschii, Czjzek . . ,
pectinata, Ess
Trockus, D’O
Candeiana, D’O,
Spiroloculina alata, nov
Quinqueloculina Sagra, D’O. . .
pulchella, D’O
Biloculina Sphsera, D’O.
For Column No. 16,
Dentalina elegantissima, D’O. . . ,
■Uvigerina aculeata, D’O
Sagrina dimorpha, P. & J
Globigerina helicina, D’O
Eotalia ornata, D’O
Cymbalopora Poyei, D’O
Planorbulina ammonoides, Ess. .
Pulvinulina pulchella, D’O
Auricula, F. & M
excavata, D’O
Schreibersii, D’O
Amphistegina vulgaris, D’O. . . .
Cassidulina oblonga, Ess
Bolivina dilatata, Ess
plicata, D’O
- — — Triticum, nov
Textularia Candeiana, D’O
praelonga, Ess. . .
pectinata, Ess
Yertebralina inaequalis, Gm. . . .
alata, nov
Spiroloculina alata, nov
Orbitolites complanatus, Lam. .
to C
s C
s C
toC
TO C
TO C
TO E
TO C
TO 0
toC
to EC
toC
to EC
m EC
TO EC
ZC
Z E
TO C
sE
s E
* C
sE
TO C
s E
TO C
sEC
TO C
toC
rs EC
to EE
vs EC
vs EC
■TO C
TO C
s E
TO C
sEC
to EC
vs C
vs C
sEE
vs EE
* We retain D’Orbigny’s term Webbina for the subtype
with its varieties W. clavata, &c:
of Trochammina which he named Webhina irregularis,
436
ME. W. K. PAEKER AND PEOPESSOE T. E. JOKES ON SOME
Table X. (continued.)
Additional Genera, Species, and
Varieties.
Additional Genera, Species, and
Varieties.
Polystomella Sagra, D’O
m VC
Por Column No. 17.
discoidalis, D’O
TO VC
Bolivina Triticum, nov
to EC
s C
Verneuilina spinulosa, Ess
TO C
l VC
Textularia Candeiana, D’O
TO C
Z VC
Spiroloculina canaliculata, D’O.
TO EC
Quinqueloculina Sagra, D’O
8 EC
s E
pulchella. D’O
8 EC
s C
Triloculina trigonula, Lam
to EC
dilatata, Ess
s EE
Textularia variabilis, Will
m EC
Candeiana, D’O
to EE
Por Column No. 21.
praelonga, Ess
mEC
Marginulina tuberosa, D’O.
s E
Uvigerina aculeata, D’O
Z C
Globigerina helicina, D’O.
Z VC
Por Column No. 18.
Anomalina variolaria, D’O.
rl E
Planorbulina Culter, P. & J
to EC
s C
Clemen tiana, D’O
rl E
Z VC
Pulvinulina crassa, D’O.
Z VC
l VC
cuneiformis, nov
Z VC
Sphaeroidina dehiseens, P. & .T
vl VC
Bolivina dilatata. Ess
s EE
Pullenia obliquiloculata, P. & J
vl VC
Textularia Candeiana, D’O
to E
Cassidulina oblonga, Ess
vl C
Trochammina charoides, P. & J
s E
serrata, Ess
Z C
Spiroloculina alata, nov
TO C
Verneuilina spinulosa, Ess
rl E
Peneroplis pertusus, Porsk
s E
Textularia variabilis. Will
s C
Por Column No. 19.
Por Column No. 22.
Uvigerina aculeata, D’O
s EC
Planulina Ariminensis, D’O
TO C
Sagrina Eapbanus, P. & J
to EC
Pulvinulina pulchella. D’O
TO C
Eotalia dentata, P. & J
TO VC
Sehreibersii, D’O
rl C
ornata, D’O
TO VC
Verneuilina spinulosa, Ess
to EC
Planorbulina ammonoides, Ess
s EE
■ Lituola Soldanii, P. & J
Z C
Pulvinulina Auricula, P. & M. . .
s C
■ pulchella, D’O
TO C
Polystomella Sagra, D’O
to EC
Por Column No. 23.
Bulimina pupoides, D’O
s VC
Bolivina hyalina, nov
s VC
Nodosaria hirsuta, D’O
TO C
Verneuilina spinulosa, Ess.
s E
Uvigerina aculeata, D’O
TO C
Textularia variabilis, Will
s EE
Sagrina dimorpha, P. & J. . .
TO C
Quinqueloculina dilatata, D’O
s E
Planulina Ariminensis, D’O
TO C
Peneroplis pertusus, Porsk
s C
Planorbulina ammonoides, Ess
to EC
reticulata, Czjzek
z c
Pulvinulina crassa, D’O
TO C
Por Column No. 20.
Pullenia obliquiloculata, P. & J
TO EC
quinqueloba, Ess
sEC
Sagrina Eaphanus, P. & J
to EE
Bolivina plicata, D’O
TO EC
Eotalia Schroeteriana, P. & J.
Z EE
dilatata. Ess
z c
anneetens, P. & J
l c
Triticum, nov
s C
Planulina Ariminensis, D’O
s EC
Verneuilina spinulosa, Ess
s E
Planorbulina ammonoides, Ess
s EC
Gaudryina Badenensis, Ess
TO C
Cymbalopora Poeyi, D’O
to EC
Textularia praelonga, Ess
to EC
Pulvinulina Auricula, P. & M
sEC
Trochammina inflata, Montag
s EE
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 437
Table X. (continued.)
Additional Genera, Species, and
Varieties.
Additional Geneea, Species, and
Varieties.
Z RC
Calcarina Spengleri, Gm
to RR
Polystomella craticulata, F. & M
vl YC
Quinqueloculina pulchella, L’O
s RR
Amphistegina vulgaris, D’O
TO YC
Bulimina convoluta, Will
s R
Bolivina Triticum, nov
s R
dilatata, Rss
TO R
Foe Column No. 24.
Yerneuilina spinulosa, Rss
s R
Textularia Partschii, Czjzek
Z YC
s R
Trochus, D’O
Z YC
Z RC
Candeiana, D’O
Z YC
s C
praelonga, Rss
vl C
to RR
Valvulina Parisiensis, D’O
s RR
s C
angularis, D’O. . .
TO C
s C
Tinoporus vesicularis, P. & J
TO R
Spiroloculina rugoso-depressa, nov
Z C
s R
striata, D’O
to RC
to R
Quinqueloculina Sagra, D’O
Z YC
pulchella, D’O
TO VC
Inca, D’O
z c
s RR
rugoso-saxorum, nov
z c
Triloculina trigonula, Lam
s R
Hauerina plicata*, P. & J
TO C
Foe Column No. 26.
complanata, nov
TO C
Yertebralma Cassis, D’O
TO C
Globigerina hirsuta, D’O
Z C
conico- articulata, Batsch
TO C
helicina, D’O
Z C
Alveolina sabulosa, Montf.
TO C
Pulvinulina cuneiformis, nov
Z RC
Alveolina Quoyii, D’O
TO C
Sphseroidina dehiscens, P. & J
vl VC
Orbitolites complanatus, Lam
TO YC
Pullenia obliauiloculata, P. & J. . . .
vl VC
Peneroplis pertusus, Forsk
Z YC
Dendritina Arbuscula, D’O
Z YC
Spirolina Lituus, Gm
s RR
Foe Column No. 27.
Dactylopora Eruca, P. & J
TO R
Dentalina Acicula, Lam
ZR
Yaginulina Badenensis, D’O
s R
Foe Column No. 29.
Uvigerina aculeata, D’O
to RR
Globigerina hirsuta, D’O.
to C
Discorbina vesicularis, Lam. . .
to RC
Planorbulina farcta, F. & M.
TO C
Turbo, D’O.
rl C
Pulvinulina crassa, D’O
to YC
Polystomella craticulata, F. & M
TO C
Cassidulina oblonga. Rss
TO C
Bolivina plicata, D’O ;
m RR
Bolivina dilatata, Rss
TO C
Textularia Candeiana, D’O
TO C
• Yerneuilina pygmsea, Egger
TO R
Valvulina Polystoma f, P. & J
TO C
Gandrvina Badenensis, Rss
s R
Parisiensis, D’O
TO C
Textularia variabilis, Will. . . .
to RC
angulosa, D’O.
TO C
Spiroloculina striata, D’O
zc
Quinqueloculina tricarinata, D’O
vl RC
Foe Column No. 28.
Sagra, D’O
Z RC
Triloculina trigonula, Lam
s C
Lagena squamoso-marginata, P. &r. ,T. . .
TO C
Vertebralina Cassis, D’O.
rl C
Rotalia ornata, D’O
z c
striata, D’O
Z YC
Planorbulina vulgaris, D’O
to RC
insequalis, Gm
TO R
Pulvinulina pulchella, D’O
Orbitolites complanatus, Lam
TO VC
Auricula, F. & M
TO C
Ponoroplis pprttisns, "FVvrsk
to YC
Cymbalopora Poeyi, D’O
s RC
Spirolina Lituus, Gm
to RC
squamosa, D’O
Z R
Nubecularia lucifuga, Defr
to RC
1
* Carpenter’s Introd. Foram. pi. 6. fig. 35.
MDCCCLXV. 3 N
Ibid. pi. 11. figs. 21 & 24.
438
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Table X. (continued.)
Additional Genera, Species, and
Varieties.
Additional Genera, Species, and
Varieties.
Z c
For Column No. 31.
Polymorphina Thouini, D’O
to C
rs VR
Uvigerina aculeata, D’O
vs R
« E
Polystomella discoidalis, D’O
to C
to C
Bulimina pupoides, D’O
TO C
to RC
Bolivina plicata, D’O
TO C
vl VC
hyalina, nov. . .
TO R
s RR
Textularia variabilis, Will
s RC
vl VC
vl VC
sC
For Column No. 32.
vl VC
to R
Calcarina Spengleri, Gm
TO C
l C
Defrancii, D’O
s RR
s RC
Rotalia annectens, P. & J
TO C
l RC
s RC
craticulata, P. &l J. . . .
TO C
Planorbulina farcta, F. & M
to RC
l C
Cymbalopora Poeyi, D’O
TO C
ZC
Discorbina Turbo, D’O
TO C
ZVC
ZC
■ .. Pileolus, D’O
to RC
Polystomella craticulata, F. & M
TO C
to VC
■ — macella, F. & M
Heterostegina depressa. D’O
TO C
to C
TO C
sR
Amphistegina vulgaris, D’O
TO C
ZVC
Textularia conica, D’O
toRC
vl RC
Tinoporus laevis, P. & J
ZC
Z C
sphserulo-lineatus t, P. & J
ZC
to C
Polytrema miniaceum, Esper
Z RC
ZVC
Spiroloculina striata, D’O
to RC
ZVC
Quinqueloculina tricarinata, D’O
ZC
ZC
Triloculina reticulata J, D’O
Z RC
Z RC
Peneroplis pertusus, Forsk
TO VC
to RC
Orbitolites complanatus, Lam
vl VC
Alveolina Quoyii, D’O
vl VC
Eos Column No. 30.
Lagena distoma-xnargaritifera, P. & J
Dentalina brevis, D’O
Vagiiralina Badenensis, D’O
Polymorphina Thouini, D’O. .......
elegantissima, nov
Planorbulina vulgaris, D’O
— — — ammonoides, Ess
Discorbina vesicularis, Lam
dimidiata, P. & J
biconcava, P. & J
Turbo, D’O
Cora, D’O
Polystomella macella, E. & M
strigillata (3, E. & M
Textularia variabilis, Will
Folium, P. & J
Valvulina Parisiensis, D’O.
angularis, D’O
mixta*, P. & J
Polystoma, P. & J
triangularis, D’O
Patellina annularis, P. & J
simplex, P. & J
Spiroculina striata, D’O
Quinqueloculina tricarinata, D’O. . . .
pulcbella, D’O
secans, D’O
dilatata, D’O
Triloculina striato-trigonula, nov. . . .
Vertebralina striata, D’O
Peneroplis pertusus, Forsk
Spirolina Lituus, Gm
In these Tables (VII. & X.) we have materials for a conspectus of nearly all the
Foraminiferal Genera (of which few, if any, can be said to have more than one true
species), as represented by one form or another, type or subtype, species or variety, in
widely distant parts of the world, under very different conditions of climate, depth, and
sea-bottom.
It is probable that, in some of the instances tabulated, the smallness of the quantity
of sand, clay, or ooze manipulated has limited the catalogue of forms, and therefore
that further observation is necessary ; nevertheless, the freedom with which some genera
range over the globe, whilst others are limited to narrow areas, or rather to special con-
ditions, is readily apparent. Table XI. exemplifies this.
* Carpenter’s Introd. Eoram. pi. 11. figs. 19, 20, 25, 26.
f Ibid. pi. 15. fig. 1. i Ibid. pi. 6. fig. 13.
■% [Phil. Trans. 1865. To face page 438.
Table XI. Showing the distribution of the Genera of Foraminifera in Thirty-two Gatherings from the Atlantic, Mediterranean, Red Sea, Indian Ocean, and Pacific.
i
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Genera of
F ORAM INIFERA
(represented by-
species or varieties).
Sub-recent. Peterborough Fen, 1 mile from its western
boundary (sandy clay).
Sub-recent. Peterborough Fen, 2 miles from its western
boundary (sandy clay).
Sub-recent (clay). Boston, Lincolnshire.
Sub-recent (clay). Wisbech, Cambridgeshire
(Valley of the Nene).
Mouth of Thames, Southend (shallow-water sands).
Pegwell Bay, near Margate, Kent (muddy shore-sand).
Isle of Arran, N.B. (muddy sands from shallow water).
Douglas, Isle of Man (shallow-water sands).
Eastbourne, Sussex (mud from shallow water) .
Colne (tidal) River, Essex (oyster-beds).
Greenland (Arctic). See Table IV.
Norway (Arctic). See Table IV.
North Atlantic, Ireland to Newfoundland, thirty-nine
casts, from 43 to 2350 fms. See Table V.
Mediterranean. Galita Island, S. 32° W., 32 miles.
Lat. 38° 00' N., Long. 9° 13' E., 320 fms.
Red Sea. Gulf of Suez (muddy, shelly sand). 30 fms.
Lat. 28° 38' N., Long. 33° 9' E.
Red Sea, close to Island Shadwan, off S.E. point,
entrance of Jubal Strait, 372 fms. (light-yellow clay).
Red Sea, 557 fms. Lat. 17° 49' N., Long. 40° 2' E.
(various-coloured mud).
Red Sea, 678 fins. Lat. 23° 30' N., Long. 36° 58' E.
(pale clay).
Black Anchor-mud, Bombay Harbour.
Dark Anchor-mud, Hong Kong, 8 or 9 fms.
Tropical Atlantic, 1080 fms. Lat. 2° 20' N.,
Long. 28° 44' W. (almost entirely organic).
South Atlantic, Abrolhos Bank, 47 fms.
Lat. 23° 02' S., Long. 41° 02' W. (sand).
South Atlantic. Abrolhos Bank, 260 fms.
Lat. 22° 54' S., Long. 40° 37', W. (dark mud).
South Atlantic, Abrolhos Bank, 940 fms.
Lat. 19° 32' S., Long. 37° 51|' W. (whitish mud).
South Atlantic, 2700 fins. Lat. 26° 45' S.
Long. 32° 52' W. (pale mud).
Indian Ocean, 2200 fins. Lat. 5° 37' S., Long. 61° 33' E.
(fine white calcareous mud, with Polycystineae).
Indian Ocean, two casts near each other, 900 and
1120 fins. Lat. 36° 58', Long. 51° 49' E. (pale mud.)
Australia, Coral-reef) 17 fms. (white shelly mud).
| Swan River, Australia, 7 or 8 fms. (white shelly mud).
Melbourne, Australia, Coast-sand (coarse quartz sand,
full of shells, zoophytes, sponges, and algae).
Black Anchor-mud, Hobson’s Bay, Australia.
Fiji, coral-reef, and adherent to a hydroid polype.
*
*
*
*
*
*
:
'
*
*
‘
*
*
*
*
*
*
*
*
’
*
Orbulina
*
Spirillina
*
*
t
*
*
*
(ilobigerina
*
*
Pallenia
*
*
*
*
*
Sphocroidina
*
Textularia
*
*
*
Bulimina
*
*
*
*
*
*
*
Cassidulina
*
*
*
*
*
*
*
*
Discorbina
* ’
*
*
*
*
*
*
Planorbulina
' '
*
*
*
*
*
*
*
*
Pulvinulina
*
*
*
*
*
*
*
*
*
&
*
*
'
llotalia
*
.
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
Cymbalopora
*
*
*
*
*
*
*
*
*
*
*
*
Calcarina
*
*
*
*
Tinoporus
*
*
Patellina
*
*
*
*
*
Polytrcma
Amphistegina
*
Nummulina
*
*
*
Polystomella
*
' '
*
*
*
*
*
*
*
*
Heterostegina
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
Yalvulina
Lituola
*
*
*
*
*
*
*
* 1
Trochammina
*
*
*
*
*
*
*
*
*
*
*
*
*
*
Comuspira
*
*
*
*
*
*
1
Nubecularia
*
*
*
*
*
*
*
*
*
Yertebralina
*
*
Miliola
*
*
*
*
*
*
Peneroplis
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
Alveolina
*
*
*
*
*
*
Orbitolites
*
*
Dactylopora
*
*
*
*
*
1
2
3
4
5
6
7
' 8
9
10
11
12
13
14
15
16
17
18
19
20
1 21
22
23
24
25
26
| 27
28
29
30
31
32
FORAMINIFERA FROM THE NORTH ATLANTIC AND ARCTIC OCEANS. 439
Appendix VII. — The North- Atlantic Soundings.
Owing to our having taken the positions of the soundings from the MS. labels, we
find in some instances discrepancies as to the depths and positions given in the pub-
lished Report, arising probably from corrections of the observations in some cases, and
from errors of copying and printing in others. Some, also, of our specimens are not
noted in the Report, as, for instance, Nos. 15, 25, 31, 34, 35, & 36 ; and Nos. 4 & 33
can be only doubtfully recognized. No. 21 (80) has 1405 instead of 1450 fathoms;
No. 26 (22) has 2250 instead of 1660 fathoms ; and No. 28 (86) has 2050 instead of
1950 fathoms; and there are minor discrepancies of depth and position, as the annexed
Table indicates. These we point out now, to save any waste of labour to those who
wish to verify our work.
In consequence of the differences in some of the manuscript and printed positions, the
vertical lines drawn over the reduced copy of Commander Dayman’s Chart (Plate XII.)
are often merely approximative ; and the Section of the Sea-bed is not quite correct at
Soundings No. 21 (80) & 26 (22).
Table XII. — The Thirty-nine Soundings described in the foregoing Memoir ; with their
positions and depths, as indicated by the MS. Labels and by the printed Report.
Nos. in
Table V.
From the Labels.
A-
From the Admiralty Report.
Remarks.
Nos.*
Fms.
Lat. N. & Long. W.
Nos.*
Fms.
Lat. N. & Long. W.
Materials t.
Page.
1
53
195
Lt.
48
6
30
195
Lt.
48
0
30
Mud.
56
Ln.
53
27
35
Ln.
53
27
45
2
49
129
Lt.
48
0
10
129
Lt.
48
8
10
Stones, mud.
56
Ln.
53
26
36
Ln.
53
22
36
3
47
190
Lt.
48
9
0
190
Lt.
48
9
5
Mud.
56
Ln.
53
15
0
Ln.
53
15
0
4
39
124
Lt.
48
15
30
9
125
Lt.
48
15
15
Blue mud.
56
Possibly the same Soundings, j
Ln.
53
13
0
Ln.
53
9
0
5
45
150
Lt.
48
9
45
150
Lt.
48
9
54
Blue mud.
56
Ln.
53
10
50
Ln.
53
10
50
6
41
129
Lt.
48
11
0
129
Lt.
48
12
0
Mud.
56
Ln.
53
7
50
Ln.
53
7
55
7
61
167
Lt.
48
14
22
167
Lt.
48
14
22
Dark mud.
56
Ln.
53
1
0
Ln.
53
1
0
8
59
133
Lt.
48
18
0
133
Lt.
48
17
55
Dark mud.
56
Ln.
52
56
0
Ln.
52
45
50
9
55
112
Lt.
48
21
0
112
Lt.
48
21
0
Mud, stones.
56
Ln.
52
44
0
Ln.
52
42
40
10
65
102
Lt.
48
28
30
102
Lt.
48
28
30
Stone, clay.
56
Ln.
52
19
30
Ln.
52
19
30
11
69
146
Lt.
48
40
0
146
Lt.
48
40
0
Mud, stone.
56
Ln.
51
45
0
Ln.
51
45
0
12
63
145
Lt.
47
57
20
145
Lt.
47
57
20
Mud.
56
Ln.
51
31
30
Ln.
53
31
30
13
73
161
Lt.
49
0
0
161
Lt.
49
0
0
Mud.
56
Ln.
50
48
30
Ln.
50
48
30
* These numbers refer to the compartments of the box containing the specimens. + See also Table YI.
440
ME. W. K. PAEKEE AND PEOEESSOE T. E. JONES ON SOME
Table XII. (continued).
.s
From the Labels.
From the Admiralty Beport.
.a. _ . .
Behakks.
.0 3
!fos.*
Fms.
Lafc. N. & Long. W.
Nos.*
Fms.
Lat. N. & Long. W.
Materials t.
Page.
14
33
405
Lt.
49
2
0
405
Lt.
49
5
0
Mud.
55 & 59
Ln.
50
14 30
Ln.
53
3
0
15
77
221
Lt.
49
23 30
Ln.
49
55
0
16
78
329
Lt.
49
26
0
330
Lt.
49
25
0
Sand, mud.
55 & 59
331 fathoms, at p. 59.
Ln.
49
48
0
Ln.
49
48
0
17
32
740
Lt.
49
16 30
32
742
Lt.
49
12
0
Mud.
54&59
Ln.
49
17
0
Ln.
49
35
0
18
79
725
Lt.
49
18
0
79
725
Lt.
49
18
0
Mud, with a Worm.
53&59
Ln.
49
12
0
Ln.
49
12
0
19
31
954
Lt.
49
23
0
954
Lt.
49
24
0
Ooze %.
59
Our specimen of this Sound was
Ln.
48
48
0
Ln.
48
48
0
a sandy mud. See Table YI.
20
30
1203
Lt.
49
33
0
30
1203
Lt.
49
32
0
Blue mud, with “remains
51&59
Lat. 49° 32' 30", at p. 59.
Ln.
48
5
'0
Ln.
48
4
0
of Bones, &c.”
21
80
1450
Lt.
50
6
0
80
1405
Lt.
50
6
0
Ooze, “ full of Foraminifera,
47 &59
Lat. 50° 6' 30", at p. 59.
Ln.
45
45
0
Ln.
45
45
0
when seen in the Microscope.”
22
26
2330
Lt.
50
25
0
26
2330
Lt.
50
25
0
Ooze.
44 & 59
Ln.
44
19
0
Ln.
44
19
0
23
25
2250
Lt.
50
46
0
25
2050
Lt.
50
49
0
Ooze, with Foraminifera.
42&59
Ln.
42
20
0
Ln.
42
26
0
24
19
2035
Lt.
52
11
0
19
2030
Lt.
52
11
0
Ooze.
29 & 58
2030 fms. is the corrected depth.
Ln.
31
29
0
Ln.
31
27
0
Long. 31° 27' 30", at p. 58.
25
81
2350
Lt.
51
29
o
Compare No. 26 (22).
Ln.
38
1
0
26
22
1660
Lt.
51
30
0
22
2250
Lt.
51
29
0
Ooze.
37&58
Compare No. 25, 2350 fathoms.
Ln.
38
0
0
Ln.
38
0
0
27
85
2176
Lt.
52
16
30
85
2176
Lt.
52
16
30
Ooze.
27 &58
Long. 29° 28' 30", at p. 58.
Ln.
29
28
30
Ln. 29
28
0
28
86
1950
Lt.
52
25
0
86
2050
Lt.
52
26
0
Ooze.
26 &58
Ln.
28
10
0
Ln.
28
10
0
29
15
1776
Lt.
52
33 30
15
1800?
Lt.
52
46
0
Ooze, with Foraminifera
21&58
Ln.
21
16
0
Ln.
21
20
0
and Diatomaceae.
80
90
2050
Lt.
52
16
0
90
2050
Lt.
52
16
30
Ooze.
16&58
Ln.
16 46
0
Ln.
16 46
0
31
13
2050
Lt.
52
16
0
Compare No. 30 (90), 2050 fms.
Ln.
16'
42
0
32
12
1750
Lt.
52
21
30
l:
1750
Lt.
52 21
30
Ooze.
14&58
Lat. 52° 21' 40", at p. 58.
Ln.
15
6
0
Ln.
15
6
0
33
93
200
Lt.
52
16
0
9
240
Lt.
52
17
0
Fine sand.
13&58
Possibly the same Soundings.
Ln.
14 30
0
Ln.
14 30
0
34
95
223
Lt.
52
11
0
35
98
415
Ln.
Lt.
13 45 0
52 8 30
1
(Not noticed, but intermediate
\ to others mentioned at pp.
( 13 & 58.
36
7
338
Ln.
Lt.
12 31
52 0
0
30
|
Ln.
12
7 30
J
1
37
99
90
Lt.
52
1
0
90
Lt.
52
1
0
Sand.
13&58
Long. 11° 14' 40", at p. 58.
Ln.
11
14
40
Ln.
11
15
0
38
100
78
Lt.
51
59
0
78
Lt.
51
59
0
Fine sand.
13&58
Ln.
11
0
0
Ln.
11
0
0
39
102
43
Lt.
51
57
0
43
Lt.
51
57
0
Fine sand.
13&58
Ln.
10 30
30
Ln.
10 30
0
* These numbers refer to the compartments of the box containing the specimens,
j Described as “ a light- coloured fine mud;” “ a soft mealy substance “ sticky;”
t See also Table YI.
FOEAMINIFEEA FEOM THE NOETH ATLANTIC AND AECTIC OCEANS. 441
In one of the above-mentioned Soundings from the Abyssal ooze-floor of the North-
Atlantic (Nos. 19-32), Commander Dayman observed “remains of bones” (No. 20);
and other rare extraneous objects were noticed by him in some of the deep soundings
not included in the foregoing Table. As the presence of Molluscan Shells and of stones
at such depths, and so far from land, are of great interest, we append an abstract of such
occurrences.
Nos*
Fins.
Lat.N.&Lon.W.
Materials.
Report, page.
Remarks.
|
103
1950
Lat. 52
37
One small stone.
17 & 58
Long. 17
39
88
2100
Lat. 52
30
Ooze, full of Foramini-
19 & 58
1
Long. 19
10
fera and Diatom acese.
b-
00
2400
Lat. 52
29
Ooze.
25 & 58
The deepest sounding showing bottom:
Long. 26
14
hut a deeper (2424 fms.) was exactly-
measured Lat. 51°9'N., Long. 40° 3' W.
18
1675
Lat. 52
14
Broken Shells.
9, 28, 58
1765 fathoms, at p. 9.
Long. 30
45
1600
Lat. 51
52
Two small stones.
9, 31, 32, 58
Marked “ oz.” on the Chart by mistake.
Long. 33
21
27
2225
Lat. 50
14
Ooze and stones.
46 & 59
Long. 45
23
28
1450
Lat. 50
9
Ooze and stones.
49 & 59
Long. 46
15
29
1495
Lat. 49
Long. 46
47
52
All stones, at p. 50.
50 & 59
Lat. 49 47 30 1 , ~ , Kn
Long. 41 51 ojmd0oze>atP-69-
* In the box of specimens.
3 o
MDCCCLXV.
Phd.TrccrLt.W)<XCIfflPlM±zJIL.
Deep-Sea-Soundings, in the north Atlantic, from Ireland to Newfoundland,
By T,ieuT J.Dayrrian, RjIT assisted byM!~ J.Scctt/, MastT R.N. H. M S. Cyclops, 1857.
/
Fbl.Trans. MD C C CLXV. PI. -XIII
G-.West.8el.
ARCTIC ' FORAMINIFERA.
FhxLTraTis. MD C C CLXV. ELJOV.
ARCTIC FORAMINIFERA.
FHb.Tnms!gDC,CCLX¥.IhtzXV.
W.West Tryrp
2Vb' ,
<£D
22a
/d* /rfb
r
39^
G- West del
70
ARCTIC FORAMINIFERA.
/
G.’West del
Phil Trains. MDCCCLXV Pl.XVI
north-atlantic foraminifera.
ThUJrans. MD CC CLXY PI XVII,
G-.West del.
N ORTH-AT LAN TIC F 0 RAMINIF E R A.
Phil. Trans. MDCCCLIV. PI .XVIII
FORAMINIFERA
WWestimp.
FORAMINIFERA.
[ 443 ]
VII. New Observations upon the Minute Anatomy of the Papillae of the Frog's Tongue.
By Lionel S. Beale, M.B., F.B.S. , Fellow of the Royal College of Physicians ,
Professor of Physiology and of General and Morbid Anatomy in King's College ,
London ; Physician to King's College Hospital , &c.
Received June 16, — Read June 16, 1864.
In this paper I propose to give the results of some recent investigations upon the minute
anatomy of the beautiful fungiform papillae of the tongue of the little green tree-frog
(Hyla arbored). The specimens have been prepared according to the principles laid
down in former communications. The success I have met with in this and other minute
anatomical inquiries is, I believe, almost entirely due to the process of investigation
which I have adopted for some years past, and which enables me to render specimens
very transparent, and to demonstrate all the tissues in one specimen. By this plan
sections are obtained so exceedingly thin, without the destruction even of the most
delicate tissues, that they may be examined under the highest powers which it is possible
to obtain (-^g- magnifying 1700 linear, and magnifying about 3000 linear).
The following are among the most recent contributions to the anatomy of the papillae
of the frog’s tongue : —
Waller: “Minute structure of the Papillae and Nerves of the Tongue of the Frog
and Toad,” Philosophical Transactions, 1847.
Billroth : “ Ueber die Epithelzellen der frosch-zunge, sowie iiber den Bau der
cylinder-und flimmerepithelien und ihr Verhaltniss zum bindegewebe,” Archiv fur
Anat. Physiologie, 1858, S. 163.
Hoyer : “ Mikroskopiche Untersuchungen iiber die zunge des Frosches,” Archiv fur
Anat. Phys. 1859, S. 488.
Axel Key: “Ueber d. Endigungen d. Geschmacksnerven in der zunge Frosches,”
Muller’s Archiv, 1861, S. 329.
Hartmann : “ Ueber die Endigungsweise der nerven in den Papillae-fungiformes der
Froschzunge,” Archiv fur Anat. Phys. 1863, S. 634.
Although the views of Axel Key are supported by schematic figures which do not
accurately represent the real arrangement of the tissues, they approach much nearer
to the truth than those of other observers. He describes two kinds of cells at the
summit of the papilla, epithelial and special cells concerned in taste. I have not
been able to verify his statements in this particular. He has not demonstrated the
peculiar network at the summit of the papilla which is seen so distinctly in my speci-
mens, and his delineations of the prolongation of the axis-cylinder alone, and its divi-
mdccclxv. 3 p
444
PROFESSOR BEALE’S NEW OBSERVATIONS UPON THE
sion into fibres far too fine to be visible by the magnifying powers employed, and the
abrupt cessation of the white substance delineated by him, are evidently schematic, —
indeed he does not pretend that the figures referred to are copies from nature. Still
his inferences regarding the division of the nerve-fibres into very fine fibres which pass
into the epithelium-like tissue at the summit of the papilla, approach much nearer
to the actual arrangement than those of any other observers with which I am
acquainted.
The latest researches upon the mode of termination of the nerves are by Dr. Hart-
mann. These are concluded in the Number of Reichert and Du Bois-Reymond’s
‘Archiv’ for 1863, which has only just been received in this country (June 1864). The
drawings of the papillae accompanying this memoir, especially fig. 65, plate 18, form an
excellent illustration of how most beautiful and well-defined structures maybe rendered
quite invisible by being soaked in aqueous solution of bichromate of potash for three
days, one day in carmine solution, and then in caustic soda !
In order that I may not express myself against the mode of preparation followed by
this and many other observers in Germany in the present day more strongly than is
justified by the results obtained as shown by their own drawings, I would refer to
Hartmann’s figure. Of this drawing it is not too much to say that it represents
nothing sufficiently definite to enable any one to form an idea of the structure of the
part. The drawing, and I conclude the preparation from which it was taken, are far
behind the day; and it seems to me- most remarkable that after all the anatomical
research of the last twenty years an observer should publish such a figure as this as a
representation of natural structure. The nerve-fibres are completely altered by the
mode of investigation followed, and the finer fibres are of course destroyed or rendered
invisible. Nor can I admit that the epithelium upon the summit of the papillae repre-
sented in his fig. 64 gives a correct idea of this structure.
It may be proved conclusively by experiments that soaking delicate animal tissues in
dilute aqueous solution of bichromate of potash renders invisible and destroys structures
which can be demonstrated by other means. Inquiries conducted by the aid of such
plans of preparation retard rather than advance anatomical inquiry, for some of the
most important anatomical characters are rendered completely invisible. The very
conflicting opinions now entertained by observers in Germany upon the structure of
these papillae, render it important that they should be studied again with the advantage
of the highest powers, and the most advantageous methods of preparation which we
now possess.
In this communication I shall only attempt to describe briefly those points which I
believe to be new, and which are I conceive demonstrated in my specimens for the first
time. Most of the points described in this paper were demonstrated more than eighteen
months ago, and during this period the specimens have been repeatedly studied and
shown to other observers. The points described can still be demonstrated in the same
specimens (June 1864).
MINUTE ANATOMY OF THE PAPILLAE OF THE FEOG’S TONGUE.
445
The structures entering into the formation of the papilla are the following : —
1. The connective tissue which forms the body of the papilla.
2. The “ epithelium.”
3. The nerve-fibres in the body of the papilla, and the fibres prolonged from them
which form a plexus upon its summit.
4. Nerve-fibres ramifying in the connective tissue, upon the capillary vessels and
amongst the muscular fibres.
5. The muscular fibres.
6. The vessels.
The Connective Tissue.
The nerves, vessels, and muscular fibres are imbedded in a very transparent basis-
substance which exhibits a slightly striated or fibrous appearance when stretched,
but this structure in all the papillae of the Hyla is exceedingly delicate and trans-
parent.
The great majority of the nuclei seen in this basis or connective substance are
undoubtedly connected with the nerves, vessels, and muscular fibres, but there are a
few which seem to belong to the connective substance alone, and may therefore be
called “ connective-tissue corpuscles .” It is possible that these at an earlier period may
have been connected with nerves or muscles ; they have descended from the same nuclei
or masses of germinal matter as the nuclei taking part in the production of these
tissues.
I consider that indefinite connective tissue of this kind results principally from the
accumulation of the remains of higher structures, especially nerve-fibres, which were in
a state of functional activity at an earlier period of life. At an early period of deve-
lopment nuclei (masses of germinal matter) can alone be detected. As development
proceeds, tissue is formed by these nuclei, and increases as age advances. The large
and fully-formed fungiform papillae have twice as many nerve-fibres as smaller and
younger ones. During the development of such an organ as one of these papillae many
changes occur, and much texture is produced and removed before the papilla attains
its fully developed state. That passive substance called connective tissue which remains
and occupies the intervals between the higher tissues, which possess active and special
endowments, slowly accumulates, but undergoes condensation as the organ advances in
age. Amongst this are a few nuclei which can no longer produce anything but inde-
finite “connective tissue” of the same character. In Plate XXI. fig. 9 it would have
been impossible, had the specimen been prepared in the usual manner, to have deter-
mined if the nuclei marked a, h were nuclei of the muscle concerned in producing
muscle, or connective-tissue corpuscles concerned in the formation of connective tissue
only. This question requires restudy from a new point of view. It is quite certain that
many of the nuclei figured in all my drawings in connexion with nerves , vessels, muscles,
and other tissues, would, if the specimens had been prepared in a different manner, so
3 r 2
446
PROFESSOR BEALE’S NEW OBSERVATIONS UPON THE
that their connexions were not so very distinctly seen, have been called “ connective-
tissue corpuscles.”
The drawings accompanying my paper explain the relation which I believe the essen-
tial structures entering into the formation of the papilla bear to the indefinite con-
nective tissue in which they lie imbedded.
Epithelium.
The so-called epithelium upon the summit of the papilla of the frog’s tongue (Plate
XXI. fig. 1, a) differs from the epithelium attached to its sides ( b ), that covering the
simple papillae (c), and that on the surface of the tongue generally, in many important
characters. As is well known it is not ciliated. The cells differ from the ciliated cells
in several points. They are smaller than these. The nucleus is very large in proportion
to the entire cell. The cells are not easily separated from one another, as is the case with
the ciliated epithelium. These cells form a compact mass, the upper surface of which
is convex. This is adherent by its lower surface to the summit of the papilla, and it is
not detached without employing force. The cells do not separate one by one, as occurs
with the ordinary epithelium, but the whole collection is usually detached entire, and it
is I believe torn away.
Although some observers would assert that the two or three layers of cells repre-
sented in my drawings do not exist, but that the appearance is produced by the cells of
a single layer being pushed over one another by pressure, I am convinced that in this
mass upon the summit of the papilla of the Hyla there is more than the single layer of
cells represented by Hartmann, who is the latest observer on this point.
Hartmann’s representation ( l . c.) of this very same structure from the summit of the
papilla of the Hyla is very different from my drawings. Not only do we represent these
same cells of very different shapes, but the nucleus in my specimens is three or four
times as large in proportion to the cell as represented by him.
The general outline of the free surface is convex (a, «, a, fig. 1, Plate XXI.), and
the tissue which intervenes between the nuclei appears very transparent and projects
a little, so as to give the convex summit a honeycombed appearance (Plate XXI.
fig. 7).
The under concave surface of this hemispheroidal mass which adheres to the summit
of the papilla of the Hyla’s tongue, corresponds to the exact area over which the nerve-
fibres of the papilla are distributed, as will presently be shown. The shape of these
cell-like bodies, of which the mass is composed, and their connexion with fibres is shown
in Plate XXI. fig. 3, and in the very highly magnified specimen represented in fig. 2.
After the examination of a vast number of specimens I think these figures represent
the actual arrangement, but this point is most difficult of investigation. In the inter-
vals between what would be called, if they were capable of complete separation from one
another, the individual cells, fibres are seen. These fibres do not I think arise simply
from the pressure to which the masses have been subjected. I have represented the
MINUTE ANATOMY OE THE PAPILLAE OF THE FROG'S TONGUE.
447
arrangement as I believe it to be in Plate XXI. fig. 6, from the central part of one of
the hemispheroidal masses. I regard the entire hemispheroidal mass as resembling in
its essential structure the network I have described at the summit of the papilla, but
the masses of germinal matter are so very close together and the fibres so much interlaced
with one another, that it is most difficult to unravel the mass without destroying it.
The arrangement at the surface is seen in Plate XXI. fig. 7.
The epithelium of the tongue generally is easily removed, but many of these hemi-
spheroidal masses remain connected with the summits of the papillae to which they
belong. From what I have stated, it will I think be admitted that the constituent
parts of the mass at the summit of the papilla could not be properly called epithelial
cells, so that, with reference to the termination of the nerves in the papilla, I think
it is more correct to say that nerves may be traced to special bodies or cells which
form a hemispheroidal mass attached to the summit of the papilla, than to assert that
the separate bodies, which compose the mass in which nerves terminate, are actual
epithelial cells.
In the simple papillae (Plate XXI. fig. 1, d) of the frog’s tongue, a “nucleus” of a nerve
sometimes projects beyond the outline of the papilla and lies amongst the epithelium.
This nucleus, however, adheres to the papilla when all the epithelial cells have been
detached. It might from its position be easily mistaken for an epithelial cell, but it is
no more really related to this structure than is a ganglion-cell, or a caudate nerve-cell
of the spinal cord. The cells of the ciliated epithelium of the frog’s tongue are not in
any instance, as far as I am able to observe, connected with the nerve-fibres. It is
probable that the opposite inference, which is still held by many observers, has resulted
from the observation of such a nucleus as is represented in Plate XXI. fig. 1, d pro-
jecting beyond and adherent to the surface of the papilla. It is really continuous
with the delicate nerve-fibres ( e ) ramifying in the substance of the papilla, but it is not
an epithelial cell, and remains adherent after every particle of epithelium has been
removed.
The nervous tissue is in all cases structurally distinct from every other tissue, in every
part of its distribution. It never blends with epithelium any more than it blends with
fibrous tissue, cartilage, bone, or muscle. If nerves exert any direct influenee upon
the nutrition of any of these tissues, the influence must be exerted through some
distance. The results of anatomical research render any physiological doctrine which
maintains that nerves act through their structural continuity with other tissues unten-
able. My own observations lead me to conclude that nerves do not directly influence
the processes of nutrition, growth, or development at all. They act only indirectly, and
affect the supply of nutrient matter distributed by modifying the calibre of the vessels,
and hence regulate the supply of blood which passes to the capillaries. The nerves
I believe really exert their influence upon the contractile muscular coat of the small
arteries and veins alone, and do not act directly upon any other tissues.
448
PROFESSOR BEALE’S NEW OBSERVATIONS UPON THE
The Nerves.
With regard to the trunks of the nerves, I remark the following facts of im-
portance : —
1. That the bundle of nerve-fibres distributed to a papilla always divides into two
bundles which pursue opposite directions. The division of the bundle may take place
just at the base of the papilla, or at some distance from it, hut it always occurs (Plate
XXI. fig. 1).
2. Fine pale nerve-fibres pass from the same trunk of dark-bordered fibres as that
which gives off the bundle of nerves to the papilla. The fine fibres ramify —
a. Amongst the muscular fibres of the tongue (Plate XXI. figs. 1, 9).
h. Upon the vessels (Plate XXI. fig. 1, i, i, i).
c. In the connective tissue of the tongue generally, and also in the simple papillae
(Plate XXI. fig. 1 ,d,e).
The division of the bundle at the base of a papilla is shown in Plate XXI. fig. 1, and
in Plate XXII. fig. 10 is a diagram to indicate the manner in which the nerve-plexuses
at the summits of the papillae are connected together by commissural fibres. Thus in
action the papillae may be associated together. The bearing of this arrangement upon
the existence of complete nervous circuits is discussed in my ‘ Archives,’ vol. iv. The
bundle in the central part of the papilla consists of dark-bordered fibres, which frequently
cross and interlace with one another in this part of their course. They vary much in
diameter, some being so fine as scarcely to be visible.
As the bundle passes towards the summit of the papilla, the individual fibres divide
and subdivide into finer branches. Now, as I have before remarked, nerves so near
their distribution as these do not usually possess an axis-cylinder as a structure distinct
from the white substance. The white substance does not abruptly cease, while the axis-
cylinder is alone prolonged onwards by itself as is often described, but the entire fibre
divides and subdivides. In fact dark-bordered nerve-fibres, near their ultimate ramifica-
tions, always consist of fatty albuminous material imbedded in a transparent matrix of
connective tissue. The “tubular membrane,” “white substance,” and “axis-cylinder”
can never be demonstrated as distinct structures near the peripheral distribution of
nerves. The “ tubular membrane ” is nothing more than the transparent matrix in
which one or more nerve-fibres are imbedded.
The dark-bordered fibres divide into finer fibres about the level of the ring or half-ring
of capillaries at the summit of the papilla. As the fibres are exceedingly transparent,
they are usually lost from view about this point. For example, Hartmann’s figures
convey the idea that distinct dark-bordered fibres can be followed as high as this point,
but that they cannot be traced further. Above this spot the papilla is a little thickened
and the tissue more granular, and hence it is not to be wondered at that great difficulty
should have been experienced in demonstrating the further course of the nerves, or that
many different views should be entertained upon the oft debated question of the mode
MINUTE ANATOMY OE THE PAPILLAE OE THE FROG’S TONGUE.
449
of ending of nerves in this situation ; but it is most certain that the fibres do divide and
subdivide into finer and much more transparent fibres at this point, and that these again
divide and subdivide and form an elaborate plexus in the summit of the papilla, which
has not been before described.
By reference to the figure, the arrangement, which is not easily described with
accuracy, will be at once understood, so that a minute description of it would be super-
fluous.
Above the plexus c (Plate XXI. fig. 3), and below the epithelium-like organ at the
summit of the papilla (a), is a layer ( b ) which appears to be composed of granular matter.
In my most perfect specimens, however, this “granular layer,” when examined by very
high powers under the influence of a good light, is seen to consist of a plexus of
extremely fine fibres which interlace with one another in every direction, but which
pass from the plexus above to the epithelium-like nervous (1) organ upon the summit
of the papilla (Plate XXI. fig. 2). I believe this granular appearance to result from
the extreme delicacy and fineness of the nerve-fibres at this part of their course. In
like manner the “ granular matter” seen in the grey matter of the cerebral convolutions
and that of the retina, results mainly from the breaking down of very fine and delicate
nerve-fibres, which undergo disintegration very soon after death, unless they are sub-
jected to special methods of preparation.
Of the existence of the elaborate network of nerve-fibres with the large nuclei, repre-
sented in Plate XXI. fig. 3 c , there can be no question whatever ; but there may be
some difference of opinion regarding the exact relation of the very fine nerve-fibres at
the summit of the papilla, to the peculiar cells which surmount it, and the nature
of the granular matter just described. However, there are but two possible arrange-
ments : —
1. That the nerves form a network of exceedingly fine fibres upon the summit of the
papilla, upon which the bases of the epithelium-like cells impinge.
2. That the very fine nerve-fibres are really continuous with the peculiar and epithe-
lium-like cells ; in which case these bodies must be regarded as part of the nervous
apparatus.
There seems to me to be so much strong evidence in favour of the last view, that 1
venture to express a decided opinion that this is the truth. In many specimens I have
seen, and most distinctly, the delicate network of fibres represented in Plate XXI.
fig. 3 continuous with the fine nerve-fibres in the summit of the papilla, and I have
demonstrated the continuity of these fine fibres with the matter of which the outer part
of these peculiar cells consists (Plate XXI. figs. 2, 3, 6). I have also seen what I
consider to be nerve-fibres in the intervals between some of these cells (Plate XXI.
fig. 7). Upon the whole I am justified in the inference that there is a structural
continuity between the matter which intervenes between the masses of germinal matter
at the summit of the papilla and the nerve-fibres in its axis, and I consider that an
impression produced upon the surface of these peculiar cells may be conducted by con-
450
PROFESSOR BEALE’S NEW OBSERVATIONS UPON THE
tinuity of tissue to the bundle of nerve-fibres in the body of the papilla. These peculiar
cells in the summit of the papilla cannot therefore be regarded as epithelium, and the
mass constitutes a peculiar organ which belongs not to epithelial structures, but to the
nervous system.
Although there can be no doubt whatever as to the existence of an intricate and
exceedingly delicate nervous network or plexus at the summit of every papilla, such
a plexus might be connected with the nerves according to one of two very different
arrangements : —
1. The plexus might be formed at the extremity of a nerve or nerves, as represented
in diagram (Plate XXII. fig. 17).
2. The plexus might form a part of the course of a nerve or nerves, as represented in
diagram (Plate XXII. fig. 18).
If the first be true, the network must be terminal, and impressions must be conveyed
along the fibre, of which the plexus is but the terminal expansion, direct from peri-
phery to centre. If the second arrangement is correct, the network forms a part of a
continuous circuit or of continuous circuits. I believe the division of the nerves at the
base of the papilla, already adverted to, is alone sufficient to justify us in accepting the
second conclusion as the more probable ; but when this fact is considered with reference
to those which I have adduced in my paper published in the ‘ Transactions ’ for 1863,
and that in the ‘Proceedings’ for June 1864, and the observations published in several
papers in vols. ii., iii., and iv. of my ‘Archives,’ and in the Croonian Lecture for 1865,
I think the general view in favour of complete circuits is the only one which the anato-
mical facts render tenable. The mode of branching and division of trunks and individual
fibres is represented in Plate XXII. figs. 20, 21, 22, 23.
From the number and size of the nerve-fibres constituting the bundle in the centre of
the papilla, we should infer that the finest ramifications resulting from the subdivision
of these branches would be very numerous, since it has been shown that the fine fibres
resulting from the subdivision of a single dark-bordered fibre in the frog’s bladder,
palate, skin, and muscle, constitute plexuses or networks which pass over a very extended
area. The mode of formation of a nerve-plexus is represented in Plate XXII. figs. 11
& 14. In these beautiful little organs the numerous fibres resulting from the sub-
division of the dark-bordered fibres are distributed over a comparatively small extent
of tissue, forming the summit of the papilla. Still we have the same formation of
plexuses, the constant change in the direction taken by fibres, and the same crossing
and intercrossing which have been noticed in other situations. In fact the nervous
distribution in these organs presents the same typical arrangement as is met with in
other tissues, but it is compressed into a very small space.
Now with regard to the epithelium-like structure upon the summit, it has been
shown that the nerve-fibres are probably continuous with the material lying between
the large nuclei. In fact if the interpretation of the appearances which I have given
be correct, the arrangement may be expressed thus :■ —
MINUTE ANATOMY OF THE PAPILLAE OF THE FEQG’S TONGUE.
451
The material marked a (Plate XXI. fig. 2) is a continuation of the nervous structure
or tissue, while the matter marked b bears the same relation to this as the so-called
nucleus of a nerve bears to its fibre, of an epithelial cell to its wall. If this be so, the
matter which is freely exposed at the very summit of the papilla is -at least structurally
continuous with nerve-tissue, if it is not to be regarded as nerve itself. My own opinion
is that it is just as much nerve-tissue as a fine nerve-fibre is nerve-tissue, or the caudate
process of a nerve-cell is nerve-tissue. The formed matter is produced by the large
masses of germinal matter which are so very numerous, just as the formed matter of a
central nerve-cell results from changes occurring in its germinal matter.
It may not be out of place here to consider how the elaborate organ connected with
the bundle of nerve-fibres of the papilla may act during life. As already stated, the
free surface is uneven, and the arrangement is such that there are many elevations pro-
jecting, like fibres, by slightly varying distances, from the general surface. Now from
the intricate interlacement of the nerve-fibres in the summit of a papilla, as well as at
the point between this and the peculiar organ (Plate XXI. fig. 3, b), it is obvious that
a fibre given off from one coming from the extreme left of the papilla, for example, may
be situated a very short distance from a fibre coming from the opposite side. Any
object, therefore, which connects the exposed projections would produce a temporary
disturbance in the nerve-currents which are traversing these fibres, and this alteration
in the current would of course produce a change in the cell or cells which form part
of the same circuit in the nerve-centre. Any strong pressure would influence all the
fibres distributed to this delicate nervous organ.
The supposed mode of action is explained by the plan (Plate XXI. fig. 4).
Nerve-fibres ramifying upon the capillary vessels , in the connective tissue ,
and upon the muscular fibres.
Many of the so-called connective-tissue corpuscles, with their anastomosing processes
or “ tubes” are really nerve-nuclei and very fine pale nerve-fibres, as has already been
shown in observations upon the frog’s bladder. In the tongue I have followed these
fine fibres in very many specimens. They can only be seen and traced in specimens
prepared in syrup, glycerine, or other viscid medium miscible in all proportions with
water.
In Plate XXI. fig. 1 ,f and in fig. 8, one of these fine branches, coming off from
a bundle of dark-bordered fibres, is represented. Now, if examined by a low power,
this might be mistaken for a fibre of connective tissue ; but it really consists of several
very fine fibres, which in their arrangement exhibit the same peculiarities observed in
nerves ramifying in larger trunks (Plate XXII. figs. 20, 23). The fine branches divide
and subdivide, and the delicate fibres resulting from their division can be followed for a
very long distance. The finest are composed of several finer fibres, and they form
networks or plexuses, the meshes of which vary much in size.
The branches which are distributed around the capillaries, in the connective tissue,
mdccclxv. 3 Q
452
PEOFESSOE BEALE’S NEW OBSEEVATIONS UPON THE
and to the musular fibres, seem to result from the division and subdivision of the same
fibres (Plate XXI. fig. 1).
Nerves which are constantly distributed external to the capillary vessels and in the
connective tissue have been demonstrated by me (Plate XXII. fig. 15) (see Archives,
vol. iv. page 19). I consider these fibres as the afferent fibres through which an
impression conveyed from the surface or from the tissues around capillaries, influences
the motor nerves distributed to the small arteries from which the capillaries are derived.
It is probable that these nerve-fibres pass to the very same set of central cells as that
from which the vaso-motor fibres take their rise. It is through these fibres that changes
in the nutrition of the tissues may affect the circulation in the neighbouring vessels.
In these fungiform papillse, then, there are
1. The bundle of nerve-fibres which is distributed to the sensitive nervous organ at
the summit.
2. Delicate fibres which may be traced to fibres running in the same bundles as purely
sensitive fibres. These delicate fibres are distributed
a. Around the capillaries of the papilla (Plate XXI. fig. 1, i). Bee also Plate XXII.
fig. 15.
b. Some fibres ramify in the connective tissue of the simple papillse (Plate XXI.
fig. 1).
c. Some are distributed to the muscular fibres (Plate XXI. figs. 1 & 9).
Now the first and second fibres are probably sensitive, excitor, or afferent, whilst the
last must be motor. From this observation it follows that certain afferent and motor
fibres are intimately related at their distribution, a conclusion already arrived at in my
investigations upon the distribution of the nerves to the frog’s bladder, the palate, and
pharynx. Moreover I think that fine fibres passing from the plexus of sensitive fibres at
the summit of the papilla, establish here and there a structural continuity between
these and the fibres ramifying in the connective tissue and around the capillary vessels.
It is very difficult to obtain a specimen which renders this perfectly certain, but I have
been led to a similar conclusion in investigations upon the corpuscula tactus of the
human subject. The physiological interest and importance of this branch of anatomical
inquiry are so great, and it promises to lead to such important results, that it cannot be
too minutely or too patiently worked out.
Of the Muscles.
The muscular fibres of the papilla (Plate XXI. fig. 1) are the continuations of mus-
cular fibres in the substance of the tongue. They are excellent examples of branching
striped muscle. The finest branches are less than 5o,oooth of an inch in diameter, but
these exhibit the most distinct transverse markings. The markings, however, gradually
cease, and the fibre becomes a mere line, which is lost in the connective tissue at the
summit of the papilla. The arrangement will be understood if Plate XXI. figs. 1 & 9
be referred to.
MINUTE ANATOMY OE THE PAPILLAE OF THE FROG’S TONGUE.
453
The so-called nuclei or masses of germinal matter in connexion with these fine mus-
cular fibres present several points which will well repay attentive study. These masses
of germinal matter are sometimes twice or three times the width of the fibre with which
they are connected. In a paper published in Part XIV. of my ‘Archives,’ I have adduced
facts which render it probable that these nuclei or masses of germinal matter change
their position in a very remarkable manner during life.
The conclusions I have arrived at upon this point are as follows : —
The masses of germinal matter appear to move along the surface of the already-formed
muscular tissue, and as they move part of their substance becomes converted into muscle
(Plate XXII. fig. 13). It is in this way that new muscle is formed and new muscular
tissue is added to that already produced. The germinal matter itself does not diminish
in size, because it absorbs as much pabulum as will compensate for what it loses of
its own substance by conversion into tissue. In the young muscle the nucleus increases
in size.
From what I have observed, I think that these oval masses of germinal matter move
in different directions, but always in a line with the fibrillated structure, so that in
a muscle some will be moving upwards, some downwards; and when the nuclei are
arranged in rows or straight lines, the nuclei lying in adjacent lines will be moving in
opposite directions. During the formation of a muscle these masses undergo division
in two directions, longitudinally and transversely. The two masses which result from
the division of one will pass in opposite directions.
As is well known, the position of these nuclei with respect to the formed muscular
tissue is very different in different cases. Sometimes they are in the very centre of
the elementary fibre, as in the constantly-growing fibres of the heart, sometimes upon
its surface only, sometimes distributed at very equal distances throughout its sub-
stance. Wherever these nuclei are situated new muscular tissue may be produced,
and it is only in these situations that muscular tissue ever is produced ; so that by the
position of the nuclei we learn the seat of formation of new muscle at different periods
of life.
The facts which I regard as favourable to the view above expressed concerning the
movements of the masses of germinal matter of muscle, are derived from many sources,
but I will refer to some observed in the case of the muscles of the papillae of the tongue.
Here the muscular fibre is very thin and delicate, and very favourable for observation.
The mass of germinal matter is very much wider than the muscle. Often three or four
of these masses are seen close together (Plate XXI. fig. 9), while for some distance above
and below the muscular fibre is destitute of nuclei. The narrowest extremity of the
oval mass is directed in some cases towards the terminal extremity of the muscle, in
others towards its base. There are often three or four fine fibres branching off from one
stem, and gradually tapering into fine threads towards their insertion at the summit of
the papilla (Plate XXI. figs. 1 & 9). The nuclei are three or four times as wide as these
fibres. The greatest difference is observed in the distance between contiguous nuclei
3 Q 2
454
PROFESSOR BEALE’S NEW OBSERVATIONS UPON THE
connected with the very same fibre. If the muscle had gone on growing uniformly in
all parts since the earliest period of its development, the nuclei would be separated from
one another by equal distances, or by distances gradually but regularly increasing or
diminishing from one extremity of the fibre towards the other.
I think the irregular arrangement of the nuclei in these muscular fibres of the tongue
is to be accounted for by their movements. Perhaps, of a collection of these nuclei
close together, two may be moving upwards towards the narrow extremity of the muscle
which is inserted into the connective tissue, while the third may be moving in the oppo-
site direction.
In some instances a “ fault ” is observed in the production of the muscular tissue, as if .
the nucleus had bridged over a space and formed a thin layer or band of muscular
tissue, which, when fully formed, was separated by a narrow space or interval from the
rest of the muscle. See Plate XXII. fig. 12.
In cases in which the nuclei are distributed at intervals throughout the muscular
tissue, as in the large elementary fibres of the muscles of the frog, the formation of the
contractile material gradually ceases as the elementary fibre attains its full size. When
this point has been reached some of the nuclei gradually diminish in size, and their
original seat is marked by a collection of granules. These granules are sometimes
absorbed, and the seat of the original nucleus is marked by a short line which gradually
tapers at the two extremities until it is lost.
It is almost needless to say that no alteration produced by the different contractions
of the muscle in different parts, would account for the position of the nuclei observed
in the fine fibres of the papillae of the frog’s tongue.
These views, it need scarcely be said, differ entirely from those generally entertained
upon the development and formation of muscular tissue. They are supported by
detailed observations made in all classes of animals, and in the same species at different
periods of age. There are some facts in connexion with the changes occurring in disease
which afford support to this view, which involves three positions. That in the nutrition
of muscle the pabulum invariably becomes converted into germinal matter; that the
latter undergoes change, and gradually becomes contractile tissue ; and that all the con-
tractile material of muscle was once in the state of the material of which the nuclei or
masses of germinal matter are composed. It is not deposited from the blood, nor pro-
duced by the action of the nuclei at a distance, but it results from a change in the very
matter of the nucleus itself. The manner in which this occurs has been already dis-
cussed in the paper above referred to (Archives, No. XIV.). It was shown that the
oval nucleus could be followed into a very fine band of contractile tissue or fibrilla
(Plate XXII. fig. 13). We pass from the matter of the nucleus into very transparent
imperfectly-formed tissue in which no transverse lines are perceptible, and from this
into fully-developed contractile material in which the characteristic transverse markings
are fully developed.
MINUTE ANATOMY OF THE PAPILLAE OF THE FROG’S TONGUE.
455
Of the Capillaries.
The capillaries of the papilla of the frog’s tongue are remarkable for their large size.
In the common frog there is a complete vascular ring at the summit of the papilla,
through which the bundle of nerve-fibres distributed to this part pass. In the Hyla the
same is observed in some of the papillae, but the more common arrangement may be
described as a half ring or a simple loop, bent upon one side at its upper part (Plate
XXI. fig. 1).
When the large capillaries of the papilla are distended with transparent Prussian-
blue injection, their walls are seen to be of extreme tenuity and transparency. Con-
nected with the transparent tissue are numerous oval masses of germinal matter (nuclei),
which are separated from one another by very short intervals. Some of these masses
project slightly from the inner surface of the vessel into its interior, but the majority
seem to be upon its external surface. Of an oval form, many of these latter gradually
taper into thin fibres which are continuous with the tissue of which the vascular wall is
constituted. The delicate membrane constituting the vascular wall exhibits longitudinal
striae, which are probably produced in its formation, and by its external surface is con-
nected with the delicate connective tissue which forms, as it were, the basis-substance
of the papilla, and intervenes between all the important tissues which are found in it.
This is proved by the fact that the vessel is moved when the transparent connective
tissue at some distance from it is drawn in a direction from the vessel.
The most interesting point I have observed in connexion with the anatomy of these
vessels, is the existence of very fine nerve-fibres. These form a lax network around the
capillary. I have traced these fine fibres continuous with undoubted nerve-trunks in
many instances, and have followed the latter into the trunks of dark-bordered fibres,
from which the bundle in the papilla is derived. A similar arrangement of fine nerve-
fibres has been demonstrated in connexion with other capillary vessels of the frog.
These fine nerve-fibres are very distinct in several of my specimens.
I have indeed observed, in my paper published in the Transactions for 1863, contrary
to the statements of most anatomists, that capillary vessels generally are freely supplied
with nerves, but the latter and their nuclei have been regarded as connective-tissue
fibres and connective-tissue corpuscles ; I have shown in certain specimens that, of the
two fibres resulting from the subdivision of a dark-bordered fibre, one was distributed to
the fibres of voluntary muscle, while the other ramified over the vessels supplying the
muscle (Plate XXII. fig. 15). These facts, it need scarcely be said, are of great import-
ance with reference to the mechanism of nervous action.
I have not succeeded in demonstrating lymphatic vessels in the papillae of the frog’s
tongue.
Besides the various nuclei described, there are several round, oval, and variously-
shaped bodies, about the size of a frog’s blood-corpuscle, which are composed princi-
pally of minute oil-globules and granules. These are not coloured by carmine. Many
456
PROFESSOR BEALE’S NEW OBSERVATIONS UPON THE
contain a small mass of germinal matter (nucleus) in the centre, which is of course
coloured. In some of the smaller ones this mass of germinal matter is much larger in
proportion to the entire “ cell.” These bodies resemble many of the fat-cells of the
frog, and I think it probable they are of this nature. It is, however, possible that
these masses may be altered lymph-corpuscles. The Hylae which I examined had been
for some time in confinement, and contained very little adipose tissue.
Conclusions.
1. That fine nerve-fibres ramify in the connective tissue of which the simple papillae
are composed, and that connected with these nerve-fibres are oval masses of germinal
matter or nuclei, which are usually regarded as “ connective-tissue corpuscles.”
2. That neither the epithelial cells of the frog’s tongue generally, nor those covering
the simple papillae, are connected with nerve-fibres.
3. That the mass consisting of epithelium-like cells upon the summit of the fungiform
papilla, is connected with the nerve-fibres, but it is not an epithelial structure.
4. That the dark-bordered sensitive fibres constituting the bundle of nerves in the
axis of the papilla divide near its summit into numerous very fine branches, with which
nuclei are connected. Thus is formed a plexus or network of exceedingly fine fibres
upon the summit of each papilla ; from this network numerous fine fibres may be traced
into the special nervous organ, composed of epithelium-like cells upon the summit, with
every one of which nerve-fibres appear to be connected.
5. That the bundle of nerve-fibres distributed to a papilla always divides into two
bundles which pursue opposite directions. The division of the bundle may take place
just at the base of the papilla, or at some distance from it, but it always occurs.
6. That fine pale nerve-fibres pass from the same trunk of dark-bordered fibres as that
which gives off the bundle of nerves to the papilla. The fine fibres ramify —
a. Amongst the muscular fibres of the tongue.
b. Upon the vessels.
c. In the connective tissue of the tongue generally, and also in the simple papillae.
7. That the fine nucleated nerve-fibres ramify freely amongst the delicate branching
muscular fibres of the papillae, and form plexuses or networks which exhibit no nerve-
ends or terminations, nor in any case does a nerve-fibre penetrate through the sarco-
lemma or investing tissue of the fibre, or connect itself with the nuclei of the muscle.
As many of the muscular fibres are so very fine and narrow, the distribution of the nerves,
and their exact relation to the contractile tissue, can be demonstrated very distinctly in
the case of the muscles of the papillae of the frog’s tongue.
MINUTE ANATOMY OF THE PAPILLiE OF THE FEOG’S TONGUE.
457
Description of the Plates.
The figures represented in Plate XXI. illustrate the structure of the papillae of the
frog’s tongue. In fig. 1 an entire fungiform papilla only in part finished is delineated.
A portion of every tissue entering into its formation is however represented. The
structure of this papilla is most interesting, because in a very small space we have
epithelium, muscle, connective tissue, nerves of special sensation, motor nerves, distributed
to the branching muscular fibres, and nerves distributed to the capillary vessels and con-
nective tissue which are probably afferent. In the other figures the most important
structures entering into the formation of the papilla are represented very highly
magnified. Many of the preparations from which these drawings have been taken are
in my possession, and can be examined by any one desirous of seeing them. The mode
of preparation adopted is special, and has been referred to very generally in previous
papers. It is described in detail in ‘ How to Work with the Microscope.’ Each
figure is fully explained in the text beneath it, so that it is unnecessary to give a more
minute description of the illustrations in this or the following Plate.
.
.
'
'
Phil. Trans. MDCCCLXTV. PLATE XXI.
Fig. S.
-A- portion of one of
cells or nuclei conne
fine nerve fibres, form:
tiie top of the ™
after the removal of t'
J?ass fr°na the
mass on the sumrr
Pig- 4.
Pig. 3.
[ 459 ]
VIII. A Dynamical Theory of the Electromagnetic Field. By J. Clerk Maxwell, F.B.S.
Received October 27,; — Read December 8, 1864.
PART I. — INTRODUCTORY.
(1) The most obvious mechanical phenomenon in electrical and magnetical experiments
is the mutual action by which bodies in certain states set each other in motion while
still at a sensible distance from each other. The first step, therefore, in reducing these
phenomena into scientific form, is to ascertain the magnitude and direction of the force
acting between the bodies, and when it is found that this force depends in a certain
way upon the relative position of the bodies and on their electric or magnetic condition,
it seems at first sight natural to explain the facts by assuming the existence of some-
thing either at rest or in motion in each body, constituting its electric or magnetic state,
and capable of acting at a distance according to mathematical laws.
In this way mathematical theories of statical electricity, of magnetism, of the mecha-
nical action between conductors carrying currents, and of the induction of currents have
been formed. In these theories the force acting between the two bodies is treated with
reference only to the condition of the bodies and their relative position, and without
any express consideration of the surrounding medium.
These theories assume, more or less explicitly, the existence of substances the parti-
cles [of which have the property of acting on one another at a distance by attraction
or repulsion. The most complete development of a theory of this kind is that of
M. W. Weber*, who has made the same theory include electrostatic and electromagnetic
phenomena.
In doing so, however, he has found it necessary to assume that the force between
two electric particles depends on their relative velocity, as well as on their distance.
This theory, as developed by MM. W. Weber and C. Neumann!, is exceedingly
ingenious, and wonderfully comprehensive in its application to the phenomena of
statical electricity, electromagnetic attractions, induction of currents and diamagnetic
phenomena; and it comes to us with the more authority, as it has served to guide the
speculations of one who has made so great an advance in the practical part of electric
science, both by introducing a consistent system of units in electrical measurement, and
by actually determining electrical quantities with an accuracy hitherto unknown.
* Electrodynamiscbe Maassbestimmimgen. Leipzic Trans, vol. i. 1849, and Taylor’s Scientific Memoirs, vol. v.
art. xiv.
f “ Explicare tentatur quomodo fiat ut lucis planum polarizationis per vires electricas vel magneticas decli-
netur.” — Halis Saxonum, 1858;
MDCCCLXV. 3 R
460
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
(2) The mechanical difficulties, however, which are involved in the assumption of
particles acting at a distance with forces which depend on their velocities are such as
to prevent me from considering this theory as an ultimate one, though it may have been,
and may yet be useful in leading to1 the coordination of phenomena.
I have therefore preferred to seek an explanation of the fact in another direction, by
supposing them to be produced by actions which go on in the surrounding medium as
well as in the excited bodies, and endeavouring to explain the action between distant
bodies without assuming the existence of forces capable of acting directly at sensible
distances.
(3) The theory I propose may therefore be called a theory of the Electromagnetic Field ,
because it has to do with the space in the neighbourhood of the electric or magnetic bodies,
and it may be called a Dynamical Theory, because it assumes that in that space there is
matter in motion, by which the observed electromagnetic phenomena are produced.
(4) The electromagnetic field is that part of space which contains and surrounds
bodies in electric or magnetic conditions.
It may be filled with any kind of matter, or we may endeavour to render it empty of
all gross matter, as in the case of Geissler’s tubes and other so-called vacua.
There is always, however, enough of matter left to receive and transmit the undulations
of light and heat, and it is because the transmission of these radiations is not greatly
altered when transparent bodies of measurable density are substituted for the so-called
vacuum, that we are obliged to admit that the undulations are those of an sethereal
substance, and not of the gross matter, the presence of which merely modifies in some
way the motion of the sether.
We have therefore some reason to believe, from the phenomena of light and heat,
that there is an sethereal medium filling space and permeating bodies, capable of being
set in motion and of transmitting that motion from one part to another, and of com-
municating that motion to gross matter so as to heat it and affect it in various ways.
(5) Now the energy communicated to the body in heating it must have formerly
existed in the moving medium, for the undulations had left the source of heat some time
before they reached the body, and during that time the energy must have been half in
the form of motion of the medium and half in the form of elastic resilience. From
these considerations Professor W. Thomson has argued *, that the medium must have a
density capable of comparison with that of gross matter, and has even assigned an infe-
rior limit to that density.
(6) We may therefore receive, as a datum derived from a branch of science inde-
pendent of that with which we have to deal, the existence of a pervading medium, of
small but real density, capable of being set in motion, and of transmitting motion from
one part to another with great, but not infinite, velocity.
Hence the parts of this medium must be so connected that the motion of one part
* “ On the Possible Density of the Luminiferous Medium, and on the Mechanical Value of a Cubic Mile of
Sunlight,” Transactions of the Royal Society of Edinburgh (1854), p. 57.
PEOFESSOE CLEEK MAXWELL OX THE ELECTEOM A GXETIC FIELD.
461
depends in some way on the motion of the rest ; and at the same time these connexions
must be capable of a certain kind of elastic yielding, since the communication of motion
is not instantaneous, but occupies time.
The medium is therefore capable of receiving and storing up two kinds of energy,
namely, the “ actual ” energy depending on the motions of its parts, and “ potential ”
energy, consisting of the work which the medium will do in recovering from displace-
ment in virtue of its elasticity.
The propagation of undulations consists in the continual transformation of one of
these forms of energy into the other alternately, and at any instant the amount of
energy in the whole medium is equally divided, so that half is energy of motion, and
half is elastic resilience.
(7) A medium having such a constitution may be capable of other kinds of motion
and displacement than those which produce the phenomena of light and heat, and some
of these may be of such a kind that they may be evidenced to our senses by the pheno-
mena they produce.
(8) Now we know that the luminiferous medium is in certain cases acted on by
magnetism ; for Faeaday * discovered that when a plane polarized ray traverses a trans-
parent diamagnetic medium in the direction of the lines of magnetic force produced by
magnets or currents in the neighbourhood, the plane of polarization is caused to rotate.
This rotation is always in the direction in which positive electricity must be carried
round the diamagnetic body in order to produce the actual magnetization of the field.
M. VEKDETf has since discovered that if a paramagnetic body, such as solution of
perchloride of iron in ether, be substituted for the diamagnetic body, the rotation is in
the opposite direction.
Now Professor W. Thomson^ has pointed out that no distribution of forces acting
between the parts of a medium whose only motion is that of the luminous vibrations, is
sufficient to account for the phenomena, but that we must admit the existence of a
motion in the medium depending on the magnetization, in addition to the vibratory
motion which constitutes light.
It is true that the rotation by magnetism of the plane of polarization has been
observed only in media of considerable density ; but the properties of the magnetic field
are not so much altered by the substitution of one medium for another, or for a vacuum,
as to allow us to suppose that the dense medium does anything more than merely modify
the motion of the ether. We have therefore warrantable grounds for inquiring whether
there may not be a motion of the ethereal medium going on wherever magnetic effects
are observed, and we have some reason to suppose that this motion is one of rotation,
having the direction of the magnetic force as its axis.
(9) We may now consider another phenomenon observed in the electromagnetic
* Experimental Eesearches, Series 19.
t Comptes Eendus (1856, second half year, p. 529, and 1857, first half year, p. 1209).
+ Proceedings of the Eoyal Society, June 1856 and June 1861.
3 e 2
462 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
field. When a body is moved across the lines of magnetic force it experiences what is
called an electromotive force ; the two extremities of the body tend to become oppo-
sitely electrified, and an electric current tends to flow through the body. When the
electromotive force is sufficiently powerful, and is made to act on certain compound
bodies, it decomposes them, and causes one of their components to pass towards one
extremity of the body, and the other in the opposite direction.
Here we have evidence of a force causing an electric current in spite of resist-
ance; electrifying the extremities of a body in opposite ways, a condition which is
sustained only by the action of the electromotive force, and which, as soon as that force
is removed, tends, with an equal and opposite force, to produce a counter current through
the body and to restore the original electrical state of the body ; and finally, if strong
enough, tearing to pieces chemical compounds and carrying their components in oppo-
site directions, while their natural tendency is to combine, and to combine with a force
which can generate an electromotive force in the reverse direction.
This, then, is a force acting on a body caused by its motion through the electro-
magnetic field, or by changes occurring in that field itself ; and the effect of the force is
either to produce a current and heat the body, or to decompose the body, or, when it
can do neither, to put the body in a state of electric polarization, — a state of constraint
in which opposite extremities are oppositely electrified, and from which the body tends
to relieve itself as soon as the disturbing force is removed.
(10) According to the theory which. I propose to explain, this “electromotive force”
is the force called into play during the communication of motion from one part of the
medium to another, and it is by means of this force that the motion of one part causes
motion in another part. When electromotive force acts on a conducting circuit, it pro-
duces a current, which, as it meets with resistance, occasions a continual transformation
of electrical energy into heat, which is incapable of being restored again to the form of
electrical energy by any reversal of the process.
(11) But when electromotive force acts on a dielectric it produces a state of polari-
zation of its parts similar in distribution to the polarity of the parts of a mass of iron
under the influence of a magnet, and like the magnetic polarization, capable of being
described as a state in which every particle has its opposite poles in opposite con-
ditions *.
In a dielectric under the action of electromotive force, we may conceive that the
electricity in each molecule is so displaced that one side is rendered positively and the
other negatively electrical, but that the electricity remains entirely connected with the
molecule, and does not pass from one molecule to another. The effect of this action on
the whole dielectric mass is to produce a general displacement of electricity in a cer-
tain direction. This displacement does not amount to a current, because when it has
attained to a certain value it remains constant, but it is the commencement of a current,
and its variations constitute currents in the positive or the negative direction according
* Faeaday, Exp. Res. Series XI. ; Mossotti, Mem. della Soc. Italiana (Modena), vol. xxiv. part 2. p. 49.
PEOFESSOE CLEEK MAXWELL ON THE ELECTEOMAGNETIC FIELD.
463
as the displacement is increasing or decreasing. In the interior of the dielectric there
is no indication of electrification, because the electrification of the surface of any molecule
is neutralized by the opposite electrification of the surface of the molecules in contact
with it ; but at the bounding surface of the dielectric, where the electrification is not
neutralized, we find the phenomena which indicate positive or negative electrification.
The relation between the electromotive force and the amount of electric displacement
it produces depends on the nature of the dielectric, the same electromotive force pro-
ducing generally a greater electric displacement in solid dielectrics, such as glass or
sulphur, than in air.
(12) Here, then, we perceive another effect of electromotive force, namely, electric
displacement, which according to our theory is a kind of elastic yielding to the action
of the force, similar to that which takes place in structures and machines owing to the
want of perfect rigidity of the connexions.
(13) The practical investigation of the inductive capacity of dielectrics is rendered
difficult on account of two disturbing phenomena. The first is the conductivity of the
dielectric, which, though in many cases exceedingly small, is not altogether insensible.
The second is the phenomenon called electric absorption *, in virtue of which, when the
dielectric is exposed to electromotive force, the electric displacement gradually increases,
and when the electromotive force is removed, the dielectric does not instantly return to
its primitive state, but only discharges a portion of its electrification, and when left to
itself gradually acquires electrification on its surface, as the interior gradually becomes
depolarized. Almost all solid dielectrics exhibit this phenomenon, which gives rise to
the residual charge in the Leyden jar, and to several phenomena of electric cables
described by Mr. F. Jenkin f.
(14) We have here two other kinds of yielding besides the yielding of the perfect
dielectric, which we have compared to a perfectly elastic body. The yielding due to
conductivity may be compared to that of a viscous fluid (that is to say, a fluid having
great internal friction), or a soft solid on which the smallest force produces a permanent
alteration of figure increasing with the time during which the force acts. The yielding
due to electric absorption may be compared to that of a cellular elastic body containing
a thick fluid in its cavities. Such a body, when subjected to pressure, is compressed by
degrees on account of the gradual yielding of the thick fluid ; and when the pressure is
removed it does not at once recover its figure, because the elasticity of the substance of
the body has gradually to overcome the tenacity of the fluid before it can regain com-
plete equilibrium.
Several solid bodies in which no such structure as we have supposed can be found,
seem to possess a mechanical property of this kind $ ; and it seems probable that the
* Faraday, Exp. Ees. 1233-1250.
t Eeports of British Association, 1859, p. 248 ; and Eeport of Committee of Board of Trade on Submarine
Cables, pp. 136 & 464.
t As, for instance, the composition of glue, treacle, &c., of which small plastic figures are made, which after
being distorted gradually recover their shape.
464 PROFESSOR CLERK MAXWELL OX TJIE ELECTROMAGNETIC FIELD.
same substances, if dielectrics, may possess the analogous electrical property, and if
magnetic, may have corresponding properties relating to the acquisition, retention, and
loss of magnetic polarity.
(15) It appears therefore that certain phenomena in electricity and magnetism lead
to the same conclusion as those of optics, namely, that there is an sethereal medium
pervading all bodies, and modified only in degree by their presence ; that the parts of
this medium are capable of being set in motion by electric currents and magnets ; that
this motion is communicated from one part of the medium to another by forces arising
from the connexions of those parts ; that under the action of these forces there is a
certain yielding depending on the elasticity of these connexions ; and that therefore
energy in two different forms may exist in the medium, the one form being the actual
energy of motion of its parts, and the other being the potential energy stored up in the
connexions, in virtue of their elasticity.
(16) Thus, then, we are led to the conception of a complicated mechanism capable
of a vast variety of motion, but at the same time so connected that the motion of one
part depends, according to definite relations, on the motion of other parts, these motions
being communicated by forces arising from the relative displacement of the connected
parts, in virtue of their elasticity. Such a mechanism must be subject to the general
laws of Dynamics, and we ought to be able to work out all the consequences of its
motion, provided we know the form of the relation between the motions of the parts.
(17) We know that when an electric current is established in a conducting circuit,
the neighbouring part of the field is characterized by certain magnetic properties, and
that if two circuits are in the field, the magnetic properties of the field due to the two
currents are combined. Thus each part of the field is in connexion with both currents,
and the two currents are put in connexion with each other in virtue of their con-
nexion with the magnetization of the field. The first result of this connexion that 1
propose to examine, is the induction of one current by another, and by the motion of
conductors in the field.
The second result, which is deduced from this, is the mechanical action between con-
ductors carrying currents. The phenomenon of the induction of currents has been
deduced from their mechanical action by Helmholtz* and Thomson f. I have followed
the reverse order, and deduced the mechanical action from the laws of induction. I
have then described experimental methods of determining the quantities L, M, N, on
which these phenomena depend.
(18) I then apply the phenomena of induction and attraction of currents to the
exploration of the electromagnetic field, and the laying down systems of lines of mag-
netic force which indicate its magnetic properties. By exploring the same field with a
magnet, I show the distribution of its equipotential magnetic surfaces, cutting the lines
of force at right angles.
* “ Conservation of Force,” Physical Society of Berlin, 1847 ; and Taylor’s Scientific Memoirs, 1853,
p. 114.
f Reports of the British Association, 1848; Philosophical Magazine, Dec. 1851.
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
465
In order to bring these results within the power of symbolical calculation, I then
express them in the form of the General Equations of the Electromagnetic Field.
These equations express —
(A) The relation between electric displacement, true conduction, and the total
current, compounded of both.
(B) The relation between the lines of magnetic force and the inductive coefficients of
a circuit, as already deduced from the laws of induction.
(C) The relation between the strength of a current and its magnetic effects, according
to the electromagnetic system of measurement.
(D) The value of the electromotive force in a body, as arising from the motion of the
body in the field, the alteration of the field itself, and the variation of electric
potential from one part of the field to another.
(E) The relation between electric displacement, and the electromotive force which
produces it.
(F) The relation between an electric current, and the electromotive force which pro-
duces it.
(G) The relation between the amount of free electricity at any point, and the electric
displacements in the neighbourhood.
(H) The relation between the increase or diminution of free electricity and the elec-
tric currents in the neighbourhood.
There are twenty of these equations in all, involving twenty variable quantities.
(19) I then express in terms of these quantities the intrinsic energy of the Electro-
magnetic Field as depending partly on its magnetic and partly on its electric polariza-
tion at every point.
From this I determine the mechanical force acting, 1st, on a moveable conductor
carrying an electric current ; 2ndly, on a magnetic pole ; 3rdly, on an electrified body.
The last result, namely, the mechanical force acting on an electrified body, gives rise
to an independent method of electrical measurement founded on its electrostatic effects.
The relation between the units employed in the two methods is shown to depend on
what I have called the “ electric elasticity” of the medium, and to be a velocity, which
has been experimentally determined by MM. Weber and Kohlrausch.
I then show how to calculate the electrostatic capacity of a condenser, and the
specific inductive capacity of a dielectric.
The case of a condenser composed of parallel layers of substances of different electric
resistances and inductive capacities is next examined, and it is shown that the pheno-
menon called electric absorption will generally occur, that is, the condenser, when
suddenly discharged, will after a short time show signs of a residual charge.
(20) The general equations are next applied to the case of a magnetic disturbance
propagated through a non-conducting field, and it is shown that the only disturbances
which can be so propagated are those which are transverse to the direction of propaga-
tion, and that the velocity of propagation is the velocity v, found from experiments such
466 PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
as those of Weber, which expresses the number of electrostatic units of electricity
which are contained in one electromagnetic unit.
This velocity is so nearly that of light, that it seems we have strong reason to con-
clude that light itself (including radiant heat, and other radiations if any) is an electro-
magnetic disturbance in the form of waves propagated through the electromagnetic field
according to electromagnetic laws. If so, the agreement between the elasticity of the
medium as calculated from the rapid alternations of luminous vibrations, and as found
by the slow processes of electrical experiments, shows how perfect and regular the
elastic properties of the medium must be when not encumbered with any matter denser
than air. If the same character of the elasticity is retained in dense transparent bodies,
it appears that the square of the index of refraction is equal to the product of the
specific dielectric capacity and the specific magnetic capacity. Conducting media are
shown to absorb such radiations rapidly, and therefore to be generally opaque.
The conception of the propagation of transverse magnetic disturbances to the exclu-
sion of normal ones is distinctly set forth by Professor Faraday * in his “ Thoughts on
Kay Vibrations.” The electromagnetic theory of light, as proposed by him, is the same
in substance as that which I have begun to develope in this paper, except that in 1846
there were no data to calculate the velocity of propagation.
(21) The general equations are then applied to the calculation of the coefficients of
mutual induction of two circular currents and the coefficient of self-induction in a coil.
The want of uniformity of the current in the different parts of the section of a wire at
the commencement of the current is investigated, I believe for the first time, and the
consequent correction of the coefficient of self-induction is found.
These results are applied to the calculation of the self-induction of the coil used in
the experiments of the Committee of the British Association on Standards of Electric
Resistance, and the value compared with that deduced from the experiments.
PART II. — OX ELECTROMAGNETIC INDUCTION.
Electromagnetic Momentum of a Current.
(22) We may begin by considering the state of the field in the neighbourhood of an
electric current. We know that magnetic forces are excited in the field, their direction
and magnitude depending according to known laws upon the form of the conductor
carrying the current. When the strength of the current is increased, all the magnetic
effects are increased in the same proportion. Now, if the magnetic state of the field
depends on motions of the medium, a certain force must be exerted in order to increase
or diminish these motions, and when the motions are excited they continue, so that the
effect of the connexion between the current and the electromagnetic field surrounding
it, is to endow the current with a kind of momentum, just as the connexion between
the driving-point of a machine and a fly-wheel endows the driving-point with an addi-
* Philosophical Magazine, May 1846, or Experimental Researches, iii. p. 447.
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
467
tional momentum, which may be called the momentum of the fly-wheel reduced to
the driving-point. The unbalanced force acting on the driving-point increases this
momentum, and is measured by the rate of its increase.
In the case of electric currents, the resistance to sudden increase or diminution of
strength produces effects exactly like those of momentum, but the amount of this mo-
mentum depends on the shape of the conductor and the relative position of its different
parts.
Mutual Action of two Currents.
(23) If there are two electric currents in the field, the magnetic force at any point is
that compounded of the forces due to each current separately, and since the two currents
are in connexion with every point of the field, they will be in connexion with each other,
so that any increase or diminution of the one will produce a force acting with or con-
trary to the other.
Dynamical Illustration of Deduced Momentum.
(24) As a dynamical illustration, let us suppose a body C so connected with two
independent driving-points A and B that its velocity is p times that of A together with
q times that of B. Let u be the velocity of A, v that of B, and w that of C, and let lx,
ly, Iz be their simultaneous displacements, then by the general equation of dynamics*,
C^lz=lLlx+Yly,
where X and Y are the forces acting at A and B.
But
dw du dv
dt=P~di+2Jt'
and
lz—plx-\-qly.
Substituting, and remembering that lx and ly are independent,
X~=jt(Cfu+Cpqv), |
^=Jt(Cpqu+Cq2v).
We may call Cp2u-\-Cpqv the momentum of C referred to A, and Cpqu-\-Cq2v its
momentum referred to B ; then we may say that the effect of the force X is to increase the
momentum of C referred to A, and that of Y to increase its momentum referred to B.
If there are many bodies connected with A and B in a similar way but with different
values of p and q, we may treat the question in the same way by assuming
L=2(Cp2), M=2(Cp2), andN=2(C f),
* Lagrange, Mec. Anal. ii. 2. § 5.
3 s
MDCCCLXV.
468
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
where the summation is extended to all the bodies with their proper values of C, p, and q.
Then the momentum of the system referred to A is
and referred to B,
and we shall have
L u +My,
Mu+m,
X=|(L»+Mi;),- 1
7 • (2)
Y = |(M«+N«),
where X and Y are the external forces acting on A and B.
(25) To make the illustration more complete we have only to suppose that the
motion of A is resisted by a force proportional to its velocity, which we may call Rw,
and that of B by a similar force, which we may call Sv, R and S being coefficients of
resistance. Then if | and q are the forces on A and B
!=X+Rm=Rm+^(Lm+Mv),
,=y+So=Si)+J(M«+NiI)
(3)
If the velocity of A be increased at the rate then in order to prevent B from moving
a force, ^=^(M u) must be applied to it.
This effect on B, due to an increase of the velocity of A, corresponds to the electro-
motive force on one circuit arising from an increase in the strength of a neighbouring
circuit.
This dynamical illustration is to be considered merely as assisting the reader to under-
stand what is meant in mechanics by Reduced Momentum. The facts of the induction
of currents as depending on the variations of the quantity called Electromagnetic Mo-
mentum, or Electrotonic State, rest on the experiments of Faraday *, Felici f , &c.
Coefficients of Induction for Two Circuits.
(26) In the electromagnetic field the values of L, M, N depend on the distribution
of the magnetic effects due to the two circuits, and this distribution depends only on
the form and relative position of the circuits. Hence L, M, N are quantities depending
on the form and relative position of the circuits, and are subject to variation with the
motion of the conductors. It will be presently seen that L, M, N are geometrical
quantities of the nature of lines, that is, of one dimension in space ; L depends on the
form of the first conductor, which we shall call A, N on that of the second, which we
shall call B, and M on the relative position of A and B.
(27) Let | be the electromotive force acting on A, x the strength of the current, and
* Experimental Researches, Series I., LX. f Annales de Chimie, ser. 3. xxxiv. (1852) p. 64.
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
469
R the resistance, then R# will be the resisting force. In steady currents the electro-
motive force just balances the resisting force, but in variable currents the resultant
force |=Ra is expended in increasing the “electromagnetic momentum,” using the
word momentum merely to express that which is generated by a force acting during a
time, that is, a velocity existing in a body.
In the case of electric currents, the force in action is not ordinary mechanical force, at
least we are not as yet able to measure it as common force, but we call it electromotive
force, and the body moved is not merely the electricity in the conductor, but something
outside the conductor, and capable of being affected by other conductors in the neighbour-
hood carrying currents. In this it resembles rather the reduced momentum of a driving-
point of a machine as influenced by its mechanical connexions, than that of a simple
moving body like a cannon ball, or water in a tube.
Electromagnetic Relations of two Conducting Circuits.
(28.) In the case of two conducting circuits, A and B, we shall assume that the
electromagnetic momentum belonging to A is
La ~j~ ATy,
and that belonging to B,
Ma -f- Ny,
where L, M, N correspond to the same quantities in the dynamical illustration, except
that they are supposed to be capable of variation when the conductors A or B are
moved.
Then the equation of the current x in A will be
i=RA+^(LA-f My), (4)
and that of y in B
^=Sy + ^(Ma+%), (5)
where g and rt are the electromotive forces, x and y the currents, and R and S the
resistances in A and B respectively.
Induction of one Current by another.
(29) Case 1st. Let there be no electromotive force on B, except that which arises
from the action of A, and let the current of A increase from 0 to the value x , then
Sy+^Ma+Ny^O,
whence •••■».
that is, a quantity of electricity Y, being the total induced current, will flow through B
when x rises from 0 to x. This is induction by variation of the current in the primary
3 s 2
470 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
conductor. When M is positive, the induced current due to increase of the primary
current is negative.
Induction by Motion of Conductor.
(30) Case 2nd. Let x remain constant, and let M change from M to M', then
so that if M is increased, which it will he by the primary and secondary circuits
approaching each other, there will be a negative induced current, the total quantity of
electricity passed through B being Y.
This is induction by the relative motion of the primary and secondary conductors.
Equation of Work and Energy.
(31) To form the equation between work done and energy produced, multiply (1) by
x and (2) by y , and add
e®+w=B^+Sy>+*^(Lic+My)+y|(M*+%). (8)
Here %x is the work done in unit of time by the electromotive force £ acting on the
current x and maintaining it, and v\y is the work done by the electromotive force ri.
Hence the left-hand side of the equation represents the work done by the electromotive
forces in unit of time.
Heat produced by the Current.
(32) On the other side of the equation we have, first,
R#2+S/=H, (9)
which represents the work done in overcoming the resistance of the circuits in unit of
time. This is converted into heat. The remaining terms represent work not converted
into heat. They may be written
i^(I^+2Mqr+N,f) + i
Intrinsic Energy of the Currents.
(33) If L, M, N are constant, the whole work of the electromotive forces which is
not spent against resistance will be devoted to the development of the currents. The
whole intrinsic energy of the currents is therefore
iLr2+M^+i%2=E (10)
This energy exists in a form imperceptible to our senses, probably as actual motion, the
seat of this motion being not merely the conducting circuits, but the space surrounding
them.
PROFESS OE CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD,
471
Mechanical Action between Conductors.
(34) The remaining terms,
ldL
2 dt
t‘2+^/ + ^N
Tty
:=W
(H)
represent the work done in unit of time arising from the variations of L, M, and N, or,
what is the same thing, alterations in the form and position of the conducting circuits
A and B.
Now if work is done when a body is moved, it must arise from ordinary mechanical
force acting on the body while it is moved. Hence this part of the expression shows
that there is a mechanical force urging every part of the conductors themselves in that
direction in which L, M, and N will be most increased.
The existence of the electromagnetic force between conductors carrying currents is
therefore a direct consequence of the joint and independent action of each current on
the electromagnetic field. If A and B are allowed to approach a distance ds, so as to
increase M from M to M' while the currents are x and y, then the work done will be
and the force in the direction of ds will be
dM
-df^
(12)
and this will be an attraction if x and y are of the same sign, and if M is increased as
A and B approach.
It appears, therefore, that if we admit that the unresisted part of electromotive force
goes on as long as it acts, generating a self-persistent state of the current, which
we may call (from mechanical analogy) its electromagnetic momentum, and that this
momentum depends on circumstances external to the conductor, then both induction of
currents and electromagnetic attractions may be proved by mechanical reasoning.
What I have called electromagnetic momentum is the same quantity which is called
by Faraday* the electrotonic state of the circuit, every change of which involves the
action of an electromotive force, just as change of momentum involves the action of
mechanical force.
If, therefore, the phenomena described by Faraday in the Ninth Series of his Expe-
rimental Researches were the only known facts about electric currents, the laws of
Ampere relating to the attraction of conductors carrying currents, as well as those
of Faraday about the mutual induction of currents, might be deduced by mechanical
reasoning.
In order to bring these results within the range of experimental verification, I shall
next investigate the case of a single current, of two currents, and of the six currents
in the electric balance, so as to enable the experimenter to determine the values of
L, M, N.
* Experimental Researches, Series I. 60, &c.
472 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
Case of a single Circuit.
(35) The equation of the current x in a circuit whose resistance is R, and whose
coefficient of self-induction is L, acted on by an external electromotive force f, is
I— (13)
When | is constant, the solution is of the form
x=b-\-{a— b)e~i:\
where a is the value of the current at the commencement, and b is its final value.
The total quantity of electricity which passes in time t, where t is great, is
\xdt=bt+(a-b)^ (14)
<i/0 ^
The value of the integral of x 2 with respect to the time is
(15)
The actual current changes gradually from the initial value a to the final value $, but
the values of the integrals of x and x 2 are the same as if a steady current of intensity
^(a+£) were to flow for a time 2^, and were then succeeded by the steady current b.
The time 2^ is generally so minute a fraction of a second, that the effects on the galvano-
meter and dynamometer may be calculated as if the impulse were instantaneous.
If the circuit consists of a battery and a coil, then, when the circuit is first completed,
the effects are the same as if the current had only half its final strength during the time
2 This diminution of the current, due to induction, is sometimes called the counter-
current.
(36) If an additional resistance r is suddenly thrown into the circuit, as by breaking
contact, so as to force the current to pass through a thin wire of resistance r, then the
original current is a= -JL and the final current is b=-Ji— .
& R R + r
The current of induction is then + r , and continues for a time 2=-*^-. This
2 R(R + ?-)’ R + r
current is greater than that which the battery can maintain in the two wires R and r,
and may be sufficient to ignite the thin wire r.
When contact is broken by separating the wires in air, this additional resistance is
given by the interposed air, and since the electromotive force across the new resistance
is very great, a spark will be forced across.
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
47 3
If the electromotive force is of the form E sin^£, as in the case of a coil revolving in
a magnetic field, then
X—~ sin (pt — a),
where g2=R2-|-L 2_p2, and tan «=-,(-■
Case of two Circuits.
(37) Let K be the primary circuit and S the secondary circuit, then we have a case
similar to that of the induction coil.
The equations of currents are those marked A and B, and we may here assume
L, M, N as constant because there is no motion of the conductors. The equations
then become
B*'+L5+M ;M|
'Sy+M§+N|=0.{
To find the total quantity of electricity which passes, we have only to integrate these
equations with respect' to t\ then if^0,y0be the strengths of the currents at time 0,
and Wi , yx at time t, and if X, Y be the quantities of electricity passed through each
circuit during time t,
X= jr {^+L(ff0— ^) 7%-?/,)},
(14*)
Y =4{ M(^-^)+N(y0-^)}.
When the circuit R is completed, then the total currents up to time t , when t is
great, are found by making
then
tf0=0, y o 0 , y, = 0;
X=.,(i-|), Y=-~s,. (15*)
The value of the total counter-current in It is therefore independent of the secondary
circuit, and the induction current in the secondary circuit depends only on M, the
coefficient of induction between the coils, S the resistance of the secondary coil, and
the final strength of the current in It.
When the electromotive force f ceases to act, there is an extra current in the pri-
mary circuit, and a positive induced current in the secondary circuit, whose values are
equal and opposite to those produced on making contact.
(38) All questions relating to the total quantity of transient currents, as measured
by the impulse given to the magnet of the galvanometer, may be solved in this way
without the necessity of a complete solution of the equations. The heating effect of
474
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
the current, and the impulse it gives to the suspended coil of Weber’s dynamometer,
depend on the square of the current at every instant during the short time it lasts.
Hence we must obtain the solution of the equations, and from the solution we may find
the effects both on the galvanometer and dynamometer ; and we may then make use of
the method of Weber for estimating the intensity and duration of a current uniform
while it lasts which would produce the same effects.
(39) Let w1? n2 be the roots of the equation
(LN-M>2 + (RN+LS>+RS=0, (16)
and let the primary coil be acted on by a constant electromotive force Rc, so that c is
the constant current it could maintain ; then the complete solution of the equations for
making contact is
» c n\ni
S nl— n2
G
-+NW
+N e^+S-
(17)
cM
s=-w
{e^-e^} (18)
From these we obtain for calculating the impulse on the dynamometer,
j 'a*dt=
hfdt=
2 J / 3. _ 1 iyi
{ 2 R— 2rn+LS
21 M2R
CsS(RN + LS)’
(19)
(20)
The effects of the current in the secondary coil on the galvanometer and dynamometer
are the same as those of a uniform current
1 „ MR
2 CRN + LS
(40) The equation between work and energy may be easily verified. The work done
by the electromotive force is
%§xdt=c-(R,t—L).
Work done in overcoming resistance and producing heat,
R j#2<ft + Sjy = c2(R£ — f L).
Energy remaining in the system,
=ic2 L.
(41) If the circuit R is suddenly and completely interrupted while carrying a current
c, then the equation of the current in the secondary coil would be
M »,
y=c-e » .
This current begins with a value c ^ , and gradually disappears.
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
475
The total quantity of electricity is <7 ^ , and the value of §y2dt is c2 •
The effects on the galvanometer and dynamometer are equal to those of a uniform
current 4 c ^ for a time 2 •
2 N S
The heating effect is therefore greater than that of the current on making contact.
(42) If an electromotive force of the form £=E cos pt acts on the circuit R, then if
the circuit S is removed, the value of x will be
E
x= ^ sin (pt—ot),
where
A2=R2+Ly,
and
tan
The effect of the presence of the circuit S in the neighbourhood is to alter the value
of A and a, to that which they would be if R become
and L became
R+y
MS
S2+p2N2’
T » MN
L'-JP S2+/2N2‘
Hence the effect of the presence of the circuit S is to increase the apparent resistance and
diminish the apparent self-induction of the circuit R.
On the Determination of Coefficients of Induction by the Electric Balance.
(43) The electric balance consists of six con-
ductors joining four points, A C D E, two and two.
One pair, A C, of these points is connected through
the battery B. The opposite pair, D E, is connected
through the galvanometer G. Then if the resistances
of the four remaining conductors are represented by
P, Q, R, S, and the currents in them by x, x—z, y,
and y-\-z , the current through G will be z. Let the
potentials at the four points be A, C, D, E. Then the conditions of steady currents may
be found from the equations
P*=A — D Q(x—z)=D—C, I
R^=A — E S(y+z)=E-C, i (21)
Gs=D— E B(x+y)= - A+C+F. ]
Solving these equations for z, we find
■e
p+q+r+s+b(p+ r) (q+s) +g(p+q) (r+i) +p^|s(p+q+r+s^}— f(ps~qr)-
MDCCCLXV.
3 T
476 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
In this expression F is the electromotive force of the battery, z the current through
the galvanometer when it has become steady. P, Q, R, S the resistances in the four
arms. B that of the battery and electrodes, and G that of the galvanometer.
(44) If PS=QR, then z= 0, and there will be no steady current, but a transient
current through the galvanometer may be produced on making or breaking circuit on
account of induction, and the indications of the galvanometer may be used to determine
the coefficients of induction, provided we understand the actions which take place.
We shall suppose PS=QR, so that the current z vanishes when sufficient time is
allowed, and
tffiP+QWR+Sl— F(P+Q)(R + S)
(P + Q)(R + S)+B(P+Q)(R+S)
Let the induction coefficients between P, Q, R S, be
given by the following Table, the coefficient of induction
of P on itself being p, between P and Q, h, and so on.
Let g be the coefficient of induction of the galvanometer
on itself, and let it be out of the reach of the inductive
influence of P, Q, R, S (as it must be in order to avoid
direct action of P, Q, R, S on the needle). Let X, Y, Z be the integrals of x, y , z
with respect to t. At making contact x, y , z are zero. After a time z disappears, and
x and y reach constant values. The equations for each conductor will therefore be
P Q R S
P p h k l
Q li g m n
R k m r o
S l n o s
PX +{pJrh )x+(k +Z )y=jAtf£— §Ddt,
Q(X — )x-\-(in-\-n)y=^Ddt—^Cdt,
RY -\-(k-\-m)x-{-(r -\-o)y=§Adt—]l!idt,
S(Y+Z) +(£ +n )x+(o +s)y=ftdt-$Cdt,
GZ =§Dtd —§Edt.
(24)
Solving these equations for Z, we find
Z{p+4+l+i+B(p+R) (^+s)+G(p+^) (R+s)+PaRs(P+Q+Il+S)}
= ~FI^{p~Q“R+i+/i(p~Q) +^(l-p) +/(i+s) “m(p+|)
(25)
(45) Now let the deflection of the galvanometer by the instantaneous current whose
intensity is Z be a.
Let the permanent deflection produced by making the ratio of PS to QR, § instead of
unity, be 0,
Also let the time of vibration of the galvanometer needle from rest to rest be T.
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
477
Then calling the quantity
p~Q~R+ii+K^_6) +Ki~s) +oG~s) =*■
we find
Z 2 sin T t
2 tail 0 5T 1 — q
(27)
In determining r by experiment, it is best to make the alteration of resistance in one
of the arms by means of the arrangement described by Mr. Jenkin in the Report of the
British Association for 1863, by which any value of g from 1 to T01 can be accurately
measured.
We observe (a) the greatest deflection due to the impulse of induction when the
galvanometer is in circuit, when the connexions are made, and when the resistances are
so adjusted as to give no permanent current.
We then observe (/3) the greatest deflection produced by the permanent current when
the resistance of one of the arms is increased in the ratio of 1 to g, the galvanometer
not being in circuit till a little while after the connexion is made with the battery.
In order to eliminate the effects of resistance of the air, it is best to vary g till j3 = 2a
nearly; then . _ . ,
W
If all the arms of the balance except P consist of resistance coils of very fine wire of
no great length and doubled before being coiled, the induction coefficients belonging to
these coils will be insensible, and r will be reduced to ^ . The electric balance there-
fore affords the means of measuring the self-induction of any circuit whose resistance is
known.
(46) It may also be used to determine the coefficient of induction between two
circuits, as for instance, that between P and S which we have called m ; but it would be
more convenient to measure this by directly measuring the current, as in (37), without
using the balance. We may also ascertain the equality of ^ and F by there being no
current of induction, and thus, when we know the value of p, we may determine that of
q by a more perfect method than the comparison of deflections.
Exploration of the Electromagnetic Field.
(47) Let us now suppose the primary circuit A to be of invariable form, and let us
explore the electromagnetic field by means of the secondary circuit B, which we shall
suppose to be variable in form and position.
We may begin by supposing B to consist of a short straight conductor with its extre-
mities sliding on two parallel conducting rails, which are put in connexion at some
distance from the sliding-piece.
3 t 2
478
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
Then, if sliding the moveable conductor in a given direction increases the value of M,
a negative electromotive force will act in the circuit B, tending to produce a negative
current in B during the motion of the sliding-piece.
If a current be kept up in the circuit B, then the sliding-piece will itself tend to
move in that direction, which causes M to increase. At every point of the field there
will always be a certain direction such that a conductor moved in that direction does
not experience any electromotive force in whatever direction its extremities are turned.
A conductor carrying a current will experience no mechanical force urging it in that
direction or the opposite.
This direction is called the direction of the line of magnetic force through that point.
Motion of a conductor across such a line produces electromotive force in a direction
perpendicular to the line and to the direction of motion, and a conductor carrying a
current is urged in a direction perpendicular to the line and to the direction of the
current.
(48) We may next suppose B to consist of a very small plane circuit capable of being
placed in any position and of having its plane turned in any direction. The value of M
will be greatest when the plane of the circuit is perpendicular to the line of magnetic
force. Hence if a current is maintained in B it will tend to set itself in this position,
and will of itself indicate, like a magnet, the direction of the magnetic force.
On Lines of Magnetic Force.
(49) Let any surface be drawn, cutting the lines of magnetic force, and on this sur-
face let any system of lines be drawn at small intervals, so as to lie side by side without
cutting each other. Next, let any line be drawn on the surface cutting all these lines,
and let a second line be drawn near it, its distance from the first being such that the
value of M for each of the small spaces enclosed between these two lines and the lines
of the first system is equal to unity.
In this way let more lines be drawn so as to form a second system, so that the value of
M for every reticulation formed by the intersection of the two systems of lines is unity.
Finally, from every point of intersection of these reticulations let a line be drawn
through the field, always coinciding in direction with the direction of magnetic force.
(50) In this way the whole field will be filled with lines of magnetic force at regular
intervals, and the properties of the electromagnetic field will be completely expressed,
by them.
For, 1st, If any closed curve be drawn in the field, the value of M for that curve will
be expressed by the number of lines of force which pass through that closed curve.
2ndly. If this curve be a conducting circuit and be moved through the field, an
electromotive force will act in it, represented by the rate of decrease of the number of
lines passing through the curve.
3rdly. If a current be maintained in the circuit, the conductor will be acted on by
forces tending to move it so as to increase the number of lines passing through it, and
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
479
the amount of work done by these forces is equal to the current in the circuit multi-
plied by the number of additional lines.
4thly. If a small plane circuit be placed in the field, and be free to turn, it will place
its plane perpendicular to the lines of force. A small magnet will place itself with its
axis in the direction of the lines of force.
5thly. If a long uniformly magnetized bar is placed in the field, each pole will be
acted on by a force in the direction of the lines of force. The number of lines of force
passing through unit of area is equal to the force acting on a unit pole multiplied by a
coefficient depending on the magnetic nature of the medium, and called the coefficient
of magnetic induction.
In fluids and isotropic solids the value of this coefficient {* is the same in whatever
direction the lines of force pass through the substance, but in crystallized, strained, and
organized solids the value of p may depend on the direction of the lines of force with
respect to the axes of crystallization, strain, or growth.
In all bodies is affected by temperature, and in iron it appears to diminish as the
intensity of the magnetization increases.
On Magnetic Equipotential Surfaces.
(51) If we explore the field with a uniformly magnetized bar, so long that one of its
poles is in a very weak part of the magnetic field, then the magnetic forces will perform
work on the other pole as it moves about the field.
If we start from a given point, and move this pole from it to any other point, the
work performed will be independent of the path of the pole between the two points ;
provided that no electric current passes between the different paths pursued by the pole.
Hence, when there are no electric currents but only magnets in the field, we may
draw a series of surfaces such that the work done in passing from one to another shall
be constant whatever be the path pursued between them. Such surfaces are called
Equipotential Surfaces, and in ordinary cases are perpendicular to the Lines of mag-
netic force.
If these surfaces are so drawn that, when a unit pole passes from any one to the
next in order, unity of work is done, then the work done in any motion of a magnetic
pole will be measured by the strength of the pole multiplied by the number of surfaces
which it has passed through in the positive direction.
(52) If there are circuits carrying electric currents in the field, then there will still
be equipotential surfaces in the parts of the field external to the conductors carrying the
currents, but the work done on a unit pole in passing from one to another will depend
on the number of times which the path of the pole circulates round any of these
currents. Hence the potential in each surface will have a series of values in arith-
metical progression, differing by the work done in passing completely round one of the
currents in the field.
The equipotential surfaces will not be continuous closed surfaces, but some of them
480
PEOFESSOE CLEEK MAXWELL ON THE ELECTEOMAGNETIC FIELD.
will be limited sheets, terminating in the electric circuit as their common edge or
boundary. The number of these will be equal to the amount of work done on a unit
pole in going round the current, and this by the ordinary measurement = 4xy, where y
is the value of the current.
These surfaces, therefore, are connected with the electric current as soap-bubbles are
connected with a ring in M. Plateau’s experiments. Every current y has 4 icy surfaces
attached to it. These surfaces have the current for their common edge, and meet it at
equal angles. The form of the surfaces in other parts depends on the presence of other
currents and magnets, as well as on the shape of the circuit to which they belong.
PAET III.— GENEEAL EQUATIONS OF, THE ELECTEOMAGNETIC FIELD.
(53.) Let us assume three rectangular directions in space as the axes of x, y, and z ,
and let all quantities having direction be expressed by their components in these three
directions.
Electrical Currents (p, q, r).
(54) An electrical current consists in the transmission of electricity from one part of
a body to another. Let the quantity of electricity transmitted in unit of time across
unit of area perpendicular to the axis of x be called p, then p is the component of the
current at that place in the direction of x.
We shall use the letters p , q, r to denote the components of the current per unit of
area in the directions of x, y, z.
Electrical Displacements (f, g, h).
(55) Electrical displacement consists in the opposite electrification of the sides of a
molecule or particle of a body which may or may not be accompanied writh transmission
through the body. Let the quantity of electricity which would appear on the faces
dy.dz of an element dx , dy , dz cut from the body be f.dy.dz, then /is the component
of electric displacement parallel to x. We shall use / g, h to denote the electric
displacements parallel to x , y, z respectively.
The variations of the electrical displacement must be added to the currents p, q , r to
get the total motion of electricity, which we may call/, q\ r1, so that
(A)
r,=r+
dh
dt\
Electromotive Force (P, Q, R).
(56) Let P, Q, R represent the components of the electromotive force at any point.
Then P represents the difference of potential per unit of length in a conductor
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
481
placed in the direction of x at the given point. We may suppose an indefinitely short
wire placed parallel to x at a given point and touched, during the action of the force P,
by two small conductors, which are then insulated and removed from the influence of
the electromotive force. The value of P might then be ascertained by measuring the
charge of the conductors.
Thus if l be the length of the wire, the difference of potential at its ends will be PZ,
and if C be the capacity of each of the small conductors the charge on each will be
^CPZ. Since the capacities of moderately large conductors, measured on the electro-
magnetic system, are exceedingly small, ordinary electromotive forces arising from
electromagnetic actions could hardly be measured in this way. In practice such measure-
ments are always made with long conductors, forming closed or nearly closed circuits.
Electromagnetic Momentum (F, G, II).
(57) Let F, G, II represent the components of electromagnetic momentum at any
point of the field, due to any system of magnets or currents.
Then F is the total impulse of the electromotive force in the direction of x that would
be generated by the removal of these magnets or currents from the field, that is, if P
be the electromotive force at any instant during the removal of the system
F=fP dt.
Hence the part of the electromotive force which depends on the motion of magnets or
currents in the field, or their alteration of intensity, is
P=-~^, Q= — — , R= — 1? (29)
i it dt dt
Electromagnetic Momentum of a Circuit.
(58) Let s be the length of the circuit, then if we integrate
j*(F£+G2+n£)* (30,
round the circuit, we shall get the total electromagnetic momentum of the circuit, or the
number of lines of magnetic force which pass through it, the variations of which measure
the total electromotive force in the circuit. This electromagnetic momentum is the
same thing to which Professor Faraday has applied the name of the Electrotonic State.
If the circuit be the boundary of the elementary area dy dz , then its electromagnetic
momentum is
(f-S)**
and this is the number of lines of magnetic force which pass through the area dy dz.
Magnetic Force (a, /3, y).
(59) Let a, ft, y represent the force acting on a unit magnetic pole placed at the
given point resolved in the directions of x, y, and z.
482
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
Coefficient of Magnetic Induction (g).
(60) Let g be the ratio of the magnetic induction in a given medium to that in air
under an equal magnetizing force, then the number of lines of force in unit of area
perpendicular to x will be goc (g is a quantity depending on the nature of the medium,
its temperature, the amount of magnetization already produced, and in crystalline bodies
varying with the direction).
(61) Expressing the electric momentum of small circuits perpendicular to the three
axes in this notation, we obtain the following
liquations of Magnetic Force.
dR dR
~ _ dF dR
~ dz dx 5
dG dY
(B)
Equations of Currents.
(62) It is known from experiment that the motion of a magnetic pole in the electro-
magnetic field in a closed circuit cannot generate work unless the circuit which the pole
describes passes round an electric current. Hence, except in the space occupied by* the
electric currents,
udx+fidy-\- ydz=d<p (31)
a complete differential of <p, the magnetic potential.
The quantity <p may be susceptible of an indefinite number of distinct values, according
to the number of times that the exploring point passes round electric currents in its
course, the difference between successive values of <p corresponding to a passage com-
pletely round a current of strength c being 4src.
Hence if there is no electric current,
but if there is a current
Similarly,
— ^—0 •
dy dz -u ’
dy d$ . .
!-s=4*y'-
da. dy . ,
d/3 dx .
7U-Ty=
We may call these the Equations of Currents.
(C)
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
483
Electromotive Force in a Circuit.
(63) Let | be the electromotive force acting round the circuit A, then
«=J(ps+«S+B£)^ <32)
where ds is the element of length, and the integration is performed round the circuit.
Let the forces in the field be those due to the circuits A and B, then the electro-
magnetic momentum of A is
J’(fs+gI+hS)*=l“+m»> (33)
where u and v are the currents in A and B, and
(34)
Hence, if there is no motion of the circuit A,
d F
dV ]
dt
dx 5
dG
d'Y I
dt
~dy ’ ’
dYL
~ dt
(35)
where Y is a function of x, y, z , and t, which is indeterminate as far as regards the
solution of the above equations, because the terms depending on it will disappear on
integrating round the circuit. The quantity Y can always, however, be determined in
any particular case when we know the actual conditions of the question. The physical
interpretation of Y is, that it represents the electric potential at each point of space.
Electromotive Force on a Moving Conductor.
(64) Let a short straight conductor of length «, parallel to the axis of x , move with
a velocity whose components are and let its extremities slide along two
parallel conductors with a velocity j(. Let us find the alteration of the electro-
magnetic momentum of the circuit of which this arrangement forms a part.
In unit of time the moving conductor has travelled distances ^ along the
directions of the three axes, and at the same time the lengths of the parallel conductors
ds
included in the circuit have each been increased by
Hence the quantity
jH:+Gf+H£>
3 u
MDCCCLXV.
485 PROFESSOR CLERK MAXWELL OX THE ELECTEOMAG-NETIC FIELD.
will be increased by the following increments,
a due to motion of conductor,
\ dx dt ' dy dt ' dz dtr
~r\ due 1° lengthening of circuit.
dt \dx ds ax ds dx dsj
The total increment will therefore be
/dF dG\dy _
a \dy dx) dt a \dx dz ) dt ’
or, by the equations of Magnetic Force (8),
If P is the electromotive force in the moving conductor parallel to x referred to unit
of length, then the actual electromotive force is P a ; and since this is measured by the
decrement of the electromagnetic momentum of the circuit, the electromotive force due
to motion will be
-r, dy ndz
^—^di~^di'
(36)
(65) The complete equations of electromotive force on a moving conductor may now
be written as follows : —
Equations of Electromotive Force.
p =H
f dy
-4)
1---
Jdt
1 dt
dx
Q=H
( dz
dx\
dG
d F
f dt
-rw)
dt
-r |
R=H
dy\
dG
d^
[y dt
~a dt ,
f * dt
■ dz ' J
The first term on the right-hand side of each equation represents the electromotive
force arising, from the motion of the conductor itself. This electromotive force is per-
pendicular to the direction of motion and to the lines of magnetic force; and if a
parallelogram be drawn whose sides represent in direction and magnitude the velocity
of the conductor and the magnetic induction at that point of the field, then the area of
the parallelogram will represent the electromotive force due to the motion of the con-
ductor, and the direction of the force is perpendicular to the plane of the parallelogram.
The second term in each equation indicates the effect of changes in the position or
strength of magnets or currents in the field.
The third term shows the effect of the electric potential F. It has no effect in
causing a circulating current in a closed circuit. It indicates the existence of a force
urging the electricity to or from certain definite points in the field.
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
485
Electric Elasticity.
(66) When an electromotive force acts on a dielectric, it puts every part of the
dielectric into a polarized condition, in which its opposite sides are oppositely electri-
fied. The amount of this electrification depends on the electromotive force and on the
nature of the substance, and, in solids having a structure defined by axes, on the direc-
tion of the electromotive force with respect to these axes. In isotropic substances, if Jc
is the ratio of the electromotive force to the electric displacement, we may write the
Equations of Electric Elasticity ,
Y=lf
Q =kg,
R =kh.
Electric Resistance .
(67) When an electromotive force acts on a conductor it produces a current of elec-
tricity through it. This effect is additional to the electric displacement already con-
sidered. In solids of complex structure, the relation between the electromotive force
and the current depends on their direction through the solid. In isotropic substances,
which alone we shall here consider, if g is the specific resistance referred to unit of
volume, we may write the
Equations of Electric Resistance ,
<*=-&[ (F)
R = -fr.J
Electric Quantity.
(68) Let e represent the quantity of free positive electricity contained in unit of
volume at any part of the field, then, since this arises from the electrification of the
different parts of the field not neutralizing each other, we may write the
Equation of Free Electricity ,
6 + dx^dy^dz
0.
(G)
(69) If the medium conducts electricity, then we shall have another condition, which
may be called, as in hydrodynamics, the
Equation of Continuity,
de .dp .dq .dr q
dt dx dy dz
(H)
(70) In these equations of the electromagnetic field we have assumed twenty variable
486 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
quantities, namely,
For Electromagnetic Momentum F G H
„ Magnetic Intensity a /3y
„ Electromotive Force P Q R
„ Current due to true conduction p q r
„ Electric Displacement f g h
„ Total Current (including variation of displacement) . . p' c[ n*
„ Quantity of free Electricity e
„ Electric Potential T
Between these twenty quantities we have found twenty equations, viz.
Three equations of Magnetic Force (B)
„ Electric Currents (C)
,, Electromotive Force (D)
„ Electric Elasticity (E)
„ Electric Resistance (F)
„ Total Currents (A)
One equation of Free Electricity (G)
„ Continuity (FI)
These equations are therefore sufficient to determine all the quantities which occur
in them, provided we know the conditions of the problem. In many questions, how-
ever, only a few of the equations are required.
Intrinsic Energy of the Electromagnetic Field.
(71) We have seen (33) that the intrinsic energy of any system of currents is found
by multiplying half the current in each circuit into its electromagnetic momentum.
This is equivalent to finding the integral
E=i2(F/+G2'+Hr')<ZV (37)
over all the space occupied by currents, where p, q, r are the components of currents,
and F, G, H the components of electromagnetic momentum.
Substituting the values oif, q', r' from the equations of Currents (C), this becomes
s*K2-S)+Ke-3)+h(£ -*)b-
Integrating by parts, and remembering that
expression becomes
dG
8-zrU“*
M
dF
dz
a, /3, y vanish at an infinite distance, the
dH\ . /dG dF\] 7T
dx)~^~/\dx dy ) J ’
where the integration is to be extended over all space. Referring to the equations of
Magnetic Force (B), p. 482, this becomes
E =^2{u.(Aoi + p.[Ap+y.py}dV,
(38)
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
487
where a, /3, 7 are the components of magnetic intensity or the force on a unit magnetic
pole, and ^a, ^7 are the components of the quantity of magnetic induction, or the
number of lines of force in unit of area.
In isotropic media the value of ^ is the same in all directions, and we may express
the result more simply by saying that the intrinsic energy of any part of the magnetic
field arising from its magnetization is
Sir
p
per unit of volume, where I is the magnetic intensity.
(72) Energy may be stored up in the field in a different way, namely, by the action
of electromotive force in producing electric displacement. The work done by a variable
electromotive force, P, in producing a variable displacement, f, is got by integrating
sw
from P = 0 to the given value of P.
Since P =kf, equation (E), this quantity becomes
WV=W'=W-
Hence the intrinsic energy of any part of the field, as existing in the form of electric
displacement, is
42(P/+Qy+K/0<ZV.
The total energy existing in the field is therefore
E=2{s l(^“+A“0+w)+W+Q?+iwOpv (i)
The first term of this expression depends on the magnetization of the field, and is
explained on our theory by actual motion of some kind. The second term depends on
the electric polarization of the field, and is explained on our theory by strain of some
kind in an elastic medium.
(73) I have on a former occasion * attempted to describe a particular kind of motion
and a particular kind of strain, so arranged as to account for the phenomena. In the
present paper I avoid any hypothesis of this kind ; and in using such words as electric
momentum and electric elasticity in reference to the known phenomena of the induc-
tion of currents and the polarization of dielectrics, I wish merely to direct the mind of
the reader to mechanical phenomena which will assist him in understanding the elec-
trical ones. All such phrases in the present paper are to be considered as illustrative,
not as explanatory.
(74) In speaking of the Energy of the field, however, I wish to be understood literally.
All energy is the same as mechanical energy, whether it exists in the form of motion or
in that of elasticity, or in any other form. The energy in electromagnetic phenomena is
mechanical energy. The only question is, Where does it reside 1 On the old theories
* “ On Physical Lines of Force,” Philosophical Magazine, 1861-62.
488 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
it resides in the electrified bodies, conducting circuits, and magnets, in the form of an
unknown quality called potential energy, or the power of producing certain effects at a
distance. On our theory it resides in the electromagnetic field, in the space surrounding
the electrified and magnetic bodies, as well as in those bodies themselves, and is in two
different forms, which may be described without hypothesis as magnetic polarization
and electric polarization, or, according to a very probable hypothesis, as the motion and
the strain of one and the same medium.
(75) The conclusions arrived at in the present paper are independent of this hypo-
thesis, being deduced from experimental facts of three kinds : —
1. The induction of electric currents by the increase or diminution of neighbouring
currents according to the changes in the lines of force passing through the circuit.
2. The distribution of magnetic intensity according to the variations of a magnetic
potential.
3. The induction (or influence) of statical electricity through dielectrics.
We may now proceed to demonstrate from these principles the existence and laws of
the mechanical forces which act upon electric currents, magnets, and electrified bodies
placed in the electromagnetic field.
PART IV.— MECHANICAL ACTIONS IN THE FIELD.
Mechanical Force on a Moveable Conductor.
(76) We have shown (§§ 34 & 35) that the work done by the electromagnetic forces
in aiding the motion of a conductor is equal to the product of the current in the con-
ductor multiplied by the increment of the electromagnetic momentum due to the
motion.
Let a short straight conductor of length a move parallel to itself in the direction of
x:, with its extremities on two parallel conductors. Then the increment of the electro-
magnetic momentum due to the motion of a will be
(d¥ dx cJG dy dH dz\ .
ds ' dx ds~^~ dx ds) ll'
That due to the lengthening of the circuit by increasing the length of the parallel con-
ductors will be
The total increment is
/d F dx d F dy d1?dz\.
ytfe ds ^ dy ds dz ds J ^
aha
which is by the equations of Magnetic Force (B), p. 482,
(dG
d F\
1 d2i
fdY
dli\\
[dx
~~dy)
\d*
dx)\
aha:
Let X be the force acting along the direction of x per unit of length of the conductor,
then the work done is Xahx.
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD.
489
Let C be the current in the conductor, and letjf , qj, r' be its components, then
Xati= Calxx (^py - jg ^ ,
or X=[jjy(f — gjfir'. j
Similarly, Y—pur' — (*y]?',\ (J)
Z=^/3 p'—paq'. j
These are the equations which determine the mechanical force acting on a conductor
carrying a current. The force is perpendicular to the current and to the lines of force;
and is measured by the area of the parallelogram formed by lines parallel to the current
and lines of force, and proportional to their intensities.
Mechanical Force on a Magnet.
(77) In any part of the field not traversed by electric currents the distribution of
magnetic intensity may be represented by the differential coefficients of a function
which may be called the magnetic potential. When there are no currents in the field,
this quantity has a single value for each point. When there are currents, the potential
has a series of values at each point, but its differential coefficients have only one value,
namely,
d_l_ dp
dy dz
7-
Substituting these values of a, (3, y in the expression (equation 38) for the intrinsic
energy of the field, and integrating by parts, it becomes
-2{^(t+f + t)|F-
The expression
2(i“+w+^)dv=2^v (S9>
indicates the number of lines of magnetic force which have their origin within the
space V. Now a magnetic pole is known to us only as the origin or termination of
lines of magnetic force, and a unit pole is one which has 4x lines belonging to it, since
it produces unit of magnetic intensity at unit of distance over a sphere whose surface
is 4x.
Hence if m is the amount of free positive magnetism in unit of volume, the above
expression may be written 4xm, and the expression for the energy of the field becomes
E=-X(i<pm)dV. (40)
If there are two magnetic poles and m2 producing potentials <£>, and <p2 in the field ,
then if m2 is moved a distance dx , and is urged in that direction by a force X, then the
work done is Xdx, and the decrease of energy in the field is
<7(i(Pi+?>2)(Wi+W2)),
and these must be equal by the principle of Conservation of Energy.
490
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
Since the distribution <pl is determined by mx , and <p2 by m2, the quantities <plml and
<p2 m2 will remain constant.
It can be shown also, as Green has proved (Essay, p. 10), that
so that we get
or
m1<p2=m2®1,
'Kdx=d(m2<pl),
X=m2-~ =m2 a, ,
y
where ax represents the magnetic intensity due to m,.
Similarly, Y=m2(31,
Z—i7i2yl. j
(K)
So that a magnetic pole is urged in the direction of the lines of magnetic force with
a force equal to the product of the strength of the pole and the magnetic intensity.
(78) If a single magnetic pole, that is one pole of a very long magnet, be placed in
the field, the only solution of <p is
<t> i=
mT 1
/x r
where ml is the strength of the pole and r the distance from it.
The repulsion between two poles of strength ml and m2 is
<?<p, m^rtic
(41)
(42)
In air or any medium in which ^=1 this is simply but in other media the force
acting between two given magnetic poles is inversely proportional to the coefficient of
magnetic induction for the medium. This may be explained by the magnetization of
the medium induced by the action of the poles.
Mechanical Force on an Flectrijied Body.
(79) If there is no motion or change of strength of currents or magnets in the field,
the electromotive force is entirely due to variation of electric potential, and we shall
have (§65)
P=-^, Q= — ^ R=-^.
ax ay az
Integrating by parts the expression (I) for the energy due to electric displacement, and
remembering that P, Q, R, vanish at an infinite distance, it becomes
**{*(1 +1+1)}^
or by the equation of Free Electricity (G), p. 485,
-P(¥e)dV.
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD. 491
By the same demonstration as was used in the case of the mechanical action on a magnet,
it may be shown that the mechanical force on a small body containing a quantity e2 of
free electricity placed in a field whose potential arising from other electrified bodies
is Yj , has for components
X“*2 dx ~ Pl£?2>
Y— ^2 dy -~Ql*2’
(D)
r/ t>
So that an electrified body is urged in the direction of the electromotive force with a
force equal to the product of the quantity of free electricity and the electromotive force.
If the electrification of the field arises from the presence of a small electrified body
containing el of free electrity, the only solution of Y l is
— A eJL,
An r
(43)
where r is the distance from the electrified body.
The repulsion between two electrified bodies e„ ea is therefore
d%_ k ej^
2 dr An r 2
(44)
Measurement of Electrical Phenomena by Electrostatic Effects.
(80) The quantities with which we have had to do have been hitherto expressed in
terms of the Electromagnetic System of measurement, which is founded on the mecha-
nical action between currents. The electrostatic system of measurement is founded on
the mechanical action between electrified bodies, and is independent of, and incom-
patible with, the electromagnetic system ; so that the units of the different kinds of
quantity have different values according to the system we adopt, and to pass from the
one system to the other, a reduction of all the quantities is required.
According to the electrostatic system, the repulsion between two small bodies charged
with quantities jj. , % of electricity is
r2 ’
where r is the distance between them.
Let the relation of the two systems be such that one electromagnetic unit of elec-
tricity contains v electrostatic units; then ril=ve1 and fi2=zve2, and this repulsion becomes
** 7?=^ 73T by equation (44) (45)
whence k, the coefficient of “ electric elasticity ” in the medium in which the experi-
ments are made, i. e. common air, is related to v, the number of electrostatic units in one
electromagnetic unit, by the equation
&= 4w\
3 x
MDCCCLXV.
. (46)
492
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
The quantity v may be determined by experiment in several ways. According to the
experiments of MM. Weber and Kohlrausch,
0=310,740,000 metres per second.
(81) It appears from this investigation, that if we assume that the medium which
constitutes the electromagnetic field is, when dielectric, capable of receiving in every
part of it an electric polarization, in which the opposite sides of every element into
which we may conceive the medium divided are oppositely electrified, and if we also
assume that this polarization or electric displacement is proportional to the electro-
motive force which produces or maintains it, then we can show that electrified bodies
in a dielectric medium will act on one another with forces obeying the same laws as are
established by experiment.
The energy, by the expenditure of which electrical attractions and repulsions are pro-
duced, we suppose to be stored up in the dielectric medium which surrounds the electri-
fied bodies, and not on the surface of those bodies themselves, which on our theory
are merely the bounding surfaces of the air or other dielectric in which the true springs
of action are to be sought.
Note on the Attraction of Gravitation.
(82) After tracing to the action of the surrounding medium both the magnetic and
.the electric attractions and repulsions, and finding them to depend on the inverse square
of the distance, we are naturally led to inquire whether the attraction of gravitation,
which follows the same law of the distance, is not also traceable to the action of a
surrounding medium.
Gravitation differs from magnetism and electricity in this ; that the bodies concerned
are all of the same kind, instead of being of opposite signs, like magnetic poles and
electrified bodies, and that the force between these bodies is an attraction and not a
repulsion, as is the case between like electric and magnetic bodies.
The lines of gravitating force near two dense bodies are exactly of the same form as
the lines of magnetic force near two poles of the same name ; but whereas the poles are
repelled, the bodies are attracted. Let E be the intrinsic energy of the field surrounding
two gravitating bodies M,, M2, and let E' be the intrinsic energy of the field surrounding
two magnetic poles m1? m2, equal in numerical value to M,, M2, and let X be the gravi-
tating force acting during the displacement lx, and X' the magnetic force,
X^=SE, X'lx=l E';
now X and X' are equal in numerical value, but of opposite signs ; so that
IE=-IE',
or
E=C — E'
=C-2i(«>+/3‘+/)<iVJ
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD. 49 3
where a, /3, y are the components of magnetic intensity. If It be the resultant gravi-
tating force, and R' the resultant magnetic force at a corresponding part of the field,
R=-R', and a2+/32+y2=R2=R'2.
Hence
E=C-^RW (47)
The intrinsic energy of the field of gravitation must therefore be less wherever there is
a resultant gravitating force.
As energy is essentially positive, it is impossible for any part of space to have nega-
tive intrinsic energy. Hence those parts of space in which there is no resultant force,
such as the points of equilibrium in the space between the different bodies of a system,
and within the substance of each body, must have an intrinsic energy per unit of volume
greater than
where R is the greatest possible value of the intensity of gravitating force in any part of
the universe.
The assumption, therefore, that gravitation arises from the action of the surrounding
medium in the way pointed out, leads to the conclusion that every part of this medium
possesses, when undisturbed, an enormous intrinsic energy, and that the presence of
dense bodies influences the medium so as to diminish this energy wherever there is a
resultant attraction.
As I am unable to understand in what way a medium can possess such properties, I
cannot go any further in this direction in searching for the cause of gravitation.
PART V.— THEORY OF CONDENSERS.
Capacity of a Condenser.
(83) The simplest form of condenser consists of a uniform layer of insulating matter
bounded by two conducting surfaces, and its capacity is measured by the quantity of
electricity on either surface when the difference of potentials is unity.
Let S be the area of either surface, a the thickness of the dielectric, and k its coeffi-
cient of electric elasticity; then on one side of the condenser the potential is 'vIr1, and on
the other side and within its substance
"=]=¥•
(48)
Since ^ and therefore f is zero outside the condenser, the quantity of electricity on its
first surface = — S /*, and on the second -}- S/l The capacity of the condenser is there-
jg
fore in electromagnetic measure.
3x2
494 PEOFESSOE CLEEK MAXWELL ON THE ELECTEOMAGNETIC FIELD.
Specific Capacity of Electric Induction (D).
(84) If the dielectric of the condenser be air, then its capacity in electrostatic mea-
S
sure is ^ (neglecting corrections arising from the conditions to be fulfilled at the
edges). If the dielectric have a capacity whose ratio to that of air is D, then the capa-
DS
city of the condenser will be — •
Atta
Hence D=^a, ..... ■ (49)
where k0 is the value of k in air, which is taken for unity.
Electric Absorption.
(85) When the dielectric of which the condenser is formed is not a perfect insulator,
the phenomena of conduction are combined with those of electric displacement. The
condenser, when left charged, gradually loses its charge, and in some cases, after being
discharged completely, it gradually acquires a new charge of the same sign as the original
charge, and this finally disappears. These phenomena have been described by Professor
Faraday (Experimental Researches, Series XI.) and by Mr. F. Jenkin (Report of Com-
mittee of Board of Trade on Submarine Cables), and may be classed under the name of
“ Electric Absorption.”
(86) We shall take the case of a condenser composed of any number of parallel layers
of different materials. If a constant difference of potentials between its extreme
surfaces is kept up for a sufficient time till a condition of permanent steady flow of
electricity is established, then each bounding surface will have a charge of electricity
depending on the nature of the substances on each side of it. If the extreme surfaces
be now discharged, these internal charges will gradually be dissipated, and a certain
charge may reappear on the extreme surfaces if they are insulated, or, if they are con-
nected by a conductor, a certain quantity of electricity may be urged through the con-
ductor during the reestablishment of equilibrium.
Let the thickness of the several layers of the condenser be ax, a2, &c.
Let the values of k for these layers be respectively k2, k3, and let
ajc2 -\-a2k2 -f &c. =ak, (50)
where k is the “ electric elasticity” of air, and a is the thickness of an equivalent con-
denser of air.
Let the resistances of the layers be respectively r„ r2, &c., and let rx-\-r2- & c. =r be
the resistance of the whole condenser, to a steady current through it per unit of surface.
Let the electric displacement in each layer befi,f2, &c.
Let the electric current in each layer be px,p2, &c.
Let the potential on the first surface be 'P,, and the electricity per unit of surface et.
Let the corresponding quantities at the boundary of the first and second surface be
’Pa and e2, and so on. Then by equations (G) and (H),
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
495
_ n de i _ }
e'~ /*> dt -?1’
«.=/-/»»■ §=^1-^2, [
&c. &c.
But by equations (E) and (F),
'Fa 'F 3 = ajc^^ = —
&c. &c. &c.
(51)
(52)
After the electromotive force has been kept up for a sufficient time the current
becomes the same in each layer, and
q/
jp1=p2=& c. =p = —i
where 'F is the total difference of potentials between the extreme layers. We have then
and
■'P rx
r CiAj’
'l
akj’
&c.
(53)
These are the quantities of electricity on the different surfaces.
(87) Now let the condenser be discharged by connecting the extreme surfaces
through a perfect conductor so that their potentials are instantly rendered equal, then
the electricity on the extreme surfaces will be altered, but that on the internal surfaces
will not have time to escape. The total difference of potentials is now
^ &c. =0, (54)
whence if e\ is what ex becomes at the instant of discharge,
j ¥_r, T —
1 r alk] ak ak
(55)
The instantaneous discharge is therefore or the quantity which would be dis-
charged by a condenser of air of the equivalent thickness a, and it is unaffected by the
want of perfect insulation.
(88) Now let us suppose the connexion between the extreme surfaces broken, and the
condenser left to itself, and let us consider the gradual dissipation of the internal charges.
Let "V be the difference of potential of the extreme surfaces at any time t ; then
^'■=ajcxf, + ajcj, ;+&c.; (56)
dfi
496
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
Hence f^=A.^e , /2= A2<?~ , &c. ; and by referring to the values of e2, &c.,
we find
a r, ¥
1_ r ak'
7" «2a:2 ak
&c. ;
(57)
so that we find for the difference of extreme potentials at any time,
. . (58)
(89) It appears from this result that if all the layers are made of the same sub-
stance, T-' will be zero always. If they are of different substances, the order in which
they are placed is indifferent, and the effect will be the same whether each substance
consists of one layer, or is divided into any number of thin layers and arranged in any
order among thin layers of the other substances. Any substance, therefore, the parts
of which are not mathematically homogeneous, though they may he apparently so, may
exhibit phenomena of absorption. Also, since the order of magnitude of the coefficients
is the same as that of the indices, the value of W can never change sign, but must start
from zero, become positive, and finally disappear.
(90) Let us next consider the total amount of electricity which would pass from the
first surface to the second, if the condenser, after being thoroughly saturated by the
current and then discharged, has its extreme surfaces connected by a conductor of
resistance R. Let p be the current in this conductor ; then, during the discharge,
''¥'=plrl-\-p2r2+&c.=p'R (59)
Integrating with respect to the time, and calling ql, q2, q the quantities of electricity
which traverse the different conductors,
5,17'i+5'2r2+&c.=5,R.
The quantities of electricity on the several surfaces will be
4 — ? — ?i>
02+?.— ?2,
&c. ;
and since at last all these quantities vanish, we find
(60)
?. =0.-?,
?2 =0r,+02— ?;
whence
¥r
ak ’
»b=?( 4+4+&C.)-:
r Va,*, a2k9 /
(61)
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD. 497
a quantity essentially positive ; so that, when the primary electrification is in one direc-
tion, the secondary discharge is always in the same direction as the primary discharge*.
PART VI.— ELECTROMAGNETIC THEORY OF LIGHT.
(91) At the commencement of this paper we made use of the optical hypothesis of
an elastic medium through which the vibrations of light are propagated, in order to
show that we have warrantable grounds for seeking, in the same medium, the cause of
other phenomena as well as those of light. We then examined electromagnetic pheno-
mena, seeking for their explanation in the properties of the field which surrounds the
electrified or magnetic bodies. In this way we arrived at certain equations expressing
certain properties of the electromagnetic field. We now proceed to investigate whether
these properties of that which constitutes the electromagnetic field, deduced from electro-
magnetic phenomena alone, are sufficient to explain the propagation of light through
the same substance.
(92) Let us suppose that a plane wave whose direction cosines are l , m, n is propa-
gated through the field with a velocity V. Then all the electromagnetic functions will
be functions of 7 , , Tr ,
w=lx-\-my-\-nz— Yt.
The equations of Magnetic Force (B), p. 482, will become
dH
dG
-n
dw ’
ujfi=.n
dF
dH
dw
-l
dw ’
dG
dF
7—1
dw
-771
dw
If we multiply these equations respectively by /, m, n, and add, we find
, (62)
which shows that the direction of the magnetization must be in the plane of the wave.
(93) If we combine the equations of Magnetic Force (B) with those of Electric
Currents (C), and put for brevity
rfF rfG rfH
dx'dy' dz
T , d* , d* , d*
J, and S+^s+^i=V
4W'=|-V’F,
4W=|-vg,
(63)
(64)
* Since this paper was communicated to the Royal Society, I have seen a paper by M. Gaugain in the Annales
de Chimie for 1864, in which he has deduced the phenomena of electric absorption and secondary discharge
from the theory of compound condensers.
498 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
If the medium in the field is a perfect dielectric there is no true conduction, and the
currents^', q', r' are only variations in the electric displacement, or, by the equations of
Total Currents (A),
(65)
n'-f
q'=f,
* dt
, dh
V~Jt
But these electric displacements are caused by electromotive forces, and by the equations
of Electric Elasticity (E),
P =Jcf\ Q^Jcg, R =kh (66)
These electromotive forces are due to the variations either of the electromagnetic or
the electrostatic functions, as there is no motion of conductors in the field ; so that the
equations of electromotive force (D) are
dF_d^
dt dx ’
dG_cW
dt dy
rfH dW
K~ “ dt~ dz ‘
(67)
(94) Combining these equations, we obtain the following : —
KS-vaF)+4'K?+S)=°’
i(|-VG)+V(-?+^)=0, •
*(§-V*H)+4^+S) = 0.
. . (68)
If we differentiate the third of these equations with respect to y, and the second with
respect to z, and subtract, J and T- disappear, and by remembering the equations (B) of
magnetic force, the results may be written
&V2/aa = 4 iryj pa,
d 2
A;V>/3=4^^2^/3,
d 2
ArV>y = 4*-^^py.
(69)
(95) If we assume that a, (3, y are functions of lx-\-my-\-nz — Vt=w, the first equa-
tion becomes
7 d 2a
k(*dw*
(70)
v=±V^‘ <*>
The other equations give the same value forV, so that the wave is prqpagated in either
direction with a velocity V.
PEOFESSOE CLEEK MAXWELL OX THE ELECTEOMAGNETIC FIELD.
499
This wave consists entirely of magnetic disturbances, the direction of magnetization
being in the plane of the wave. No magnetic disturbance whose direction of magneti-
zation is not in the plane of the wave can be propagated as a plane wave at all.
Hence magnetic disturbances propagated through the electromagnetic field agree with
light in this, that the disturbance at any point is transverse to the direction of propaga-
tion, and such waves may have all the properties of polarized light.
(96) The only medium in which experiments have been made to determine the value
of k is air, in which ^=1, and therefore, by equation (46),
V=». (72)
By the electromagnetic experiments of MM. Weber and Kohlrausch*,
v= 310,740,000 metres per second
is the number of electrostatic units in one electromagnetic unit of electricity, and this,
according to our result, should be equal to the velocity of light in air or vacuum.
The velocity of light in air, by M. Fizeau’s f experiments, is
V=314,858,000;
according to the more accurate experiments of M. Foucault J,
V=298,000,000.
The velocity of light in the space surrounding the earth, deduced from the coefficient
of aberration and the received value of the radius of the earth’s orbit, is
V= 308,000,000.
(97) Hence the velocity of light deduced from experiment agrees sufficiently well
with the value of v deduced from the only set of experiments we as yet possess. The
value of v was determined by measuring the electromotive force with which a condenser
of known capacity was charged, and then discharging the condenser through a galvano-
meter, so as to measure the quantity of electricity in it in electromagnetic measure.
The only use made of light in the experiment was to see the instruments. The value
of V found by M. Foucault was obtained by determining the angle through which a
revolving mirror turned, while the light reflected from it went and returned along a
measured course. No use whatever was made of electricity or magnetism.
The agreement of the results seems to show that light and magnetism are affections
of the same substance, and that light is an electromagnetic disturbance propagated
through the field according to electromagnetic laws.
(98) Let us now go back upon the equations in (94), in which the quantities J and
F occur, to see whether any other kind of disturbance can be propagated through
the medium depending on these quantities which disappeared from the final equations.
* Leipzig Transactions, vol. v. (1857), p. 260, or Poggekdorff’s * Annalen,’ Aug. 1856, p. 10.
f Comptes Eendus, vol. xxix. (1849), p. 90. J Ibid. vol. lv. (1862), pp. 501, 792.
MDCCCLXV. 3 Y
500
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
If we determine ^ from the equation
(73)
and F', G', H' from the equations
F'=F-^, G'=G-^, H'=H-^, .... (74)
dx dy dz x '
then
dF' , dG' , tfH' _
7i + W + ^!=0’ (/5)
and the equations in (94) become of the form
*VT'=4^ +J-it (y+I)) (76)
Differentiating the three equations with respect to x, y, and z , and adding, we find that
Y=-f +?(*>■?>*)> (77)
and that £V2F' — 4^ .
^V2G'=4^^,P (78)
W2H'=4^£J^, !
1 dr2 j
Hence the disturbances indicated by F', G, H' are propagated with the velocity
V = a / — through the field ; and since
V 47TjU.
dF' dG' <ZH'
dx dy dx ’
the resultant of these disturbances is in the plane of the wave.
(99) The remaining part of the total disturbances F, G, H being the part depending
on %, is subject to no condition except that expressed in the equation
W d*x _0
dt + dt 2 “ U-
If we perform the operation V2 on this equation, it becomes
ke= ^-Jc\72p(x, y, z) (79)
Since the medium is a perfect insulator, e, the free electricity, is immoveable, and
therefore ^ is a function of x, y, z, and the value of J is either constant or zero, or
uniformly increasing or diminishing with the time; so that no disturbance depending
on J can be propagated as a wave.
(100) The equations of the electromagnetic field, deduced from purely experimental
evidence, show that transversal vibrations only can be propagated. If we were to go
beyond our experimental knowledge and to assign a definite density to a substance which
PEOFESSOE CLEEK MAXWELL ON THE ELECTEOMAGXET1C FIELD.
501
we should call the electric fluid, and select either vitreous or resinous electricity as the
representative of that fluid, then we might have normal vibrations propagated with a
velocity depending on this density. We have, however, no evidence as to the density of
electricity, as we do not even know whether to consider vitreous electricity as a sub-
stance or as the absence of a substance.
Hence electromagnetic science leads to exactly the same conclusions as optical science
with respect to the direction of the disturbances which can be propagated through the
field; both affirm the propagation of transverse vibrations, and both give the same velocity
of propagation. On the other hand, both sciences are at a loss when called on to affirm
or deny the existence of normal vibrations.
'Relation between the Index of Refraction and the Electromagnetic Character of the
substance.
(101) The velocity of light in a medium, according to the Undulatory Theory, is
where i is the index of refraction and V0 is the velocity in vacuum. The velocity,
according to the Electromagnetic Theory, is
where, by equations (49) and (71), k=^k0, and k0=iirWl.
(80)
Hence
D =
or the Specific Inductive Capacity is equal to the square of the index of refraction
divided by the coefficient of magnetic induction.
Propagation of Electromagnetic Disturbances in a Crystallized Medium.
(102) Let us now calculate the conditions of propagation of a plane wave in a
medium for which the values of k and p are different in different directions. As we
do not propose to give a complete investigation of the question in the present imperfect
state of the theory as extended to disturbances of short period, we shall assume that the
axes of magnetic induction coincide in direction with those of electric elasticity.
(103) Let the values of the magnetic coefficient for the three axes be X, v, then
the equations of magnetic force (B) become
^ M dy dz ’
0 d¥ dH
^P = -T-— -j- 1
«(H dG
'AP— dz ~ dx
(81)
dG d¥_
dx~ dy'
3 Y 2
502 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
The equations of electric currents (C) remain as before.
The equations of electric elasticity (E) will be
P = W/, |
Q=4 l (82)
R=4 7rc2h, J
where 4 4w52, and 4 tt(? are the values of k for the axes of x, y, z.
Combining these equations with (A) and (D), we get equations of the form
(104) If l , to, n are the direction-cosines of the wave, and V its velocity, and if
lx-\-my-\-nz— Vt=w, (84)
then F, G, H, and Y will be functions of w ; and if we put F', G', H', Y' for the second
differentials of these quantities with respect to w , the equations will be
(v!-b,(~+^))f,+ ^G'+^H'-?V'P'=0,
(^-'!C-+i))ff+7i’+xG'-»w=«'
If we now put
(85)
V4 — "V"2 -f- c2v) -f- rnvlyj(c1v -f- tt2X) -j- vikv[dk~k -f- 1> "^)|’
we shall find
F'V2U-ZT"VU=0,
with two similar equations for G' and H'. Hence either
. (86)
. (87)
Y = 0, (88)
U=0, (89)
or
VF' = ZT", YG'=to^ and YB.'=nY' (90)
The third supposition indicates that the resultant of F', G', H' is in the direction
normal to the plane of the wave ; but the equations do not indicate that such a disturb-
ance, if possible, could be propagated, as we have no other relation between M'' and
F', G', H'.
The solution Y=0 refers to a case in which there is no propagation.
The solution U = 0 gives two values for Y2 corresponding to values of F'. G', H', which
PEOFESSOE CLEEK MAXWELL ON THE ELECTEOMAGNETIC FIELD.
503
are given by the equations
.'f+”G'+“H'=0, (91)
^(5>-A)+^(A-^)+^(aV-5»=0, (92)
(105) The velocities along the axes are as
Direction of propagation .
Direction of the electric displacements -j
Now we know that in each principal plane of a crystal the ray polarized in that
plane obeys the ordinary law of refraction, and therefore its velocity is the same in
whatever direction in that plane it is propagated.
If polarized light consists of electromagnetic disturbances in which the electric dis-
placement is in the plane of polarization, then
a2=J2=c2 (93)
If, on the contrary, the electric displacements are perpendicular to the plane of pola-
rization,
X=p=v (94)
We know, from the magnetic experiments of Faraday, Plucker, & c., that in many
crystals a, v are unequal.
The experiments of Knoblauch * on electric induction through crystals seem to show
that a, b and c, may be different.
The inequality, however, of X, p, v is so small that great magnetic forces are required
to indicate their difference, and the differences do not seem of sufficient magnitude to
account for the double refraction of the crystals.
On the other hand, experiments on electric induction are liable to error on account
of minute flaws, or portions of conducting matter in the crystal.
Further experiments on the magnetic and dielectric properties of crystals are required
before we can decide whether the relation of these bodies to magnetic and electric
forces is the same, when these forces are permanent as when they are alternating with
the rapidity of the vibrations of light.
* Philosophical Magazine, 1852.
follows : —
X
y
z
d 2
d 2
X
—
—
V
b2
b 2
y
V
A
c2
c2
z
A
504
PROFESSOR OLEEK MAXWELL ON THE ELECTROMAGNETIC FIELD.
Relation between Electric Resistance and Transparency.
(106) If the medium, instead of being a perfect insulator, is a conductor whose resist-
ance per unit of volume is g>, then there will be not only electric displacements, but true
currents of conduction in which electrical energy is transformed into heat, and the undu-
lation is thereby weakened. To determine the coefficient of absorption, let us investi-
gate the propagation along the axis of x of the transverse disturbance G.
By the former equations
^ = -4 Tyj(q')
d* G . /I d^G 1 rfG\ , .-p,. , /nc:\
^ = + 4^ w -- by(E)and(F) (95)
If G is of the form
G=e~p* cos (qx-\-nt), (96)
we find that
f97)
g q g i v
where V is the velocity of light in air, and i is the index of refraction. The proportion
of incident light transmitted through the thickness x is
(98)
Let R be the resistance in electromagnetic measure of a plate of the substance whose
thickness is x, breadth b, and length l, then
(107) Most transparent solid bodies are good insulators, whereas all good conductors
are very opaque.
Electrolytes allow a current to pass easily and yet are often very transparent. We
may suppose, however, that in the rapidly alternating vibrations of light, the electro-
motive forces act for so short a time that they are unable to effect a complete separation
between the particles in combination, so that when the force is reversed the particles
oscillate into their former position without loss of energy.
Gold, silver, and platinum are good conductors, and yet when reduced to sufficiently
thin plates they allow light to pass through them. If the resistance of gold is the same
for electromotive forces of short period as for those with which we make experiments,
the amount of light which passes through a piece of gold-leaf, of which the resistance
was determined by Mr. C. Hockin, would be only 10-50 of the incident light, a totally
imperceptible quantity. I find that between and x^o“o °f green light gets through
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
505
such gold-leaf. Much of this is transmitted through holes and cracks; there is enough,
however, transmitted through the gold itself to give a strong green hue to the
transmitted light. This result cannot be reconciled with the electromagnetic theory
of light, unless we suppose that there is less loss of energy when the electromotive forces
are reversed with the rapidity of the vibrations of light than when they act for sensible
times, as in our experiments.
Absolute Values of the Electromotive and Magnetic Forces called into jplay in the
Propagation of Light.
(108) If the equation of propagation of light is
F=Acos ^(z-Vt),
the electromotive force will be
P = — A y V sin y (z— V*) ;
and the energy per unit of volume will be
P2
87rjxV2’
where P represents the greatest value of the electromotive force. Half of this consists
of magnetic and half of electric energy.
The energy passing through a unit of area is
so that
P =V8^VW,
where V is the velocity of light, and W is the energy communicated to unit of area by
the light in a second.
According to Pouillet’s data, as calculated by Professor W. Thomson*, the mecha-
nical value of direct sunlight at the Earth is
83-4 foot-pounds per second per square foot.
This gives the maximum value of P in direct sunlight at the Earth’s distance from the Sun,
P=60,000,000,
or about 600 Daniell’s cells per metre.
At the Sun’s surface the value of P would be about
13,000 Daniell’s cells per metre.
At the Earth the maximum magnetic force would be T93f.
At the Sun it would be 4T3.
These electromotive and magnetic forces must be conceived to be reversed twice in
every vibration of light ; that is, more than a thousand million million times in a second.
Transactions of the Royal Society of Edinburgh, 1854 (“Mechanical Energies of the Solar System”).
The horizontal magnetic force at Kew is about l-76 in metrical units.
506
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
PART VII.— CALCULATION OF THE COEFFICIENTS OF ELECTROMAGNETIC INDUCTION.
General Methods.
(109) The electromagnetic relations between two conducting circuits, A and B,
depend upon a function M of their form and relative position, as has been already
shown.
M may be calculated in several different ways, which must of course all lead to the
same result.
First Method. M is the electromagnetic momentum of the circuit B when A carries
a unit current, or , & dy &
M=J(F5?+GS+H*i)*>
where F, G, H are the components of electromagnetic momentnm due to a unit current
in A, and ds' is an element of length of B, and the integration is performed round the
circuit of B.
To find F, G, H, we observe that by (B) and (C)
d°F , d2F , d2F .
with corresponding equations for G and H, p', <[, and F being the components of the
current in A.
Now if we consider only a single element ds of A, we shall have
2 '=5*i
and the solution of the equation gives
where § is the distance of any point from ds. Hence
HJ?(
dx dx dy dy dz dz\ , 7 ,
dj+dsdP+dsdP)dsds
= |j ^cos 6dsdd.
where 0 is the angle between the directions of the two elements ds, ds', and § is the
distance between them, and the integration is performed round both circuits.
In this method we confine our attention during integration to the two linear circuits
alone.
(110) Second Method. M is the number of lines of magnetic force which pass
through the circuit B when A carries a unit current, or
M = 'Zfacil+pftm -\-^yn)dSl,
where pa, py are the components of magnetic induction due to unit current in A,
PROFESSOR CLERK MAXWELL OX THE ELECTROMAGNETIC FIELD. 507
S' is a surface bounded by the current B, and l, m, n are the direction-cosines of the
normal to the surface, the integration being extended over the surface.
We may express this in the form
M=jM-2^sin 0 sin 0 sin (pdS'ds,
where d& is an element of the surface bounded by B, ds is an element of the circuit A,
g is the distance between them, 0 and 0 are the angles between g and ds and between
g and the normal to dS' respectively, and <p is the angle between the planes in which
0 and 0 are measured. The integration is performed round the circuit A and over the
surface bounded by B.
This method is most convenient in the case of circuits lying in one plane, in which
case sin 0=1, and sin<p=l.
111. Third Method. M is that part of the intrinsic magnetic energy of the whole
field which depends on the product of the currents in the two circuits, each current
being unity.
Let a, /3, y be the components of magnetic intensity at any point due to the first
circuit, a!, (31, y' the same for the second circuit; then the intrinsic energy of the
element of volume dV of the field is
£((«+«?+(|3+/ 3')’+(7+r')!)'iV.
The part which depends on the product of the currents is
f(a«'+/3/3 '+yy’)dV.
4 7T
Hence if we know the magnetic intensities I and I' due to unit current in each circuit,
we may obtain M by integrating
J^lul T cos m
4 7T r
over all space, where 0 is the angle between the directions of I and I'.
Application to a Coil.
(112) To find the coefficient (M) of mutual induction between two circular linear
conductors in parallel planes, the distance between the curves being everywhere the same,
and small compared with the radius of either.
If r be the distance between the curves, and a the radius of either, then when r is
very small compared with a, we find by the second method, as a first approximation,
M=Lra(loge^— 2V
To approximate more closely to the value of M, let a and ax be the radii of the circles,
and b the distance between their planes ; then
r2=(a— «,)2+§2.
3 z
MDCCCLXV.
508
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
We obtain M by considering the following conditions:—
1st. M must fulfil the differential equation
dm dm l <m
■ da 2 + dtf +0 da ~ U’
This equation being true for any magnetic field symmetrical with respect to the common
axis of the circles, cannot of itself lead to the determination of M as a function of a ,
and b. We therefore make use of other conditions.
2ndly. The value of M must remain the same when a and ax are exchanged.
3rdly. The first two terms of M must be the same as those given above.
M may thus be expanded in the following series : —
8 r ( ~2 a ' 16 dz 32 a3 j
— irah 4 1 1 b2-3{a-a*)_ 1 (6b°~~ (a-a^ia-a,) , » \
\ 2 a ' 16 a2 48 a3 j
(113) We may apply this result to find the coefficient of self-induction (L) of a circular
coil of wire whose section is small compared with the radius of the circle.
Let the section of the coil be a rectangle, the breadth in the plane of the circle being
c, and the depth perpendicular to the plane of the circle being b.
Let the mean radius of the coil be a, and the number of windings n ; then we find,
by integrating, ^
L=F?J JjJ M(^ %'y')dx dy dx' dy\
where M [xy cdy') means the value of M for the two windings whose coordinates are xy
and x'y] respectively ; and the integration is performed first with respect to x and y over
the rectangular section, and then with respect to x' and y' over the same space.
L = Ann2 a jloge— + ^ — ^ cot 2 0 — ^ cos 2 0 — ^ cot2 0 log cos 0 — ^ tan2 0 log sin 6
+-
logy(2 sin2^+l) + 3-45+27-475 cos20-3-2(|-^
sin30 lcos40,
log cos 6
cosfl 1 5 sm2S &
13 sin4 9 . .) . D
+T^logsm7+&e-
Here a= mean radius of the coil.
„ t— diagonal of the rectangular section =\Z^2+c2.
„ 0= angle between r and the plane of the circle.
„ n= number of windings.
The logarithms are Napierian, and the angles are in circular measure.
In the experiments made by the Committee of the British Association for deter-
mining a standard of Electrical Resistance, a double coil was used, consisting of two
nearly equal coils of rectangular section, placed parallel to each other, with a small
interval between them.
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
509
The value of L for this coil was found in the following way.
The value of L was calculated by the preceding formula for six different cases, in
which the rectangular section considered has always the same breadth, while the depth
was
A, B, C, A-j-B, B+C, A+B+C,
and n=l in each case.
Calling the results
L(A), L(B), L(C), &c.,
we calculate the coefficient of mutual induction M(AC) of the two coils thus,
2ACM(AC)=(A+B+C)2L(A+B+C)-(A+B)2L(A+B)-(B+C)2L(B+C)+B2L(B).
Then if nx is the number of windings in the coil A and n2 in the coil B, the coefficient
of self-induction of the two coils together is
L=ft2L(A)+2rc,%L(AC)+w2L(B).
(114) These values of L are calculated on the supposition that the windings of the
wire are evenly distributed so as to fill up exactly the whole section. This, however, is
not the case, as the wire is generally circular and covered with insulating material.
Hence the current in the wire is more concentrated than it would have been if it had
been distributed uniformly over the section, and the currents in the neighbouring wires
do not act on it exactly as such a uniform current would do.
The corrections arising from these considerations may be expressed as numerical
quantities, by which we must multiply the length of the wire, and they are the same
whatever be the form of the coil.
Let the distance between each wire and the next, on the supposition that they are
arranged in square order, be D, and let the diameter of the wire be d, then the correc-
tion for diameter of wire is
The correction for the eight nearest wires is
+0-0236.
For the sixteen in the next row
+0-00083.
These corrections being multiplied by the length of wire and added to the former
result, give the true value of L, considered as the measure of the potential of the coil
on itself for unit current in the wire when that current has been established for some
time, and is uniformly distributed through the section of the wire.
(115) But at the commencement of a current and during its variation the current is
not uniform throughout the section of the wire, because the inductive action between
different portions of the current tends to make the current stronger at one part of the
section than at another. When a uniform electromotive force P arising from any cause
510 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
acts on a cylindrical wire of specific resistance g>, we have
-n d¥
?i=?—dr
where F is got from the equation
d12 F 1 d¥
dr2 ' r dr
= -4 vp-p,
r being the distance from the axis of the cylinder.
Let one term of the value of F be of the form T rn, where T is a function of the time,
then the term of p which produced it is of the form
— -t— n?Trn-2.
47 T[&
Hence if we write
*=t+7 (-p+f r+TTir** wr‘+ **
n~-
' dt ' " r
j2 1 ds T
dt2‘
r4— &c.
q I I2 . 22 dtS
point is
CfP \ 7 , 1 rp [X.7T dT /A2 1 d2T
Jli-^;<B=i:T+7 ^ + ™ wr + &c-
The total counter current of self-induction at any point is
At2 1 d*T
from t— 0 to t — co .
When t= 0, j>=0, =P, =0, &c.
When t=oo , w = s
• =0. (S),
= 0, &c.
a' /P \ 7 lm „ 1 LOT2 dT , f*27T3 1 fi?2T -
25r(j -p)rdrdt= -W+ 2Y~dir +lr TVFTs &c-
from t=0 to =oo .
When £=0, p= 0 throughout the section, .\ =P, = 0, &c-
When t= co , p=0 throughout \ ) = 05 =0, &c.
Also if l be the length of the wire, and R its resistance,
k=4;
and if C be the current when established in the wire, C= -yp
The total counter current may be written
B(T--T.)-|4c=-^by§(35).
PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD. 511
Now if the current instead of being variable from the centre to the circumference of
the section of the wire had been the same throughout, the value of F would have been
F=T+W(l-Q,
where y is the current in the wire at any instant, and the total countercurrent would
have been
Hence
ff
IdF l
-2 %rdr—
§
a„.„_K(T.-iy-!(.|EO=—
L'C
!-> say-
L=L'-fcfcZ,
or the value of L which must be used in calculating the self-induction of a wire for
variable currents is less than that which is deduced from the supposition of the current
being constant throughout the section of the wire by +/+ where l is the length of the
wire, and [Jj is the coefficient of magnetic induction for the substance of the wire.
(116) The dimensions of the coil used by the Committee of the British Association
in their experiments at King’s College in 1864 were as follows : —
metre.
Mean radius ....... =«=T58194
Depth of each coil =§ = -01608
Breadth of each coil .... = c = -01841
Distance between the coils . . . =-02010
Number of windings .... ^=313
Diameter of wire =-00126
The value of L derived from the first term of the expression is 437440 metres.
The correction depending on the radius not being infinitely great compared with the
section of the coil as found from the second term is — 7345 metres.
The correction depending on the diameter of the wire is 1 .
. \ & . + -44997
per unit oi length J
Correction of eight neighbouring wires +-0236
For sixteen wires next to these +-0008
Correction for variation of current in different parts of section — -2500
Total correction per unit of length -22437
Length 311-236 metres.
Sum of corrections of this kind 70 „
Final value of L by calculation 430165 „
This value of L was employed in reducing the observations, according to the method
explained in the Report of the Committee*. The correction depending on L varies
as the square of the velocity. The results of sixteen experiments to which this correc-
tion had been applied, and in which the velocity varied from 100 revolutions in
seventeen seconds to 100 in seventy-seven seconds, were compared by the method of
* British Association Reports, 1863, p. 169.
512 PROFESSOR CLERK MAXWELL ON THE ELECTROMAGNETIC FIELD.
least squares to determine what further correction depending on the square of the
velocity should be applied to make the outstanding errors a minimum.
The result of this examination showed that the calculated value of L should be
multiplied by 1-0618 to obtain the value of L, which would give the most consistent
results.
We have therefore L by calculation 430165 metres.
Probable value of L by method of least squares 456748 „
Eesult of rough experiment with the Electric Balance (see § 46) 410000 „
The value of L calculated from the dimensions of the coil is probably much more
accurate than either of the other determinations.
C 513 ]
IX. On the Ernbryogeny of Antedon rosaceus, LincJc (Comatula rosacea of Lamarck).
By Professor Wyville Thomson, LL.D., F.B.S.E., M.B.I.A., F.G.S., &c. Com-
municated by Thomas Henry Huxley, F.B.S.
Received December 29, 1862, — Read February 5, 1863*.
In the year 1827 Mr. J. V. Thomson, Deputy Inspector-General of Military Hospitals,
described and figured what he believed to be a new recent Crinoid, under the name of
Pentacrinus Europceus ; and in June 1835 communicated to this Society a “Memoir on
the Star-fish of the genus Comatula , demonstrative of the Pentacrinus Europceus being
the young of our indigenous species.” In this memoir the author describes and figures
a series of Pentacrinus Europeans from its earliest stage, in which it is represented as
“ an attached ovum in the form of a flattened oval disk, by which it is permanently fixed
to the point selected, giving exit to an obscurely jointed stem ending in a club-shaped
head”; to its most perfect attached condition, in which the head is compared with, and
found closely to resemble the youngest free Antedon taken with the dredge.
The period of the disappearance of the pentacrinoid larvae on the oar-weed exactly
corresponds with that of the appearance of the most minute free Antedons in the water.
Mr. Thomson’s observations were conclusive. I am not aware that they have hitherto
been repeated in detail on the European species, but the “ pentacrinoid ” stage of Ante-
don has ever since been the frequent and familiar prize of the dredger, the wonderful
beauty and gracefulness of its form and movements, and its singular relations to the
Echinoderm inhabitants of modern and of primaeval seas, rendering it an object of ever
recurring admiration and interest.
The remarkable discoveries of Professors Sars and Johannes Muller on the meta-
morphoses of the embryo and its appendages in other Echinoderm orders rendered it
probable that the germ of Antedon might pass through some earlier transitional stage
before assuming the fixed pentacrinoid form.
Dr. W. Busch undertook this investigation, and for this purpose he visited Orkney in
J uly 1849, and procured a supply of specimens in Kirkwall Bay. As those of Dr. Busch
are the only recorded observations on the early stages in the embryology of the Crinoids,
I shall briefly abstract his results published in Muller’s ‘ Archiv,’ 1849, and more fully
* Subsequently to tbe reading of this paper it was arranged that the author should take up a somewhat later
stage in the development, which he had at first intended to leave to Dr. Carpenter. The paper was accordingly
returned to him that it might receive the necessary additions ; but no alteration of importance has been made
in the description of the earlier developmental stages, which formed the subject of the memoir presented to the
Royal Society.
4 A
MDCCCLXV.
514
PROFESS OR W. THOMSON ON THE EMBRYOGENY OE ANTEDON
in his own ‘ Beobachtungen iiber Anatomie und Entwickelung einiger wirbellosen
Seethiere’ (Berlin, 1851).
The author alludes to the position of the ovary in Antedon , and to the peculiar way
in which the impregnated ova remain hanging in bunches from the ovarian aperture.
He describes the formation from the segmented yelk-mass of a uniformly ciliated club-
shaped embryo, which escapes from the vitelline membrane and swims freely in the
water (Beobachtungen, &c., pi. 13. fig. 13). During the next four-and-twenty hours a
bunch of long cilia appears on the narrower anterior extremity, and near it, on the side
of the embryo which is turned downwards in a state of rest, a small round opening which
he regards as the provisional larval mouth. Three slightly elevated ridges now gird the
body transversely at equal distances (op. tit. pi. 13. fig. 14), and gradually become clothed
with long cilia, the smaller cilia disappearing from the intervening spaces. The inte-
gument between the first and third ciliated ring becomes inverted into a large oval
depression, a fourth ciliated band appears near the posterior extremity of the embryo,
and a few delicate areolated calcareous plates are developed within the integument.
The embryo now becomes slightly curved, the large oval opening which the author
regards as the excretory orifice becomes more distinct in the centre of the ventral surface,
and the embryo attains its most perfect larval form (pi. 14. figs. 1 & 2). The form of
the larva now rapidly alters ; on the ninth day (pi. 14. fig. 3) the posterior extremity has
become much enlarged and invested with a thick gelatinous integument. This distended
extremity becomes slightly lobed, the anterior bunch of cilia and the posterior ciliated
bands disappear, the mouth and anus become indistinct (pi. 14. fig. 5), and at length
(pi. 14. fig. 6) a row of four delicate tubes bearing pinnules appears along either side of
the larva, the rudiments of the arms of the Crinoid. Dr. Busch was unable to pursue
his researches further. In many points his observations are inconsistent with those
which I have repeated during the last three years with great care, and I believe that
he has misconceived the nature and relations of the organs of the larval embryo. Dr.
Busch’s account of the first appearance of the pentacrinoid form is certainly contrary to
my experience ; I have been led, however, by inconsistencies in my own observations
upon different broods in different seasons, to believe that the mode of development may
to a certain extent vary with circumstances. I find, for instance, that when the ova are
liberally supplied with fresh sea-water and placed in a warm temperature, the later
stages of larval growth are, as it were, hurried over ; so that the free larva scarcely
attains its perfect form before being distorted by the growing crinoid. In other
instances, in colder seasons and in a less favourable medium, the larva reaches a
much higher degree of independent development, and retains for a longer period the
larval form.
In 1859 I communicated to this Society a short notice (Proc. Boyal Society, vol. ix.
p. 600) of the earlier stages in the development of Antedon. My observations were made
upon one or two broods of Antedon in a single season. I had an opportunity at that
time of tracing carefully the earliest phases in the development of the pseudembryo, but
EOSACEUS, LINCK (COMATULA EOSACEA OE LAMAECK).
515
subsequent observations have led me to believe that in some of the later stages the young
of Antedon were confounded with those of a Turbellarian, which resembled them closely,
and which during that season accompanied them in great numbers. These earlier obser-
vations were imperfect and hurried in consequence of the difficulty which I then expe-
rienced in rearing the young, of their extreme delicacy, and of the rapidity with which
they passed through their developmental steps. These difficulties have since been to a
certain extent overcome by the frequent repetition of the observations, and by due regu-
lation of the temperature of the tanks and of the supply of food and water.
M. Dujardix has figured* with great accuracy, but without any description, an early
stage in the development of the pentacrinoid young of Antedon Mediterraneus, Lam.,
which he observed at Toulon in May 1835. The figure represents the oral valves par-
tially open, with a group of tubular tentacles protruded from the cup. It is highly
characteristic.
On the 16th of February, 1863, Professor Allmax communicated to the Royal Society
of Edinburghf a paper “ On aPrebrachial stage in the development of Comatula.” The
author procured a single specimen of the stage represented by Dujardix, and in Plate
XXVI. of the present memoir, among the refuse of a dredging boat on the coast of South
Devon. Dr. Allmax describes this minute Crinoid as consisting of a body and a stem ;
the body formed of a calyx covered by a pyramidal roof. The calyx is composed of five
large separate plates. Between the lower edges of these plates and the summit of the
stem, there is a. narrow zone, in which “ no distinct indications of a composition out of
separate plates can be detected.” Between the upper angles of every two contiguous
plates there may, with some care, be made out a minute intercalated plate. The pyra-
midal roof which closes the cup is composed of five large triangular plates, each sup-
ported by its base upon the upper edge of one of the large plates of the calyx, and with
the small intercalated plates encroaching upon its basal angles. Long flexible append-
ages or cirri rise out of the calyx, and in the expanded state of the animal, are thrown
out between the edges of the five diverging plates of the roof. Dr. Allmax counted
fourteen of these appendages, but could not determine their exact number. “They
appear to be cylindrical with a canal occupying their axis ; as far as they can be traced
backwards they are seen to be furnished with two opposite rows of rigid setae or fine
blunt spines. Between every two opposite setae a transverse line may be seen stretching
across the cirrus, and indicating its division into transverse segments.” The author
never succeeded in tracing these appendages to their origin. Besides these long exten-
sile cirri, there is also an inner circle of short apparently non-extensile appendages.
It was only occasionally that the author succeeded in getting a glimpse of these. “They
appear to constitute a circle of slightly curved rods or narrow plates probably five in
number, which arch over the centre and are provided along their length with two
opposite rows of little tooth-like spines. They seem to be articulated to the upper or
* Suites a Buffon. Zoophytes Echinodermes, par M. E. Dujakdin et par M. E. Htjpe. Paris, 1862.
t Transactions of the Eoyal Society of Edinburgh, vol. zxiii.
4 a 2
516
PROFESSOR W. THOMSON ON THE EMBRYOGENY OF ANTEDON
ventral side of the calyx by their base, and may be seen in a constant motion, which
consists in a sudden inclination upon their base towards the centre, followed immediately
by a resumption of their more erect attitude.” The interior of the calyx is occupied by
a reddish-brown visceral mass, obscurely visible through the walls. The author did not
succeed in getting a view of the mouth, and detected no anal aperture. Dr. Allman
accurately describes the general structure of the stem ( loc . tit. p. 243) ; he conceives,
however, that “ the multiplication of the segments of the stem seems to take place
by the division of the pre-existing ones, and this division seems indicated by the
transverse ridges, which in several of the segments may be seen running round the
centre.”
A detailed description of the developmental stage which forms the subject of Dr.
Allman’s communication will be found at pp. 525 & 526 of the present memoir. It
is unfortunate that so able an observer had not an opportunity of making himself
fully acquainted with this interesting form by the study of a sufficient number of
specimens.
In 1856 Professor Sars communicated to the Seventh Meeting of the Scandinavian
Association a most interesting paper on the Pentacrinoid stage of Antedon Sarsii (Duben
and Koren). The only specimen observed was dredged on the 14th of March with
Halicliondria ventilahrum , from a depth of 50 fathoms near Bergen. It was in every
respect a fully developed Antedon , from the centre of whose centro-dorsal plate proceeded
a long thin cylindrical articulated stem attached inferiorly to the sponge. The disk with
its central mouth, the long, cylindrical, excentric anal tube, the radial grooves, the ten
arms with their characteristic articulations and syzygies, the pinnules with their tentacles,
the rows of red-brown spots on the margins of the grooves on the arms and pinnules,
and the dorsal cirri, were completely developed as in the adult form. All the arms were
unfortunately broken, the portions left bore nine to ten pairs of pinnules. Six of these
were of the ordinary form ; the three or four proximal pairs, which alternated less regu-
larly, were setaceous, destitute of tentacles and pigment spots, the innermost pair longer
than the others, as in the adult ; all the pinnules were attenuated, the generative element
being as yet undeveloped. The dorsal cirri, twenty to thirty in number, were thickly set
round the circumference of the centro-dorsal plate. They were fully formed, and the
joints and terminal claws had the form characteristic of A. Sarsii. The stem was 20
millimetres in length, and consisted of thirty-one joints ; but as it was broken from its place
of attachment, some of the inferior joints may have been lost. The two or three lowermost
joints preserved became shorter towards the base, and the upper joints towards the
attachment of the stem to the centro-dorsal plate decreased likewise in length ; the
second joint was about half the length of the third, and the first only half that of the
second; but the first joint was dilated upwards to its insertion. The middle joints of
the stem are three to three and a half times longer than wide, and are all dice-box
shaped like the joints of the dorsal cirri of the species.
From this observation it would appear that the development of A. Sarsii is continued
ROSACETTS, LIXCK (COMATULA ROSACEA OF LAMARCK).
517
to a much later period in the pedunculated condition than that of A. rosaceus; the dis-
engagement of the latter species from its stem constantly occurs between the middle of
August and the middle of September. The capture of the specimen described by Sars
in March would seem to indicate that the development of the Pentacrinoid of A. Sarsii
extends over nearly a year.
The early portion of the history of the development of Antedon described in the fol-
lowing pages divides itself naturally into two stages.
The Echinoderms present in the most marked degree a peculiarity which seems to be
only imperfectly indicated in the other invertebrate subkingdoms. This peculiarity
consists in the successive development from a single egg, of two organisms, each appa-
rently presenting all the essential characters of a perfect animal. These two beings
seem to ditfer from one another entirely in plan of structure. The first, derived directly
from the germ-mass, would appear at first sight to homologate with some of the lower
forms of the Annulosa ; the second, subsequently produced within or in close organic
connexion with the first, is the true Echinoderm. The extreme form of this singular
cycle, in which the development of a provisional zooid as a separate, independent, living
organism, is carried to its full extent, is by no means constant throughout the whole
subkingdom, although its existence has been established for all the recent orders. In
each order it appears to be exceptional, and in certain cases it is known to be carried
to its most abnormal degree in one species, while in a closely allied species of the
same genus the mode of reproduction differs but slightly from the ordinary inver-
tebrate type.
To avoid ambiguity in the discussion of such singular relations, I believe it is necessary
to introduce certain new terms. For an organism which possesses all the apparent cha-
racters of a distinct animal, which is developed from the germ-mass, and which maintains
a separate existence before the appearance of the embryo, I would propose the term
pseudembryo ; and for all the appendages which homologate with the whole or with
parts of such a pseudembryo, even although they do not assume fully the characters of
a distinct animal form, I would propose the term pseudembryonic appendages. The
same prefix may distinguish the organs of the temporary zooid, where such exist,
pseudostome, pseudocele , pseudoproct, &c. The reason for the retention of this series
of terms, and for the rejection as applied to the provisional organism of the ordinary
terms “ embryo ” and “ larva,” will be fully discussed hereafter.
The first stage includes the development, structure, and life-history of the pseud-
embryo.
While the special external form of the pseudembryo is still perfectly retained, and
while its special functions are still in full activity, the form of the pentacrinoid embryo
is gradually mapped out within the provisional zooid, and the permanent organs of the
embryo are differentiated within its sarcode-substance. The pseudembryo then becomes
gradually distorted by the embryo developing within it, its special assimilative and loco-
motive organs disappear, and the external layer of its sarcode-substance subsides into the
518
PROFESSOR W. THOMSON ON THE EMBRYOGENY OF ANTEDON
general integument of the embryo, still retaining sufficiently the histological characters
of the pseudembryonic integument to leave no doubt that it is simply produced by its
modification and extension.
From the appearance of the first traces of the permanent embryonic structures within
the pseudembryo, the development of the pentacrinoid larva advances' steadily ; and there
is no natural separation into stages of its subsequent progress until the young Antedon
drops from the larval stem. At one period, however, during the development of the
pentacrinoid there is a marked change in the external form and in the anatomical rela-
tions of the larva, owing to the sudden widening out of the radial portion of the disk,
and the breaking through of the anal opening. Division of labour has been found
expedient in the present investigation, and my portion of the task ends just before the
development of the Pentacrinoid has reached this point. I think it only right, how-
ever, to mention that Dr. Carpenter, who has been at the same time working out the
later stages in the development of the Pentacrinoid and the structure of the mature
Antedon, has most freely communicated to me all his results. My description of the
development of the pentacrinoid larva has had therefore all the advantage of the light
thrown upon the earlier stages by Dr. Carpenter’s researches on the later.
The observations whose combined results have been condensed into the present com-
munication have extended over the last four years. I have had an opportunity each
season of watching the more or less favourable development of one or two sets of
embryos. As stated above, these observations have not in all cases thoroughly tallied ;
their inconsistencies depending, I believe, in some instances upon error of observation,
and in others upon actual discrepancies in the process of development under different
circumstances. In Arran, in June 1860, I had a most favourable opportunity of tracing
a single brood from the segmentation of the yelk almost to the maturity of the penta-
crinoid young. I took the opportunity to revise and check previous special observa-
tions ; and each stage of the development of this group was described and figured with
great care, and with the advantage of previous familiarity with the successive modifica-
tions in form. To avoid all possibility of confusion, I have incorporated in the following
detailed description those results only which were confirmed by these later observations ;
and all the figures of the free pseudembryos, and of the origin of the pentacrinoid form,
refer to the successive stages in the development of this single brood. On this occasion
the pseudembryos remained for perhaps a somewhat shorter time than usual in their
free condition, and their growth was early arrested by the development of the perma-
nent calcareous plates. The pseudembryos, however, during their brief independent
existence, attained their perfect and usual external form ; and the subsequent transitions,
though rapid, were normal.
The ovaries of Antedon have been frequently described. During the latter part of
summer, autumn, and early winter they can only be traced as delicate lines of whitish
stroma, beneath the integument of the upper (oral) surface of the pinnules, and imme-
diately beneath the tentacular canals which in the ordinary condition of the pinnules
EOSACETTS, LINCK (COMATTJLA EOSACEA OE LAMAECK).
519
lie in the groove of the calcareous joints. About the end of February or the beginning
of March, the integument of the pinnules becomes slightly turgid ; and this turgescence
increases till towards the end of May or the beginning of June, when the eggs are fully
formed.
The mature ovaries are short, entire, fusiform glands distending widely the inte-
gument of the pinnules, and provided with a special aperture which perforates the
distended skin on that side of the pinnule which is turned towards the end of the arm.
The aperture is bounded by a somewhat thickened ring of apparently elastic tissue,
which acts as an imperfect sphincter. Examining the ovary by compression shortly
after it has begun to enlarge, the meshes of the stroma (Plate XXIII. fig. 1) are found
to contain a clear mucilaginous protoplasm with minute ova in various early stages of
development. Tracing the development of the ova, the formative fluid first becomes
slightly opalescent, and a minute, highly refractive, lenticular body makes its appear-
ance, which subsequently declares itself as the germinal spot. This body remains some
time slowly enlarging without much further change. A delicate film now rises from
one side of it, and this film gradually extends till the germinal spot appears to be
attached to the inner wall of a spherical cell with perfectly transparent fluid contents,
the germinal vesicle (Plate XXIII. fig. 2, a-c). The blastema in the neighbourhood of
the germinal vesicle becomes slightly granular, and the granules accumulate so as to
form a distinct granular layer round the cell. This layer, the nascent yelk, is shortly
found to be invested by a delicate vitelline membrane ; but this membrane does not
appear to originate from the germinal vesicle as a nucleus, as in the case of the
latter from the germinal spot. The impression rather is that the surrounding fluid is
influenced to a certain distance by the chemical forces acting in the germinal vesicle,
and that a membrane is produced at the point of junction between the blastema so
influenced and the general fluid contents of the ovary. The egg now increases in size
without much further change in structure. The vitelline membrane rapidly expands
(Plate XXIII. fig. 2, cl-o), and its contents become more dense, till at length it has
attained a diameter of about ‘5 millimetre, and is entirely filled with a yelk-mass
composed of oil-cells of the usual form.
The ripe eggs are now discharged from the ovary ; they remain, however, for some
time (in some cases three or four days) entangled in the loose stroma of the ovary, and
hanging from the ovarian aperture like a bunch of grapes.
The testis resembles the ovary in form and situation. A transparent mucus distends
the integument of the pinnule. The fluid becomes opalescent, then granular, and
finally the cavity becomes filled with amass of fusiform parent cells (Plate XXIII. fig. 4).
The contents of these cells are at first perfectly transparent ; soon, however, they lose
their transparency and become granular, and at length the cells are found to contain a
progeny of ten or twelve minute spherical “ vesicles of evolution.” Bright refractive
spots, the heads of the spermatozoa, three or four in number, appear in each of these
secondary cells ; and finally, the walls of the parent cells and vesicles give way, and the
520
PROFESSOR W. THOMSON ON THE EMBRY 0 GrENY OF ANTEDON
cavity of the pinnule is filled with a mucilaginous liquid charged with myriads of mature
spermatozoa (Plate XXIII figs. 5 & 6).
The form of the spermatozoon is intermediate between that of a club on cards and a
spade (Plate XXIII. fig. 7), with a vibratile filament of great length attached to the
obtuse end. There is no special opening to the testis, so that the female may be at
once distinguished by the ovarian aperture. The seminal fluid seems to be discharged
by the thinning away and dehiscence of the integument. The spermatozoa are dispersed
in the water. Impregnation appears to take place after the discharge of the ova, but
while they are still hanging from the ovarian aperture.
An hour or two after impregnation the germinal vesicle disappears, or at all events
leaves its former superficial position. The yelk-mass contracts and becomes more opaque
and dense, leaving a clear space immediately within the vitelline membrane, which is
thus more clearly defined, perfectly transparent and structureless, with the surface
slightly and irregularly echinated (Plate XXIII. fig. 8). Consequently on the con-
traction of the yelk, a number of minute spherical pale yellow oil-globules are appa-
rently pressed out into the space within the vitelline membrane (Plate XXIII. fig. 11).
The appearance of the “ richtungs-blaschen ” may be very readily traced in the egg of
Antedon. At a point on the circumference of the yelk a very distinct globule, about
half the diameter of the germinal vesicle, with an obscure nucleus, passes out of the
yelk-mass into the surrounding space. In all the cases in which I have observed it,
this globule has been accompanied by two or three minute rounded granular masses.
Plate XXIII. fig. 14, a-c, are careful representations of three groups of these globules.
They remain perfectly distinct from the divisions of the yelk during the earlier stages
of segmentation ; at the close of this process, however, it becomes difficult to distinguish
them from the ultimate divisions of the mulberry mass. In Antedon , yelk-segmentation
is complete (Plate XXIII. figs. 9-13). Its first appearance is a slight groove passing-
inwards from the circumference of the yelk, immediately at the point where the so-called
“richtungs-blaschen” have been extruded. If the egg be now subjected to slight
pressure, a transparent nucleus may be observed in the centre ; and at each stage of
segmentation the nucleus may be readily detected in the centre of each segment. A few
hours after segmentation has been completed, the surface of the germ-mass becomes
slightly more transparent. The ultimate yelk-spherules are still sufficiently evident,
giving the surface a distinctly mammillated appearance (woodcut A).
This gradually disappears, the spherules seem to coalesce upon the outer surface,
remaining distinct a little longer towards the inner surface of this rudimentary germinal
membrane, and a few hours later they have become entirely fused into a continuous
structureless sarcode-layer (woodcut B). While these changes are taking place in the
outer layer, the central portion of the germ-mass becomes resolved into a mucilaginous
protoplasm sufficiently fluid towards the centre to allow of an active circulation of
granules and oil-globules, but apparently continuous with, and graduating into, the
lower surface of the more consistent peripheral layer.
A. Usual condition of the mulberry mass immediately after segmentation has been completed. B. Appearance
of the nascent pseudembryo after the coalescence of the ultimate spherules of the germ-mass. C. Pseu-
dembryo shortly before the rupture of the vitelline sac.
In this case the development of the pseudembryo from the germ-mass resembles in
every way the development of the embryo in most of the invertebrate groups ; on three
occasions, however, during the examination of a series of eight or ten broods, a whole
brood of embryos were evolved under somewhat different circumstances. The surface
of the mulberry mass became somewhat looser and more transparent, and under slight
pressure a large, somewhat darker and more consistent central nucleus was observed
(Plate XXI Y. fig. 1). This nucleus increased in size from hour to hour, the peripheral
portion of the contents of the vitelline membrane gradually liquefying and becoming
absorbed into the nucleus. At length the oval outline of the pseudembryo might be
traced through the flocculent mass of semitransparent semifluid yelk. The remainder
of the yelk now became completely transparent and liquid, the embryo increased rapidly
in size, and its form was more clearly defined through the wall of the vitelline sac
(Plate XXIY. figs. 1-4). I believe, however, that this latter is an abnormal mode of
development, depending probably upon imperfect aeration.
Observed during the process of development within the vitelline membrane, the
embryo is at first nearly regularly oval, and the surface appears to be uniformly ciliated.
I have never met with an instance in which the embryo escaped in this condition. In
all the cases which I have observed, the ciliated bands so characteristic of the pseud-
embryonic form have made their appearance before the rupture of the vitelline sac
(woodcut, C) ; and frequently the pseudembryo has become somewhat reniform, a de-
pressed ciliated patch indicating the position of the pseudostome. The pseudembryo
frequently, but not constantly, rotates slowly and irregularly within the vitelline sac,
the rotation depending evidently upon 4he action of the cilia on the surface of the
pseudembryo. Immediately after escaping from the vitelline membrane, the pseud-
embryo is about *8 millim. in length, oval, slightly enlarged towards one extremity, and
girded by four nearly equidistant transverse ciliated bands. It consists throughout of
very delicately vacuolated sarcode, which becomes more and more consistent towards
the periphery, where it forms a smooth firm surface, which is not, however, bounded by
any definite membrane. Towards the centre the substance becomes more fluid, and is
mdccclxv. 4 B
522
PROFESSOR W. THOMSON ON THE EMBRYOGENY OF ANTEDON
turbid with oil-cells and granules. At this stage distinct molecular motion may he
observed in the central portion, and a granular semifluid mass escapes if the larva be
ruptured by pressure. The surface is dotted over with the wider ends of large pyriform
lemon-coloured oil-cells immersed perpendicularly in the sarcode. Between these oil-
cells the sarcode is nearly transparent, containing merely a few scattered granules. The
ciliated bands project slightly above the general surface. They are greyish and granular,
and appear to be rather more consistent than the surface of the sarcode, which rises
up to them, sinking somewhat in the interspaces. The cilia are very long; they do
not vibrate with the regular rhythmical lash of ordinary cilia, but seem to move
independently, their motion regulating the rapidity and direction of the movements of
the animal in the water. There is a large tuft of still longer cilia in perpetual vibratile
motion at the narrower (posterior) extremity of the body. At first the pseudembryo
is simply barrel-shaped, and regularly hooped by the four parallel transverse ciliated
bands. Sometimes, while yet within the vitelline sac, but at all events within a few
hours after its rupture, the body becomes slightly curved, somewhat like a kidney bean ;
and on the concave surface, the third band from the anterior extremity arches forwards
towards the second band ; and in the wider space thus left at this point between the
third and fourth bands, a large pyriform inversion of the superficial sarcode-layer takes
place (Plate XXIV. fig. 7).
This inversion is narrower anteriorly, becoming wider and deeper towards the poste-
rior extremity. Its margins are richly ciliated. Simultaneously with the appearance
of this depression, a small round aperture may be observed immediately behind it, sepa-
rated from it by the fourth ciliated band, and close to the posterior tuft of cilia. This
aperture is surrounded by a ring of darker granular tissue, and the outline of a short
arched canal may be detected passing under the fourth ciliated band and uniting the
deep posterior extremity of the larger aperture, which thus becomes irregularly funnel-
shaped, with the smaller circular opening.
The large ciliated key-hole-like inversion of the sarcode is undoubtedly the pseudo-
stome ; and resembles closely in form and position the same organ in other echinoderm
pseudembryos. The loop-like canal beneath the posterior ciliated band is the extremely
rudimentary pseudocele, and the round aperture is the pseudoproct. The pseud-
embryo swims with either extremity in advance indifferently ; the anterior and posterior
extremities are therefore only defined at this stage by the relative positions of the mouth
and anus. It swims rapidly with a peculiar swinging semi-rotatory motion. The oral
surface is turned downwards in a state of rest. The pseudembryo sometimes remains
for several days, increasing in size till it becomes from 1*5 millim. to 2 millims. in
length, without undergoing any further change. In other cases indications of the areo-
lated calcareous plates of the Echinoderm appear within a few hours of the rupture of
the vitelline sac.
Usually not until the pseudembryo has assumed its mature and perfect form, but
sometimes much earlier, several minute calcareous spicula make their appearance beneath
EOSACETJS, LINCK (COMATULA EOSACEA OF LAMAECK).
523
the external layer of sarcode. The spicula are at first blunt irregular cylinders ; but
shortly they fork at either end, and at length, by repeatedly dichotomizing and anasto-
mosing, they form delicate plates of calcareous network. When definitely developed,
these plates are ten in number, and they arrange themselves in two transverse rings of
five each, within the wider anterior portion of the pseudembryo, the posterior row being
slightly in advance of the pseudostome. These plates are at first round and expand
regularly; the plates of the anterior row being arranged symmetrically above those
of the posterior series (Plate XXIV. fig. 7.). They are imbedded in the substance of
the sarcode, which for some time remains transparent within and without ; gradually,
however, the space within the plates becomes turbid and opaque, and at length a rounded
brownish granular mass fills up the lower portion of the cup formed by the calcareous
trellis. A series, varying in number, of delicate calcareous rings may now be detected,
forming a curved line passing backwards from beneath the centre of the lower ring of
plates, behind and slightly to the left of the mouth of the pseudembryo ; and a large
cribriform plate is rapidly developed close to the posterior extremity behind the anus
(Plate XXIV. fig. 6). The rings are regular in their inner contour, but externally they
are rough with minute branching spicula and excrescences.
About twenty-four hours later the pseudembryo still retains its original form, and its
rapidity of movement in the water is unimpaired. The anterior wider portion has
become still more bulbous and enlarged, and a thick layer of firm transparent sarcode,
thickly studded with columnar oil-cells, forms a dome-shaped arch over the anterior
extremity. The sarcode external to the calcareous framework is extremely transparent,
and the dark granular hemispherical brownish mass within the lower tier of plates is
more clearly defined ; while above it and within the upper part of the space included
within the plates, the outline of a second more transparent delicately granular hemi-
sphere has become apparent. The two rows of plates are now irregularly square in
outline, the plates of the lower series slightly contracted beneath, and those of the
upper tier above; so that the ten plates forming the two rows, and now placed in close
juxtaposition, form a delicate calcareous basket pentagonal in transverse section and
slightly contracted above and below. A hollow sheaf of parallel calcareous rods, united
together by short anastomosing lateral branches, is formed within each of the calcareous
rings of the series passing backwards from the base of the calcareous cup. These
sheaves are, as it were, hound in the centre by the calcareous rings, and the rods remain
irregular and constantly increasing in length at either end of the sheaf, the irregular
growing ends of the rods of one sheaf meeting and mixing with those of the sheaves
next it. Thus we have formed what at first appears to be a continuous curved calca-
reous rod; a slight amount of pressure, however, is sufficient to separate the joints from
one another, and to show its true structure. The base of the sheaf of rods passing
through the last ring of the series abuts against the centre of the upper surface of the
circular cribriform plate, now rapidly increasing in size, and becoming more defined in
contour, immediately behind the anus (Plate XXIV. figs. 8, 9, & 10).
4b 2
524
PROFESSOR W. THOMSON ON THE EMBRYOGENY OF ANTEDON
We have thus the rudiments of the “ pentacrinoid stage” of the Antedon clearly
defined and rapidly advancing in development within the body of the pseudembryo,
while the latter still retains in perfection its independent form and its special organs of
locomotion and of assimilation.
I have found it utterly impossible at this stage to trace the formation of the viscera
of the young pentacrinoid, on account of the close calcareous network in which the
nascent organs are enveloped. From its colour and position, however, there can be no
doubt that the mass occupying the base of the cup represents the origin of the stomach
with its granular hepatic folds, while the upper more transparent sarcode-hemisphere
indicates the nascent tissues of the vault, and at a subsequent stage originates the ambu-
lacral ring with its radial branches and the tissues of the young arms. The two rows of
plates, enclosing the viscera and forming the cup at this early period, represent the basal
and the oral series of plates, which are remarkably suppressed and modified during the
subsequent development of the crinoid. The jointed calcareous rod is the stem of the
Pentacrinoid, and the circular calcareous plate afterwards supports the round fleshy
disk by which the base of the stem adheres to its point of attachment. From six to
twenty-four hours later the pseudembryo becomes more sluggish in its movements, and
begins to lose its characteristic contour. The anterior extremity becomes somewhat
flattened, and then slightly depressed in the centre. The stem of the included crinoid
lengthens, and the sarcode of the body of the pseudembryo contracts towards it. The
pseudostome and pseudoproct become obscure and are shortly obliterated, the sarcode
forming a thick, smooth, uniform layer over the stem and over its terminal disk. The
two posterior ciliated bands disappear, the anterior bands remaining entire a little
longer, and still subserving the locomotion of the pseudembryo. The anterior bands
then likewise gradually disappear, the pseudembryo sinking in the water and resting
upon a sea-weed or a stone, to which it becomes finally adherent.
At this stage the pseudembryo is irregularly oval and in form slightly contracted
posteriorly, expanded and gibbous anteriorly, the anterior extremity flattened or slightly
cupped. The posterior extremity expands into a small rounded disk (Plate XXV. fig. 1).
Slightly compressed and examined by transmitted light, the Pentacrinoid larva has but
little altered from the description given above; the joints of the stem are somewhat
lengthened, and the cup is rather more open by the growth and slight separation of the
upper portions of the plates of the upper tier. The whole of the pentacrinoid is
entirely invested by a thick layer of transparent sarcode, which is merely the substance
of the body of the larva which has contracted uniformly over the body and stem of the
crinoid, its surface retaining, with the exception of the absence of the bands of cilia, the
same character as the surface of the pseudembryo, with the same pyriform oil-cells
arranged in the same way, and leaving the same interstices of nearly transparent deli-
cately vacuolated sarcode. The head of the crinoid now becomes more regularly pyri-
form, and the stem rapidly lengthens. The posterior disk becomes firmly and perma-
nently fixed to its point of attachment. The wide anterior extremity now shows a
EOSACEUS, LINCK (COMATULA EOSACEA OF LAMAECK).
525
distinct central depression, and the raised external rim indicates a division into five
crescentic lobes.
The whole cup gradually expands and increases in size. The five basal plates enlarge
and become more definite in form. Their upper edges are still irregular in outline,
somewhat crescentic, arching upwards towards the bases of the orals ; but the lateral
edges are now bounded by smooth straight calcareous bands, the sides of each plate
applied with the intervention of a narrow band of sarcode to the similar edges of the
two contiguous plates. The narrow lower edges of the basals are rough and irregular,
resting on the upper surface of the irregular ring-like rudiment of the centro-dorsal
plate. The oral plates likewise undergo a change in form. They become wider infe-
riorly, and the sides of the plates towards the lower margin curve outwards, the lower
borders thus becoming concave, the convexity turned inwards towards the centre of the
body. At the same time the upper edges, which remain narrow and rounded, curve
slightly forwards and inwards towards the opening of the cup. If the animal remain
undisturbed in well aerated water, when the development of the skeleton has reached
this stage, the five lobes (the “ oral lobes”) forming the edge of the calyx gradually
expand, till the cup assumes the form of an open bell (Plate XXVI. fig. 1). Imme-
diately on opening, at least five, and more usually fifteen, delicate, extremely extensile
tentacles are protruded from the cup. The mouth, with the organs immediately
surrounding it, is formed even before the separation of the oral lobes. It may be seen
occupying the centre of the cup (Plate XXVI. fig. 3) immediately after its expansion,
as a large patent aperture. When the cup is fully expanded, the transparent tissue
continuous with the five oral lobes, and forming the margin of the disk, seems to curve
over uniformly into the wide funnel-shaped central opening. The mouth, however,
frequently contracts, though it never appears to close completely ; and when contracted
it is bordered by a slightly thickened very contractile rim, which projects over the cavity
of the oesophagus and forms an imperfect sphincter. When this sphincter is relaxed
and the mouth fully open, it is easy to see down to the very bottom of the digestive
cavity, a sac-like space apparently simply hollowed out in the general sarcode-body
(Plate XXVI. fig. 3).
Commencing immediately within the mouth, a series of irregularly-lobed glandular
masses, of a pale yellowish-brown colour, project into the cavity of the stomach, curving
in an irregular spiral down to the bottom of the cup. These glandular folds are richly
clothed with long vibratile cilia. The merest film of sarcode separates their secretion
from the stomach-cavity. The slightest touch, even of a hair, ruptures them and causes
the effusion of a multitude of minute granules, some colourless and transparent, and
others of a yellow or brownish hue. There can be little doubt from their position and
colour that these lobes form a rudimentary liver. They appear very early in the penta-
crinoid, colouring the lower portions of its body in the earlier stages of its growth within
the pseudembryo. They increase steadily in bulk during its later stages, and with but little
change of character make up a large portion of the visceral mass in the adult Antedon.
526
PROFESSOR W. THOMSON ON THE EMBRYOGENY OE ANTEDON
A wide vascular ring surrounds the mouth, occupying nearly the whole of the space
between the lip and the base of the oral lobes. This ring seems to be simply hollowed
out in the uniform sarcode. Its walls are not contractile, it maintains a constant
diameter of about 0'08 millim. It is filled with a transparent liquid, which passes like-
wise into all its tubular appendages ; and as granules move rapidly in this fluid, the
walls of the ring would seem to be ciliated, though hitherto no cilia have been detected,
even in sections and under high powers. The upper and outer margin of the ring gives
origin to two classes of tubular tentacles. In a very few cases in which I had an oppor-
tunity of looking into the cup immediately after its expansion, the total number of these
appendages has been fifteen, five extensile, and ten non-extensile. I have never seen
fewer ; and I feel convinced that these, with the vascular ring from which they spring,
are developed towards the close of the pseudembryonic stage and within the closed cup ;
they are protruded so immediately after its first expansion.
Radially, the ring gives off five highly mobile, irritable, and extensile tubular tenta-
cles, one opposite each of the intervals between the oral lobes. The cavity of these
tentacles is continuous throughout, and immediately continuous with the cavity of the
oral ring. Their wall seems to consist of a simple contractile sarcode-layer, studded
with oval yellowish endoplasts. There is no definite differentiation of a contractile
fibrous tissue. Under a high power, however, the sarcode appears to have a longitu-
dinal arrangement ; this may possibly be due to motion among the particles producing a
play of light. The walls of these tentacles are produced into numerous delicate tubular
processes (Plate XXVI. fig. 3 e), their cavities continuous with those of the tentacles.
These processes are arranged in three or four irregular longitudinal rows. They are
extensile, their walls when extended are extremely delicate, transparent, and apparently
structureless. When contracted two or three delicate ring-like rugae appear on the
walls of each (Plate XXV. fig. 3). Each process is terminated by a minute three-
lobed slightly granular head. At the base of each of these processes there is a delicate
crescentic leaf-like fold, slightly granular, and most distinctly marked when the tentacle
is retracted. When one of the extensile tentacles is wholly or partially retracted, it is
thrown into obscure transverse wrinkles, which give it at first sight the appearance of
being divided by a series of dissepiments. When the tentacle is fully extended these
folds totally disappear. At the base of each of these five “ azygous tentacles ” there is a
conical thickening and enlargement of the sarcode-tissue, contracting outwards towards
the tentacle which is continuous with its apex, and whose cavity passes through it to
unite at its base with the oral vascular ring. This conical projection is the commence-
ment of the young arm. The azygous tentacle terminates it, and leads it out, as it were,
up to the point of bifurcation. The tentacle remains persistent for some time in
the angle between the two first brachial joints (Plate XXVII. figs. 1 & 3), and finally
becomes absorbed and disappears. These five azygous tentacles are the first of a
system of “ extensile tentacles” which are subsequently developed in very extended
series as appendages of the radial and brachial tentacular canals. In almost all cases,
EOSACEUS, LINCK (COMATULA EOSACEA OF LAMAECK).
527
as soon as the interior of the cup can be examined after its expansion, the number of
extensile tentacles has reached fifteen ; but from the one or two instances in which the
ten additional tentacles have been absent, there can be no doubt that they are developed
somewhat later than the five already described. They arise in five pairs, one tentacle
on either side of and slightly within the base of each of the azygous tentacles, which
they resemble closely in character. They commence as minute csecal diverticula from
the canal which passes through the enlarged base of the azygous tentacle, and become
rapidly developed into tubular prolongations. At this stage (Plate XXVI. fig. 1),
when the cup is open, the fifteen tentacles are usually fully extended, curving over the
edge of the cup in the angles between the oral lobes, in threes, the azygous tentacle
somewhat longer in the centre, and one of the paired tentacles on either side.
Interradially, opposite each of the oral lobes, there is a pair of short tubular tentacles,
their cavities likewise continuous with that of the oral vascular ring. These tentacles
appear simultaneously with the five azygous extensile tentacles, immediately on the
expansion of the cup. They are flexible, but not extensile, slightly club-shaped towards
the distal extremity, which is fringed on either side by a single row of short conical
tubercles. The base of these tentacles is involved in the contractile sarcode ring sur-
rounding the mouth. When the disk is fully expanded they lie in pairs up against
the inner surface of the oral lobes. They are frequently, however, gathered inwards
together, or singly curving over the mouth. They form part of a very characteristic
system of “ non-extensile tentacles,” which afterwards fringe the radial and brachial
grooves. At this stage, then, the oral ring usually gives off twenty-five tentacular
appendages, of which fifteen are radial and extensile, and ten are interradial and non-
extensile.
Imbedded in the sarcode at the base of each of the azygous tentacles, a peculiar
glandular body is very early developed. At first it consists of a minute vesicle con-
taining a transparent fluid. The vesicle gradually increases in size till it attains a dia-
meter of about 0'08 millim. in diameter. Its contents become granular, and at length
it has the appearance of a large cell with a special wall, included in a capsule formed
of a firm sarcode-layer, from which the cell can be turned out unbroken.
The cell contains a number of large, irregularly-formed, transparent, slightly granular
masses, which are set free by the rupture of the cell-wall. These masses are quite
colourless. They are coloured by carmine more deeply than the general substance
of the body, and after death they become immediately strongly coloured by the red
pigment set free from the perisom. I have been utterly unable to determine the
function of these bodies. They are produced in great numbers, during the growth of
the pentacrinoid, along the edges of the radial and brachial grooves, and are permanent
in the mature Antedon. The only speculation which seems to me at all feasible, a specu-
lation which derives some support from their peculiar affinity for colouring matter, is
that they are glands connected with the secretion of calcareous solution for the develop-
ment and nutrition of the skeleton, analogous to the calcareous glands so constantly met
528
PROFESSOR W. THOMSON ON THE EMBRTOGENY OF ANTEDON
with in the pseudembryos and young of some of the other Echinoderm orders. At this
early period no general body-cavity can be detected separating the wall of the stomach
from the body. The stomach seems to be simply excavated in the structureless body-
substance, and the organism corresponds generally with the Ccelenterate type. The
external sarcode-layer still retains much the same character which it possessed in the
pseudembryonic stage. Its basis is transparent and structureless, with imbedded pyri-
form oil-cells, endoplasts, and granules.
The stem now gradually lengthens, by additions to either end of the sheaf-like calca-
reous cylinders which form the axes of the stem joints, and by the addition of new rings
which rapidly become filled up by the vertical tissue, at the top of the stem, imme-
diately beneath the rudiment of the centro-dorsal plate (Plate XXVI. fig. 2). The disk
of attachment becomes opaque by the addition of calcareous matter, and is firmly fixed.
The centro-dorsal ring (Plate XXVI. fig. 2) is more definite in form, though it is still
simply perforated in the centre, and in connexion with the sarcode-axis of the stem,
and bears no traces of dorsal cirri. The basals expand and form a wide, nearly con-
tinuous cup. By the rapid expansion of the body, five diamond-shaped spaces are left
at the points where the upturned angles of two oral plates are opposed to the bevelled-
off upper angles of two adjacent basals. In these spaces cylindrical spicula appear,
which soon become club-shaped, dichotomize, branch, and anastomose into delicate
net-like superficial plates, irregularly oval, slightly produced superiorly, their upper,
narrower portions resting beneath, and supporting, the gradually extending sarcode pro-
jections which are terminated by the azygous tentacles (Plate XXVII. fig. 1). The
equatorial portion of the body, the band between the upper edges of the basals and the
lower edges of the orals, now rapidly expands. The five young arms extend outwards,
their bases carrying out with them a zone of sarcode which gives the central portion of the
body a great additional width. The oral plates maintain their original position, so that
they are now completely separated from the basals by this intervening equatorial band ;
and are left, a circle of five separate plates, each enclosed in its sarcode-lobe, on the
centre of the upper surface surrounding the mouth, and enclosing the ten non-extensile
tentacles only. The first radial plates begin to thicken, especially towards the upper
margin, and this thickening is produced by the growth, beneath the cribriform super-
ficial calcareous film, of a longitudinal mass of tissue of the same character as that
which forms the cylindrical axis of the stem joints. On the lower surface of each arm,
in linear series, immediately above the first radials, two spicula, horseshoe-shaped, with
the opening above, appear almost simultaneously, and become quickly filled up with
elongating sheaves of longitudinal trellis-work. These extend along beneath the
extending arms, and indicate the second radials and the radial axillaries.
The upper surface of the arms now becomes grooved by the development, on either
side of the central vessel, of a series of delicate crescentic leaves. These leaves are
hollow, communicating by special apertures with the radial vessel, and filled with fluid
from it. At the base of each of the leaves there is a pair of tentacles forming a group
EOSACEUS, LINCK (COMATULA EOSACEA OE LAMAECK).
529
with the leaf, and along with it communicating with the vessel. One of these tentacles
(the distal one) is somewhat larger than the proximal; they are both slightly club-
shaped, the club-shaped extremity fringed on either side with conical papillae. They
are non-extensile, and resemble in every particular the ten non-extensile tentacles early
developed from the oral ring. A group consisting of a crescentic leaf and two non-
extensile tentacles lies immediately at the base of each extensile tentacle, and a little
lower down the arm (Plate XX,VII. fig. 3 d). Minute spicules, some of them simple or
key-shaped, and others expanding into a cribriform film, appear in the superficial sar-
code-layer along the back or edges of the arms ; and, usually at the base of each of the
tentacles, irregularly imbedded in the sarcode-substance, there is one of the calcareous
glands.
Immediately on the expansion of the equatorial portion of the cup, the wall of the
stomach becomes separated by a distinct body-cavity filled with fluid, from the body-
wall. The stomach seems to hang in this cavity as a separate sac, attached to the body-
wall here and there by sarcodic bands and threads. As the disk expands, the radial
canal may be distinctly seen rising from the oral ring, crossing the narrow disk and run-
ning along the upper surface of the arm, communicating on either side with the various
tentacles and respiratory leaves, and ending at the extremity of the arm in the azygous
tentacle. Beneath the radial canal a tubular extension of the perivisceral space passes
along the radial grooves. This series of vessels, for which Dr. Carpenter proposes the
term “ cceliac canals,” afterwards extends throughout the whole length of the arms. In
the mature Antedon Dr. Carpenter has observed a third vessel intermediate between
the coeliac and tentacular canals; but no trace of this vessel can be detected in the
earlier stages in the development of the pentacrinoid.
A little later, the end of the arm shows a tendency to bifurcate, and two half rings,
with their enclosed sheaves of calcified tissue, give the first indication of the first two
brachials. At the stage which I have described the arm is free, from the base of the
second radial ; at a later stage the visceral sac extends to the bifurcation, and the whole
of the radial portion of the arm becomes included in the cup and disk. The azygous
tentacles go no further than the bifurcation. They remain for some time in the centre,
between the two divisions of the arm, while secondary branches from the radial canal
run on in the brachial grooves. About the period of the development of the second
radials, a forked spicule makes its appearance in one of the interradial spaces between
the upper portions of two of the first radial plates. This gradually extends in the usual
way till it becomes developed into a round cribriform superficial plate.
Simultaneously with the appearance of this “ anal ” plate, a ceecal process like the
finger of a glove rises from one side of the stomach and curves towards the plate. The
plate increases in size, becomes enclosed in a little flattened tubercle of sarcode, and
maintaining its upright position it passes slightly outwards, leaving a space on the edge
of the disk between itself and the base of the oral plate immediately within it.
Towards this space the csecal intestinal process directs itself. It rises up through it
mdccclxv. 4 c
530
PEOFESSOE W. THOMSON ON THE EMBEYOGENY OF ANTEDON
in the form of an elongated tubular closed papilla. The summit of the papilla is finally
absorbed, and a patent anal opening is formed. The details of these later changes
belong, however, more properly to a subsequent stage.
Having thus described generally the development of the Pentacrinoid stage of Ante -
don up to a point when a marked change takes place in its structure and economy, I
shall now discuss, in somewhat fuller detail, certain general considerations arising from
the successive steps of the developmental process.
The relations of the Pseudembryo. — In Antedon the germ-mass is resolved, at all
events to a great extent, into sarcode having the peculiar delicately vacuolated structure
so characteristic of this zoological element. The sarcode contains multitudes of “ endo-
plasts and of oil-cells and granules scattered through its substance, but these latter I
must regard merely as stores of various organic compounds elaborated as secretions and
excretions during the development of the organism. In the centre of the sarcode zooid
there is usually a darker nucleus, indicating a special accumulation of granular matter.
I have satisfied myself, however, that this condition is not essential, as in some cases in
which the young were developed in clear water, with a scanty supply of nourishment,
the pseudembryo became transparent throughout. Still it is conceivable that a germ of
the original substance of the mulberry-mass may be retained to originate the Crinoidal
embryo. At all events, the temporary organism which I have termed the Pseudembryo
is entirely dependent for its form and structure upon the sarcode into which the whole
or the greater portion of the germ-mass is resolved. This sarcode zooid possesses all the
peculiarities of the sarcode organisms among the Protozoa and the lower forms of the
Ccelenterata. Its external surface is richly ciliated, and if lightly touched with a bristle
it moves off rapidly, by means of these cilia, in a direction opposite to the touch, giving
-evidence of a high degree of irritability and power of automatic motion, without the
slightest trace of a special nervous system. During the early stages of its development,
and before the differentiation of a special assimilative tract, the body increases rapidly
in size ; the sarcode is therefore capable, as in the case of the astomatous Protozoa, of
absorption over the whole external surface, and of assimilation throughout the entire
internal substance.
Whatever at this stage may be the relations of the granular nucleus of the pseud-
embryo, I believe the external ciliated absorbent and irritable sheet of sarcode must be
regarded as a special provisional organ for the nutrition and aeration of the nascent
embryo. Dr. Carpenter * has already suggested a correspondence between the zooid
pseudembryo in the Urchins and Starfishes, and the temporary embryonic structures in
* 44 "We Fere find the yolk-mass converted into a structure, ■which, is destined only to possess a transient
existence, and which disappears entirely by the time that the development of the offset from it has advanced
so far that it begins to assume the characters of the permanent organism. This, however, is what takes place
in the higher vertebrata ; for the structures first developed in the egg of the bird hold nearly the same rela-
tion to the rudimentary chick, that the 4 Pluteus ’ bears to the incipient Echinus or Ophiura, or the 4 Bipin-
naria’ to the incipient Starfish.” — Principles of Comparative Physiology, 4th edit. p. 568.
EOSACETTS, LINCK (COMATULA EOSACEA 0 E LAMAECK).
531
the higher animals ; and I have developed the analogy* still further, in tracing the conti-
nuity of the cavity of the pseudembryonic appendages in Asteracanthion with the vascular
system of the young Starfish. The sarcode cylinder preceding and afterwards investing
the embryo of Antedon must undoubtedly be referred to the same category of structures.
As the development of the pseudembryo proceeds, a large funnel-shaped ciliated
pseudostome with an obscure intestine and a minute pseudoproct are formed ; and the
zooid, which at first resembled a Plagiophrys or Difflugia in simplicity of structure, may
now be compared to a Vorticella or Bursaria.
The alimentary system is, however, extremely simple. The digestive tract is rudi-
mentary, and the function of the large funnel-shaped oesophagus, with its loop-like
pseudocele, seems to be to produce a rapid and special current of fresh water to the
general mass of absorbent sarcode rather than to localize the assimilative function.
The functional activity of the pseudembryo appears to reside essentially in the peri-
pheral layer. During the earlier stages of its development the central portion consists
of a dusky granular semifluid substance, increasing gradually in opacity, and exhibiting
active molecular motion; afterwards the centre is devoted to the building up of the
viscera of the embryo at the expense of this previously secreted pabulum ; hut during
the earlier stages of the growth of the embryo, its increasing bulk does not appear to
interfere in any way with the functions of its nurse. Absorption, as indicated by
increase in size and weight, is at no period more rapid than when the pseudembryo
is losing its special organs of locomotion and assimilation, and becoming torpid and
distorted by the growth of the included organism.
The hollow cylinder of sarcode forming the independent living body of the pseud-
embryo, at a certain stage loses its cilia, its special organs of assimilation are obliterated,
it appears to merge its distinct life in a second harmonized combination of organs which
has grown up within it, and the whole layer, without the slightest change in structure,
subsides into the perisom of the Pentacrinus.
Histologically the ectosarc of the pseudembryo must be regarded as having been the
integument of the Crinoid throughout, its functions highly modified and exalted for a
special purpose. The hard structures of the perisom, the two rows of cup-plates and
the stem, are accordingly developed in the substance of this integument ; and the out-
line of the Crinoid is thus frequently mapped out in calcareous trellis-work before there
is the least trace of the differentiation of internal organs. The stem has clearly no con-
nexion with the viscera whatever, it is a temporary appendage to the radial skeleton.
Until we have accurate details of the embryogeny of a more extended series from the
various Echinoderm orders, I believe it would be premature to discuss at length the
morphology of the pseudembryo of Antedon. At present we are acquainted with many
species belonging to widely differing genera, scattered apparently irregularly through
the four orders of the subkingdom, which produce independently organized pseud-
* “ On the Embryology of Asteracanthion vioTaceus (M. & T.),” Quarterly Journal of the Microscopic Society,
1861, p. 99.
4 C 2
532
PKOEESSOR W. THOMSON ON THE EMBRYOGENY OE ANTEDON
embryonic nurses, presenting a distinct bilateral symmetry in the arrangement of their
alimentary system and natatory apparatus. A certain community of plan appears to
run through the swimming group described by Professor Muller ; but subsequent
observations would seem to indicate that so high a development of the pseudembryo is
exceptional.
In genera closely approximated to those in which the pseudembryo is most highly
organized, or even in allied species of the same genus, the pseudembryonic appendage
is reduced to a mere rudimentary vascular tuft, or to a simple investment of sarcode.
My own observations would lead me to suspect that the independent development of
the pseudembryo may be greatly modified, even in the same species, under different
circumstances of light, warmth, aeration, and nourishment.
The pseudembryo of Antedon resembles very closely what Professor Muller has
described as the “ pupa stage ” in certain Holothuridea. The young Holothuria, how-
ever, has in these instances, according to Muller’s observations, passed through the
phase of a pseudembryonic zooid (Auricularia), with a special mouth and alimentary
canal, special natatory lobes, and a regular bilateral symmetry, before assuming the
pupa form of a closed sarcode-cylinder girded with ciliated bands and devoid of special
organs. In Antedon the “Auricularia” and the “pupa” stages are, as it were, fused
into one. The “pupa” form is at once developed from the germ-mass, but it is pro-
vided with the assimilative organs of the Auricularia, though in a very rudimentary
degree. Further metamorphosis proceeds very similarly in both cases. In both the
organs of the young are gradually differentiated within a sarcode-cylinder, the branchial
tentacles finally protruding through an anterior sarcode dome. The close analogy is
highly marked in the Synaptidse, the group whose metamorphoses have been observed
by Muller, in which, as in the Crinoids, the oral tentacles are highly developed at the
expense of the vessels of the ambulacral region. One or two remarkable differences,
however, exist. In Antedon no part whatever of the alimentary canal is adopted by the
nascent Crinoid. In Antedon the development of the organs of the embryo is confined
to the anterior region of the pseudembryo, the posterior portion containing the stalk, a
temporary appendage. In the Holothuridea the whole pupa passes by simple metamor-
phosis into the body of the perfect form, the apical pole being occupied by the excre-
tory orifice of the alimentary canal. In the Holothuridea the madreporic tubercle and
the sand canal, though frequently extremely rudimentary in the mature form, seem
uniformly conspicuous during the development of the young. In the pseudembryonic
stage of Antedon no trace of this organ has been observed.
I believe that, in zoological language, the term “ embryo ” has hitherto been under-
stood to indicate a young animal during the early stages of its development ; an orga-
nism which is produced by the differentiation of the whole or of part of the segmented
yelk, and which is a stage in progress towards the mature form of its species. Any
accessory or deciduous parts have usually been termed embryonic appendages ; but these
embryonic appendages have always been regarded as parts of the embryo, although
EOSACETTS, FIACK (COMATULA EOSACEA OF LAMAECK).
533
temporary, yet partaking during their life, of the life of the embryo, and as affording ho
evidence of possessing independent vitality. I imagine that as the term Embryo has not
been applied to the yelk, or to the germ-mass before the separation of the organs of the
young, it would be a like misapplication of the term to apply it to any stage in the
development from that germ-mass of a being whose organs do not homologate with, and
never by any subsequent metamorphosis become converted into, the analogous organs of
the perfect form. Again, according to the ordinary conception of a “ larva,” it is a stage
in the development of an animal during which its external form differs to a greater or
less degree from that of the “imago” or mature form, and its organs are greatly modi-
fied for the performance of certain functions at the expense of others ; but the organs
of the larva are essentially the organs of the imago ; and the individual which is formed
of the sum of these organs, and which manifests vital phenomena, is the same individual
which subsequently lives as the imago. It is utterly inconceivable that the larva and
the imago should exist as separate individuals at the same time. The relations of the
pseudembryo are entirely different. It is developed from the germ-mass as a distinct
animal form, manifesting a combination of vital phenomena, through a sum of organs
which attain a distinct maturity of their own, and which never pass in combination into
the sum of the organs of the perfect being. So complete is this independence, that in
cases where this type of the reproductive process is carried out most fully, as in Bipin-
naria, the embryo is at a certain period cast off from the pseudembryo, and both beings
continue for some time to manifest independent life. I would therefore define a
“pseudembryo” or a “ pseudembryonic appendage” as any provisional appendage pro-
duced from the germ-mass, which manifests the functions of organic and animal life
through the medium of a combination of organs which precede and do not homologate
with the organs of the true embryo. This appendage may be reduced to a condition of
extreme simplicity. It may exist merely as a layer of structureless sarcode, ciliated,
and manifesting the form of life characteristic of the simpler Protozoa ; within which
the organs of the embryo are gradually built up.
In most, however, if not in all the invertebrate groups, the so-called embryo differs
greatly in external form from the mature organism.
It usually commences in aquatic animals as a “ ciliated germ ” ; and in this condition,
whether within the vitelline sac or free after the rupture of the sac, it increases in size
by absorption through the general surface. Very usually various lobes and fringes are
produced, frequently richly ciliated, extensions of a transparent sarcodic investing layer,
within which — but bearing to it only obscure relations in form — the nascent organs of the
true embryo are slowly differentiated. During this period the permanent organs, so far
as their special functions are concerned, are utterly inert. They are merely growing.
The rudiments of the alimentary canal are being laid down, but probably the mouth
has not yet “broken through.” The entire zooid, however, is by no means inactive.
It moves rapidly through the water, its movements beautifully characteristic, and appa-
rently guided by an obstruction-perceiving and light-perceiving instinct.
534
PROFESSOR W. THOMSON ON THE EMBRY 0 GEN Y OE ANTEDON
The perfect organic and relative life of this being, closely comparable to the life of
the most highly gifted members of the protozoic snbkingdom, does not certainly exist
in the sum of the permanent organs ; it resides, I believe, simply in a pseudembryonic
sarcodic layer, endowed with the same properties which this zoological element possesses
when isolated, as in the Protozoa. Gradually the sarcode eliminates from the products of
its own assimilation the constituents, and elaborates the tissues, of the permanent special
organs; and when these are sufficiently developed, it loses its own individuality, its
vital activity passing into the organs which it has produced, and performing through
their medium more effectively and condensedly, functions, which, as a transient nurse-
layer, it performed in a manner perfect as to its simple object of temporary nutrition,
though somewhat feeble and diffuse. In respect to the essentials of this process, some
of the Holothuridea among the Echinodermata seem to conform almost exactly to the
ordinary Invertebrate type. The pseudembryonic sarcode-layer is here little more special
or independent than it is in the embryos of the Annelids and Mollusks, and infinitely
less so than in some Turbellarians ; and the transition from this condition, through the
Crinoids, in which a short alimentary canal is formed in the sarcode layer, — and the
“Plutei” in which the “ Echinoderm disk” with its accompanying permanent organs is
developed within the pseudembryo and covered by its general integument, the whole
substance of the pseudembryo being finally absorbed into the embryo, — to the “ Bipin-
naria,” in which the independent life of the pseudembryonic zooid is apparently carried
to its limit, is so perfectly gradual as to leave no doubt whatever of the uniformity of
the embryogenic plan.
This being the case, that is to say, a vast number of invertebrate embryos combining
in their earlier stages pseudembryonic appendages possessing independent vitality with
the nascent organs, no special divergence from the ordinary mode of development is to
be anticipated in cases in which the pseudembryo attains unusual individual indepen-
dence. We find accordingly the earlier stages in the development of the pseudembryo
in the Echinoderms conforming closely to the general mode of development of the
“ embryo” of aquatic invertebrates.
The earlier stages in the development of the Tissues of the Pentacrinoid.
The general connective tissue. — As stated above, the general transparent investment
which during the earlier stages of its development makes up the greater portion of the
substance of the pentacrinoid, is produced by the gradual extension and modification of
the sarcode substance of the pseudembryo. The pseudembryo is moulded from the
germ-mass, and at first its surface retains the mammillated structure, the result of the
ultimate segmentation of the yelk. At first each spherule retains a trace of the original
enclosed endoplast ; this, however, shortly disappears. No cell-membrane can be detected
investing these spherules at any period. An hour or two after the rupture of the vitel-
line sac, the mammillated structure entirely disappears, the ultimate spherules being
fused into a structureless layer. The external layer is firm and consistent. If the
ROSACEUS, LINCK (COMATULA ROSACEA OE LAMARCK).
535
pseudembryo die at this stage, shortly after its death, a delicate film is sometimes
separated from the surface of portions of the body, similar to the film which is
observed under similar circumstances on the surface of Infusoria. I do not believe,
however, that this film previously existed as a special membrane; but am rather
inclined to think that it is produced after death by the coagulation of a layer of mucous
excretion. Pyriform capsules of considerable size, about 0-03 millim. in diameter,
are imbedded here and there in the superficial layer. These cells are of a pale yellow
colour, full of a yellow fluid, which when the cell is crushed escapes as a round refrac-
tive globule. The wide end of the capsule is superficial, the narrower extremity passes
inwards and ends in a delicate thread-like process, which is lost in the substance of the
sarcode.
I have been able to detect no special wall to these capsules, the fluid of which seems
simply to be enclosed in a pyriform space in the continuous sarcode : I regard these as
reservoirs of oil.
The peripheric layer is nearly free from granules ; but passing from without inwards,
minute granules, compound granular masses, and endoplasts become more numerous;
the sarcode at the same time apparently losing in consistency, till at length, towards
the inner surface of the consistent perisomatic layer, it becomes densely granular, and
no distinct line of demarcation can be detected between the sarcode which still retains
a certain consistency, and the central semifluid protoplasm, in which the granules
exhibit active molecular motion. The outer layer, when compressed and examined with
a high power, exhibits between the endoplasts and oil-cells a very finely vacuolated
structure. Minute spaces, somewhat like the lacunae of bone, filled with a clear liquid,
are scattered through the sarcode ; and uniting these there is a system of exceedingly
delicate tubules which may be compared to the canaliculi ; they are much less nume-
rous, however, only about six or eight apparently radiating from each lacunar space.
Even while under observation, the size of these spaces appears to vary, one or two which
were prominent in one part of the field gradually contracting and becoming indistinct,
while others previously scarcely visible seem to expand into view. I believe that this
appearance is caused by the circulation of fluid through the system of vacuoles and
vessels by movements depending upon the general contractility of the body-substance.
Near the close of the free stage, when the embryo is beginning by its growth to distort
the form of the pseudembryo, the integument of the wider anterior extremity of the
pseudembryo immediately above the mouth of the embryo seems to become columnar in
structure and opaque with closely packed long oil-cells, arranged vertically, and forming
a kind of dome. In the earliest fixed stage this dome gradually splits up into the five
oral lobes, each with its enclosed oral plate.
The devlapment of the Skeleton. — To make the description of the development and
relations of the parts of the calcareous skeleton of the pentacrinoid stage of Antedon
intelligible, I shall in the first place describe very briefly the arrangement of the hard
parts in the mature Antedon and in some nearly allied forms. I shall touch on this
536
PROFESSOR W. THOMSON ON THE EMBRYOGENT OE ANTED ON
part of the subject lightly, as Dr. Carpenter is preparing an elaborate memoir on the
skeleton of Antedon. I adopt, in concert with Dr. Carpenter, a nomenclature differing
very slightly from that proposed by M. de Koninck in his valuable work on the fossil
Crinoids of the Carboniferous System of Belgium. I accept for convenience of descrip-
tion the division of the body of a Crinoid into three parts, the stem, the head, and the
arms. The head consists of two hemispheres, a dorsal or apical, and an oral hemisphere.
The former I shall term the cup of the Crinoid, and the latter the disk. It must be
remembered, however, that all the radial portions of the head belong morphologically
and physiologically to the arms. In the earlier stages of development the radial plates
of the cup, and the radial vessels of the disk, form the budding arms ; and it is only at
a later period that a distinction is produced between radial and brachial portions, by
the development of the visceral mass and the extension of the space for its accom-
modation.
The mature Antedon has no true stem. The cup is closed beneath by a large circular
plate hollowed out above into a small rounded chamber. The inferior convex surface
of this plate in Antedon rosaceus is pitted with a series of small rounded depressions
perforated in the centre with minute channels communicating with the cavity of the
plate. Into these depressions are inserted a number of jointed calcareous cirri. I
shall term the circular plate the “ centro-dorsal plate,” and the appendages the “ dorsal
cirri.” The centro-dorsal plate in Antedon does not belong to the cup. It represents a
coalesced series of the nodal stem-joints in the stalked Crinoids.
In Pentacrinus {Neocrinus) asterias (L.), the stem grows by additions immediately
beneath the row of basal plates of the cup. These plates are five in number, inter-
radial, wedge-shaped, their outer wider ends knob-like, heading and corresponding with
the salient angles of the pentagonal stem. Their inner narrower ends nearly meet in
the centre, each being only slightly truncated and emarginated, so that the five grooved
ends may unite in forming the walls of a canal, which is continuous with the central
canal of the stem, and through which the central sarcode-cylinder of the stem passes to
branch to special perforations in the first radials. The lower surface of each basal plate
is hollowed by a longitudinal groove crenated on the edges, and the five grooves are so
arranged that when the basals are in position, they form together a star-like mould, in
which the joints of the stem are formed. This cavity holds from three to four stem-
joints at a time; one extremely small at the bottom of the mould, the others gradually
increasing in size and gradually forced out and added to the lengthening stem, by the
growth of those behind them.
The joints developed in this position are all nodal, that is to say, they subsequently
bear whorls of cirri. The internodal joints, varying in number in different species,
are developed afterwards between these, each new internodal joint originating apparently
immediately beneath the nodal joint.
The dorsal cirri represent a varying number of compressed whorls of the stem-cirri
of stalked species which possess such appendages.
EOSACEUS, LINCK (COMATULA EOSACEA OF LAMAECK).
537
The centro-dorsal plate with its dorsal cirri in Antedon is therefore the homologue
of the stem with its cirri in the stalked Crinoids.
The true cup in the mature Antedon consists inferior] y of a delicate rosette of more
or less fully coalesced small cribriform calcareous plates ; which have been shown by
Dr. Carpenter, in a series of beautiful observations, to be the remains of the row of
five basal plates which occupy so prominent a place in the cup of the Pentacrinoid.
This rosette is completely concealed in the cavity of the ring formed by the first five
radials. Around the basal rosette, and alternating with its segments, five elongated
calcareous blocks, triangular in transverse section, the first radial plates, form a column
within the base of the cup. In A. rosaceus these plates are entirely concealed by the
centro-dorsal plate and by the series of second radials. In some species of the genus
Antedon , they project beyond the centro-dorsal plate, forming above its upper edge a
closed ring which supports the series of second radials. The centro-dorsal plate, the
basals, and the first radials are immoveably cemented together ; they do not, however,
coalesce, and may be easily separated after boiling in weak caustic potash. A ring of
five second radial plates placed in close contact, form, externally, the base of the cup in
Antedon rosaceus, resting within upon the upper surfaces of the first radials, and exter-
nally upon the edge of the centro-dorsal plate.
Kesting upon the second radials, we have next a row of five triangular axillary radial
plates, each bevelled above into two diverging surfaces for the articulation of the first
brachial joints. The axillary radials are not in immediate contact laterally, they are
separated by minute wedge-shaped prolongations downwards of the perisom of the disk.
In Antedon rosaceus, the basals, and the first, second, and axillary radials form the whole
of the skeleton of the cup.
In certain species of Antedon, as in A. Milleri (Muller, sp.), a series of five minute inter-
radial plates are intercalated between the angles of the axillary radials, and in other
forms, as in A. Solaris (Lam., sp.), and A. tessellatus (Muller, sp.), the whole of the
perisom of the disk is covered with a pavement of irregular flat plates. We are unac-
quainted with the development of Pentacrinus ( Neocrinus ) asterias (L.), but in the
mature form the perisom of the disk is continuously tessellated, and some of the plates
pass irregularly downwards between the axillary radials. In Pentacrinus ( Neocrinus )
decorus (nob.), the surface of the disk is rough with irregularly scattered blocks, like
fragments of perforated bricks ; and these descend into the spaces between the axillary
radials, though without any regular arrangement.
The basal and oral plates. — The first portions of the skeleton which appear are the
two rings of five plates each, the plates of the upper ring directly superposed on those
of the lower, which form the trellised basket, completely enclosing the viscera of the
Pentacrinoid during the early stages of its growth within the pseudembryo. The
plates of the upper tier subsequently extend into the five oral lobes, and remain as five
valve-like interradial oral plates during the greater part of the pentacrinoid stage.
The lower series are the basals. These are permanent, with some remarkable modifi-
MDCCCLXV. 4 D
538
PROFESSOR W. THOMSON ON THE EMBRYO OENY OF ANTEDON
cations in form, in the mature Antedon. These ten plates appear simultaneously as
delicate spicula imbedded within the firm peripheric layer of the pseudembryo, usually
only a few hours after its escape from the vitelline sac, and before there is any trace of
the permanent organs of the embryo.
The spicula are hollow throughout. They are at first simple and cylindrical ; shortly
they become club-shaped at each end; each thickened end then divides into two
diverging branches, equal in length to the original rod ; these fork in their turn, till on
their second bifurcation their branches meet and coalesce with the corresponding
branches from the opposite end of the original spiculum. By thus constantly branching
and anastomosing on one plane, the spiculum extends into a delicate net-like plate, the
meshes of which are at first irregularly hexagonal, but afterwards become rounded.
The extending calcareous tubes are constantly closed, and constantly hollow to the end.
They appear to grow by the molecular removal of calcareous matter from the back of
the growing point, and its deposition in advance. At first all the ten plates are round ;
but as they expand they become irregularly square, their edges during the free condition
of the embryo remaining rough with sprouting spicules.
About the time of the fixing of the pentacrinoid, the basals, which have now assumed
a somewhat definite form, narrower beneath and expanding above, have their lateral
edges bounded by straight lines, so that the edges of two adjacent plates are closely
applied to one another. Even after their edges have become thus defined, the plates
go on steadily increasing in size, apparently by interstitial growth. The upper edges of
the basals still remain rounded and rough. Their lower edges are likewise irrregular,
but these soon become obscured by the growth of the centro-dorsal ring. The oral
plates extend principally upwards into the oral lobes, where they become lengthened and
somewhat contracted, their edges fringed with diverging pointed spicules (Plate XXVI.
fig. 1). . As development proceeds they change somewhat in form. The upper angle is
slightly depressed, and the sides at the inferior angles are raised, the raised edges at
that stage lying up against the sides of the second radials. Absorption of the inferior
portion of the oral plates commences about the time of the appearance of the first
brachial joints and of the anal plate (Plate XXVII. fig. 1). Both basal and oral plates
consist at first of a delicate cribriform calcified film, formed by the lateral extension of a
single layer of calcareous tubing only. As they increase in size, however, they gradually
thicken, and this thickening is effected by the network sending in from its inner surface
irregular processes which branch and unite to form a second layer not quite so regular
as the first, but resembling it in general character. This process is repeated till the
plates have attained the required thickness. In the oral plates the thickening is very
slight, and is confined to the lower portion of the plates.
The stem. — As described above, shortly after the appearance of the spicula indicating
the basal and oral plates, a chain of six or seven calcareous rings may be observed curving
from the centre of the space between the bases of the basal plates ; behind, and usually
somewhat to the left of the pseudostome and pseudocele, and abutting against a round
EOSACEITS, LINCK (COMATTJLA EOSACEA OE LAMAECK)/ 539
cribriform plate which makes its appearance at the same time close to the posterior
extremity of the pseudembryo, behind and below the pseudoproct. Immediately beneath
the basal plates an irregular calcareous ring is early formed, considerably wider and
broader than the ordinary rings of the stem. This ring, which is subsequently deve-
loped into the permanent centro-dorsal plate, gradually thickens and becomes more
regular in form, maintaining its position at the top of the stem, the lower edges of the
basal plates resting on its upper surface. During the earlier stages of the growth of the
pentacrinoid it is simply a circular band of the ordinary calcified areolar tissue, enclosing
a sheaf of the peculiar fasciculated tissue of the stem, gradually enlarging, with a central
aperture continuous with the bore of the tube-like stem-joints. It is not till some time
after the latest stage described in the present memoir, that the rudiments of the first
dorsal cirri appear round its lower contour. The rings which originate the ordinary
stem-joints commence as small curved hollow spicules. At first they may often be seen
open and imperfect ; afterwards they completely close (Plate XXIV. fig. 6). The inner
surfaces of the rings are smooth, the outer roughened with projecting branches. I have
only once or twice seen the rings of the stem in this early simple stage. Very soon after
their appearance, usually before the pseudembryo has attained its full size, a hollow
sheaf of calcareous rods united by minute calcareous trabeculae arises within each ring.
The stem-joint increases in length by additions to each end of these cylinders. The
centre of the cylinder is occupied by a consistent sarcodic thread running through the
whole length of the stem. At this stage no fibrous tissue can be detected, either mixed
with the calcified tissue or in the outer perisom. Additions are made to the length of
the stem by the formation of new rings immediately beneath the centro-dorsal plate, the
new rings becoming, as in the former case, gradually filled up by cylinders of linear cal-
cified tissue. As the calcareous axis of the stem increases in width, the original rings
girding the centre of the joints expand. They remain permanent during the whole of
the fixed stage, and give the stem of the Pentacrinoid its characteristic beaded appear-
ance. The terminal plate of the stem is formed on the same plan as the basals and
orals. It is developed as a simple round cribriform plate within the posterior extremity
of the pseudembryo ; and when this extremity becomes expanded into a disk of attach-
ment, it supports and forms the skeleton of the terminal sucker. Afterwards it becomes
thickened by irregularly deposited calcareous matter. The layer of soft tissue between
the calcareous disk and the point of attachment seems to be at length absorbed, and the
stem is permanently fixed by amorphous cement.
The first and second radial joints and the axillary radials. — Shortly after the fixing
of the Pentacrinoid and the opening of the cup, a third series of five plates make their
appearance as minute branching spiculse occupying the spaces left by the bevelling off
of the upper angles of the basal plates and the lower angles of the orals, thus forming
an intermediate series between the basals and orals, and alternating with them. The
spicula indicating the origin of these plates, the first radials, branch and extend in the
manner already described, till at length they form diamond-shaped films consisting of a
4 d 2
540
PEOFESSOE W. THOMSON ON THE EMBEYOGENT OF ANTEDON
single layer of cribriform calcified tissue. The plates shortly begin to thicken ; but
their mode of growth at once distinguishes them as fundamentally different in structure
from the basals and orals. Processes are sent inwards from the inner surface of the
superficial film as before ; but the added tissue is longitudinal and fasciculated, resem-
bling precisely in structure and mode of growth the inner cylinder of the joints of the
stem ; and, as in the case of the stem, tubular perforations are formed in it for the
passage of the sarcode-cords, which subsequently extend in like channels through the
joints of the arms and pinnules. The second radial joints and the radial axiilaries rapidly
succeed the first radials, and are developed nearly in the same way. They first appear
as horseshoe-shaped spicula, or imperfect rings, which have the same relation to the
joints which the stem-rings have to their included cylinders. The spicula soon become
filled up with lengthening fasciculated tissue ; the joints at this period are slightly grooved
longitudinally on their upper surfaces to accommodate the radial vessels.
The anal plate, the interradial plates, and the plates and spicula of the perisom. — Upon
the appearance of the second and third radial joints, the perisom between and somewhat
above two of the first radials rises into a rounded papilla, towards which a csecal process
of the digestive cavity is directed. On the outer side of this papilla a branching spicule
appears which rapidly extends into a round plate. This, the anal plate, grows, and
afterwards thickens precisely on the model of the basal and oral plates ; it contains none
of the fasciculated tissue proper to the radial system. The basal and oral plates, the
first and second radials, the radial axiilaries, and the anal plate seem to complete the
series of essential parts entering into the cup of the pentacrinoid. In one or two cases
however, I have observed about the time of the first appearance of the anal plate, a
series of five minute rounded plates developed interradially between the lower edges of
the oral plates and the upper edges of the basals. These interradial plates sometimes
remain permanent in the mature Antedon rosaceus, and they appear to be constantly
present in some species, as for instance in another and a rarer British form, Antedon
Milleri (Muller). They usually occur, finally, in groups of three or five. They are irre-
gular in form, and they resemble the anal plate in structure and mode of growth.
Simple and key-like spicula and small round cribriform plates are imbedded irregularly
in the perisom of the arms, often almost covering the second and third radial joints with
a dermal calcified layer, but never overlying the basal or oral plates of the body.
General remarks on the Skeleton. — The skeleton of the pentacrinoid is composed of
two systems of plates, which I shall term respectively the radial and the perisomatic
system, thoroughly distinct in their structure and mode of growth. The radial system
consists of the joints of the stem, the centro-dorsal plate, the radial plates, and the joints
of the arms (and subsequently of the pinnules). The perisomatic system includes the
basal and oral plates, the anal plate, the interradial plates, and any other plates or
spicula which may be developed in the perisom of the cup or disk. In the recent Pen -
tacrini, and in certain species of Antedon, the disk is paved or studded with plates
belonging to the perisomatic system, and a double series of like plates fringe the radial
EOSACEUS, LINCK (COMATULA EOSACEA OE LAMAECK).
541
and brachial grooves. The joints or plates of the radial system may be at once distin-
guished by their being chiefly made up of the peculiar fasciculated (or radial) tissue of
parallel rods which I have already described, and by their being perforated for the
lodgment of a sarcodic axis. At first each radial element appears to consist of two parts.
A stem-joint always commences with an annular spicule, within which the cylinder of
“radial” tissue seems to arise. An arm-joint begins with a crescentic spicule, and a
radial plate with an expanded single cribriform film. From the strong contrast which
these superficial portions present to the tissue which is afterwards developed beneath
them, I am inclined to refer the outer rings and films, even of the brachial joints and
radial plates, to the perisomatic system, and to regard the radial system of plates as
composed essentially of the “radial” tissue alone. The plates and joints of the radial
system are singularly uniform in their structure and arrangement throughout the whole
of the crinoidal series.
They seem to form, as it were, an essential skeleton whose constant general arrange-
ment stamps the order with its most important and prominent character. In the Pen-
tacrinoid the radial system of radial- and arm-joints supports the extensions of the radial
vessels, and the radial vessels with their oesophageal vascular ring clearly arise in con-
nexion with the disk, on the oral aspect of the animal. The radial plates arise at the
opposite or apical pole. The first portion of the radial system which appears is the stem.
When the sarcode-axis of the stem enters the cup, passing through the centro-dorsal
plate and between the lower edges of the basals, it splits into five threads which enter
the first radial plates, and after a somewhat singular distribution in the walls of the cup,
which is not apparent till a later stage, they follow out the growing arms, the arm-joints
being moulded round them as they extend. The perivisceral sac lies in the cleft formed
by the five radial branches of the stem. The plates of the perisomatic system commence
as simple cribriform films imbedded in the outer layer of the perisom, and thicken by a
repetition inwards of the same diffuse areolar tissue. They are essentially variable in
number and in arrangement ; most of the minor structural modifications throughout the
group depend upon the multiplication or suppression of plates of this series. Even in
the same species they are by no means constant. In Antedon rosaceus the perisom of
the disk is usually naked, but specimens from certain localities have well-defined groups
of perisomatic interradial plates developed in the angles between the radial axillaries,
and in some individuals rows of similar plates are imbedded along the margins of the
radial grooves in the perisom of the disk. The entire body of the Pentacrinoid is, at
first, while yet included within the pseudembryo and during its earliest fixed stage,
surrounded and enclosed by plates of the perisomatic system alone, and it is quite con-
ceiveable that plates belonging to this system may expand and multiply so as to form a
tessellated external skeleton to the mature animal, the radial system being entirely absent,
or represented only in the most rudimentary form. I believe that all the modifications
of the skeleton Avhich characterize the principal divisions of the Echinoderm subkingdom
will be found to depend mainly upon the relative development or suppression of the
radial and perisomatic systems of plates.
542
PROFESSOR W. THOMSON ON THE EMBRYOGENY OF ANTEDON
With reference to the form and position of the oral plates, Professor Allman has sug-
gested some interesting analogies between this transition stage of Antedon and the per-
manent condition of the fossil genera Haplocrinus, Coccocrinus, Stephanocrinus , and
Lageniocrinus. I thoroughly agree with Dr. Allman, that the oral plates of the Penta-
crinoid are in all probability homologous with valve-like plates surrounding the mouth
only in all crinoidal genera in which such plates occur. In Antedon rosaceus they dis-
appear during the later stages in the growth of the Pentacrinoid young, and in all known
species of the genus Antedon , even in those with a tessellated disk, they are wanting in
the mature form. In Pentacrinus ( Neocrinus ) asterias , (L.), the mature form to which
the fixed stage of Antedon is evidently most analogous, they are said to remain permanent.
The evidence on this point is as yet extremely defective. It rests entirely upon the
descriptions and sketches of M. Duchassaing *, which are sufficiently graphic, hut by no
means technically exact. In two nearly allied species, Pentacrinus {Neocrinus) Mulleri
(Oersted) and P. [N.) decorus (nob.), in both of which I have had an opportunity of
examining the perisom of the disk, the oral plates are totally absent.
Almost all Dr. Allman’s illustrations are necessarily taken from a small aberrant
family of Crinoids, the Haplocrinidse, of whose structure we know as yet very little. With
the exception of Stephanocrinus , which only doubtfully belongs to the group, all the
genera are Devonian, preceded by the peculiar Cystideans of the Upper Silurians, and
ushering in the carboniferous Blastoids.
Notwithstanding Professor Mullek’s discovery of rudimentary free arms, I cannot
help still leaning to the view that the triangular interradial valves in the Haplocrinidae
may, like the pointed upper tier of interradial plates in the Pentremites, surround not
only the mouth, but ovarian and anal openings ; a discussion of the homologies of the
fossil Crinoids is however foreign to the object of the present memoir.
The development of the assimilative and vascular systems, so far as it has been possible
to observe it at this early stage, has already been described in detail.
Explanation of the Plates.
PLATE XXIII.
Eig. 1. Portion of the ovary under slight pressure, showing ova in various stages of
development, X 40 linear.
Fig. 2, a-o. Ova in various stages, from the first appearance of the germinal spot 2, a
to the maturity of the egg 2, o, X 40 linear.
Eig. 3. Yelk-granules, X 120 linear.
* Quoted by M. de Kokixck, “ Recherehes sur les Crinoi'des du terrain Carbonifere de Belgique,” p. 53.
Brussels, 1854.
BOSACEUS, LIXCK (COMATULA EOSACEA OE LAMAECK).
543
Fig. 4. A group of parent cells containing vesicles of evolution, and forming a portion of
the tissue of the testis, X 40 linear.
Fig. 5, a-e. Parent cells with vesicles of evolution in various stages of development,
X40 linear.
Fig. 6, a-c. Mature vesicles of evolution containing spermatozoa, X 80 linear.
Fig. 7. Spermatozoa, X 120 linear.
Fig. 8. Egg shortly after impregnation, X 40 linear.
Figs. 9-13. The process of yelk segmentation, x40 linear.
Fig. 14, a-c. Further enlarged views of the earlier stages of yelk segmentation, showing
three groups of the “ direction vesicles,” X 80 linear.
PLATE XXIV.
Figs. 1-4. The development of the pseudembryo within the vitelline membrane, X 40
linear. In this case the development is somewhat abnormal.
Fig. 5. Dorsal aspect of the pseudembryo shortly after the rupture of the vitelline sac,
X 40 linear.
Fig. 6. Dorsal view of the pseudembryo a little more advanced, X.40 linear.
Fig. 7. Ventral aspect of the pseudembryo a little later, showing the pseudostome and
pseudoproct, and the rudiments of the cup plates of the embryo, X 40 linear.
Figs. 8, 9, 10. Ventral, dorsal, and lateral aspects of the pseudembryo shortly before the
disappearance of the ciliated bands, X 40 linear.
PLATE XXV.
Figs. 1-3. The pseudembryo losing its special organs of assimilation and locomotion and
passing into the “ pentacrinoid stage,” X40 linear.
PLATE XXVI.
Fig. 1. Pentacrinoid larva immediately after the complete separation of the oral valves,
expanded, X 40 linear.
Fig. 2. Pentacrinoid in the same stage, the cup closed, x40 linear, but afterwards
slightly reduced to suit the size of the plate.
Fig. 3. A portion of the oral disk of the same stage seen from above, in a state of com-
plete expansion : a, patent oral aperture bounded by a ring of contractile tissue,
and showing yellow richly ciliated granular folds, arranged somewhat spirally
on the walls of the digestive cavity; b, central ring of the radial vascular
system ; c, non-extensile tentacles in immediate connexion with the vascular
544 PEOFESSOE W. THOMSON ON THE EMBEYOGENY OF ANTEDON EOSACEHS.
ring, ten in number, and laid up in a state of complete expansion in pairs
against the inner surfaces of the oral valves f; d, first pair of extensile radial
tentacles ; e, azygous radial extensile tentacle leading out the growing arm to
its bifurcation, and giving off pairs of tentacles of the same series from its base.
X 40 linear.
PLATE XXVII.
Fig. 1. Pentacrinoid larva immediately before the expansion of the ventral disk: a,
centro-dorsal plate ; b, series of basal plates ; c, first radial plates ; d, second
radial joint; e, third radial ; f, first brachial joint; g, anal plate; h, stem-
joint ; k, cribriform plate supporting the disk of attachment ; l, granular vis-
ceral mass ; to, csecal process passing from the stomach towards the papilla
which indicates the position subsequently occupied by the anal tube ; n, oral
valve and plate. X 40 linear, slightly reduced.
Fig. 2. An example in a somewhat earlier stage, expanded, and showing the arrangement
of the non-extensile tentacles in connexion with the oral vascular ring, X 40
linear, considerably reduced.
Fig. 3. End of an extending arm further enlarged : a, 5, and c, first, second, and third
radial joints ; d, superficial spicules and small cribriform plates of the peri-
somatic system ; e, lenticular “ gland’”? ; f, radial vessel passing out on the arm
to terminate in the azygous extensile tentacle A, after giving off the second
paii’ of extensile tentacles k, Jc ; g, leaf and pair of tentacles of the non-extensile
tentacular system. X 40 linear.
Fig. 4. Pseudembryo uncompressed and observed by reflected light : a , pseudostome ;
b, pseudoproct ; c, c, c, c, ciliated bands. X 40 linear.
All the figures, except Plate XXVII. fig. 4, have been drawn from specimens under
slight pressure, and with a special view to the details of internal structure. The contour
has been thus in some cases to a certain extent lost, and the figures, especially those of
the pseudembryo, must be understood to represent individuals slightly flattened.
BvUb. Trouts. MDCXEEXVT FLate, JXXHI .
Ffol. Trams. WtCtQHTT.Flate, XT W
Eg 8.
Edwin l£.Wliains.JLS. sc.
Figl.
zgy-
T. ajcLnafc.rlfil
idv^M.Wli^cms.FLS. sc.
Bui. Trans. lUPfTOW VI**,. XXVT
3awm lOSSDiamsiXS. sc.
Hf 2.
Phub. Trans. MDCCCE^itoeXXM.
Edwin. M-WHa-ma TT. S.
[ 545 ]
X. On the Sextactic Points of a Plane Curve. By A. Cayley, F.B.S.
Received November 5, — Read December 22, 1864.
It is, in my memoir “ On the Conic of Five-pointic Contact at any point of a Plane
Curve”*', remarked that as in a plane curve there are certain singular points, viz. the
points of inflexion, where three consecutive points lie in a line, so there are singular
points where six consecutive points of the curve lie in a conic ; and such a singular
point is there termed a “sextactic point.” The memoir in question (here cited as
“ former memoir”) contains the theory of the sextactic points of a cubic curve ; but it is
only recently that I have succeeded in establishing the theory for a curve of the order m.
The result arrived at is that the number of sextactic points is =m(12m— 27), the points
in question being the intersections of the curve m with a curve of the order 12m— 27,
the equation of which is
(12m2-54m+57)H Jac. (U, H, ns)
+ (m— 2)(12m-27)H Jac. (U, H, Hg)
+40(m-2)2 Jac. (U, H, ^ )=0,
where U=0 is the equation of the given curve of the order m, H is the Hessian or
determinant formed with the second differential coefficients (a, h, c,f g , h) of U, and,
(91, 33, C, 4f, 1?) being the inverse coefficients (^[=5c— f2, &c.), then
Q=(g, as, e, f, <g, s*)2h,
*=(& 35, €, f, (3, m*rH, B,H, bJI)2;
and Jac. denotes the Jacobian or functional determinant, viz. "
Jac. (U, H, V) =
b„U, dyU, bzU
b,H, b^H, bsH
bffl', b/F, b;F
and Jac. (U. H, O) would of course denote the like derivative of (U, H, Q); the sub-
scripts (g, u) of O denote restrictions in regard to the differentiation of this function,
viz. treating Q as a function of U and H,
Q=(a, 33, c, jr, e, c'J'> 2/'> V,
if (a1, V , c',f\ g\ h1) are the second differential coefficients of H, then we have
b,Q=(b,&, . . X a’,..) (=b,Qg)
+ ( a, ..XbX ..) (=b,Og);
* Philosophical Transactions, vol. cxlix. (1859) pp. 371 — 400.
MDCCCLXV.
5 E
546 PEOEESSOE CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE.
viz. in +12g we consider as exempt from differentiation (a', b\ d,f',g', H) which depend
upon H, and in d,Qg we consider as exempt from differentiation ($, 33, C, Jf, <B, fl)
which depend upon U. We have similarly
^0=^125+^00, and d+l^+lg+c^Ou ;
and in like manner
Jac. (U, H, 0)= Jac. (U, H, Os)+ Jac. (U, H, Qg),
which explains the signification of the notations Jac. (U, H, Og), Jac. (U, H, Og).
The condition for a sextactic point is in the first instance obtained in a form involving
the arbitrary coefficients (A, (a, v) ; viz. we have an equation of the order 5 in (a, [a, v)
and of the order 12m— 22 in the coordinates (x, y, z ). But writing §-=lx-\-yjy-\-vz, by
successive transformations we throw out the factors S-2, 3-, S-, + thus arriving at a result
independent of (a, (a, v ) ; viz. this is the before-mentioned equation of the order 12m— 27.
The difficulty of the investigation consists in obtaining the transformations by means of
which the equation in its original form is thus divested of these irrelevant factors.
Article Nos. 1 to 6. — Investigation of the Condition for a Sextactic Point.
1. Following the course of investigation in my former memoir, I take (X, Y, Z) as
current coordinates, and I write
r=(*xx, y, z)m=o
for the equation of the given curve ; (x, y, z) are the coordinates of a particular point
on the given curve, viz. the ^sextactic point; and U, =(#$+ y-, z)m, is what T becomes
when ( x , y, z) are written in place of (X, Y, Z) : we have thus U = 0 as a condition
satisfied by the coordinates of the point in question.
2. Writing for shortness
DU =(XA,+Yd,+Zcg U,
D2U=(Xh;r+YB2/+ZB,)2U,
and taking n=«X+#Y+<?Z = 0 for the equation of an arbitrary line, the equation
D2U— UDU=0
is that of a conic having an ordinary (two-pointic) contact with the curve at the point
(x, y, z) ; and the coefficients of IT are in the former memoir determined so that the
contact may be a five-pointic one ; the value obtained for II is
n=f ^DH+ADU,
where
A = +(-3QH+4^).
3. This result was obtained by considering the coordinates of a point of the curve as
functions of a single arbitrary parameter, and taking
x-\-dx-\-\d‘lx-\-:^dzx-\-5xdix, y+ &c., z+ See.
PEOFESSOE CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CTTEVE. 547
for the coordinates of a point consecutive to ( x , ?/, z) ; for the present purpose we
must go a step further, and write for the coordinates
x dx -f - \d2x -f- -d?x -j- ~^dix -j- ^\od5x ,
y+dy +\d2y +±d3y +-^d4y +t h>d%
z-\-dz -\-\d?z -{-^d3z -\--^diz +xio dsz.
4. Hence if
B j = tfcrB* + dyby + dzbg, B 2 = d2xdv + d?yby -+- d?zb„ &c.,
we have, in addition to the equations
U=0,
B.U^O,
(B?+2B2)U=0,
(B?+3d1B2+S,)U=0,
(^i + SBfBa-f-dBjBg-f- 3B2-|-B4)Uz=0,
of my former memoir, the new equation
(B?+10^2+10^?B3 + 15B1^22+5B1B4+10B^3+^5)U=0,
and in addition to the equations, (P —ax-^-by-\-cz),
- (m-2)B?U+P.-|B2U=0
- ^[(m-l)^H3(m-2)^1b2]U+P.i(^-l-3B1B2)U+B1P.iB2U=0,
-*[(*»- l)(^t + ^A) + (m- 2)^,+ 3BS)]U
+P-^+6B^2+4aia3 + 3B-)U+B1P.i{B;+8B1^)U+iBiP.4drU=0,
giving in the first instance
P=2(m— 2),
B P=a diU
3 9?U
> -P _ 1 (at ■ + 69?92)U _ 4 a?U (9? + 39i92)U
a ~2 d?U 99?U 9?U
and leading ultimately to the before-mentioned value of n, we have the new equation
— wo [(m— 1)(B? + 10B?B2+ 10B2B3 +153^5) + (m— 2)(5dA + 10B2B3)]U
+ P • T2o(^i + 1 OB JB2+ 10BiB3 4- 15BjB2 +5BA+10BA) U
+ BtP.* (B}+ 6B2B2+ 4B1B3+ 3B2)U
+iB2P. 1 (B»+
+iBsP. | B?U=0.
5 e 2
548 PBOFESSOB CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CHEVE.
5. This may be written in the form
-2[(m-l)(B;+10B?9a+10B^3+15B1^)+(»i-2)(5BA+10BaB3)]U
+ P( B'+IOB^ + IOB^+ISB^ +5B1B4+10B3B3) U
+ 5b4P( b?+ 63$,+ 43,3,+ 3b22)U
+10b2P( b?+ 3BjB2)U
+10b3P( BJU)=0;
or putting for P its value, =2(m— 2), the equation becomes
- 2(b5+10b$2 + 10d$3+15b1b2)U
+ 53^(3*+ 6b?b2+ 43x3a+ 3b2 )U
+10b2P(b?+ 3b,b2)U
+10b3P.b2U=0;
or, as this may also be written,
2(bs+10b?b2+10b-2b3+15b1b2)U
+ 5b 4P . b4U + 10baP . b3U + 10b3P . b2U = 0.
6. But the equation
n = -| gDH + ADU,
which is an identity in regard to (X, Y, Z), gives
31P=lH3‘H’
a3P=t h3,H+A3sU,
3,P=tHaaH+A3,U;
and substituting these values, the foregoing equation becomes
2(b* + l0b2b2+10b2b3+15b1b2)U
+(5b4Ub1H+10b3Ub2H + 10b2Ub3H)f ^ + A.20b2Ub3U=0 ;
or putting for A its value, = g^g(— 3nH+4'vP), and multiplying by fH2 this is
9H2(b* + 10b?b2 + 10b?b3 + lSb^U
+15H (b4Ub^H+2b3Ub2H + 2b2Ub3H)
+ (-3QH + 4>P).10b2Ub3U=0,
which is, in its original or unreduced form, the condition for a sextactic point.
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OP A PLANE CURVE. 549
Article Nos. 7 & 8. — Notations and Remarks.
7. Writing, as in my former memoir, A, B, C for the first differential coefficients of U,
we have Bv— C^, Gx — Av, Ay — BX for the values of dx, dy , dz, and instead of the
symbol B used in my former memoir, I use indifferently the original symbol B15 or write
instead thereof B, to denote the resulting value
3i(=^)=(Bv-C^)B,+(CX-A»)^+(A|m(-Bx)B>,
and I remark here that for any function whatever O, we have
BO=
A , B , C
X , y , v
B,Q, B.Q, B.O
=Jac. (U, a, Q),
where §=Xx-\-yy-{-vz. I write, as in the former memoir,
®=(a, as, c, f, <g, p, »)*;
and also
V=(S3, 3S, C, S': <&, yj: dy, B,),
which new symbol V serves to express the functions IT, □ , occurring in the former
memoir; viz. we have n=2VO, □=2VH, so that the symbols 14, □ are not any
longer required.
8. I remark that the symbols B, V are each of them a linear function of (d*, B y, BJ,
with coefficients which are functions of the variables (x, y, z) ; and this being so, that
for any function 14 whatever, we have
B(vn)=(B.v)n+Bvn,
viz. in B(VI1) we operate with V on 14, thereby obtaining VII, and then with B on VII;
in (B.V)II we operate with B upon V in so far as V is a function of (x, y, z), thus
obtaining a new operating symbol B.V, a linear function of (B^,, B^, B*), and then
operate with B.V upon II; and lastly, in BVII, we simply multiply together B and V,
thus obtaining a new operating symbol BV of the form (Ba,, B^, B„)'2, and then operate
therewith on II ; it is clear that, as regards the last-mentioned mode of combination, the
symbols B and V are convertible, or BV = VB, that is, BVn = VdII.
It is to be observed throughout the memoir that the point ( . ) is used (as above
in B.V) when an operation is performed upon a symbol of operation as operand; the
mere apposition of two or more symbols of operation (as above in BV) denotes that the
symbols of operation are simply multiplied together; and when BV is followed by a
letter II denoting not a symbol of operation, but a mere function of the coordinates,
that is in an expression such as BVII, the resulting operation B V is performed upon II
as operand ; if instead of the single letter II we have a compound symbol such as HU
or HV^, so that the expression is BHU, BHV&, BVHU or BVHV3-, then it is to be
understood that it is merely the immediately following function H which is operated
upon by B or BV ; in the few instances where any ambiguity might arise a special
explanation is given.
550 PKOFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CTJRYE.
Article Nos. 9 to 11. — First Transformation.
9. We have, assuming always U=0, the following formulae (see post. Article Nos. 31
to 33):—
p;+io«d2+ioa$s+i6a1aBu
= { ( 2 7 m2 — 9 6 m -f- 8 1 ) Hd <E> -fi ( 1 7 m2 — 5 6 m 5 1 ) $>d H }
+ ^Iy4{(-Um-22)(d.V)H -(10m-18)c>VH}
d4Ud,H + 2d3Ud2H + 2d2Ud3H
=j^^{(-6m2+18m-12)H2d<P+(-17m2+60m-55)II<Pd(P}
+J~Ij4{(2m-2)H(d . V)H +(8m-16)BHVH}
(m— I)4 ^ ^^H},
d2Ud3TJ=-(^ir4HdH.
10. And by means of these the condition becomes
<^2tT2
0 = ^£Iy4{(153m2— 594m+549)HBO+(— 102m2+396m+366)OBH}
S3H
+ (^rT^{(-96m + 168)H(B . V)H+(-90m+162)HBVH+(120m-240)BHVH}
+7^Ip{9H2BQ-45HQBH+40^H},
being, as already remarked, of the degree 5 in the arbitrary coefficients (X, (m, v), and of
the order 12m— 22 in the coordinates (x, y, z).
11. But throwing out the factor ^2, and observing that in the first line the quadric
functions of m are each a numerical multiple of 51m2— 198m-|-183, the condition becomes
0= (51m2-198m+183)H2(3HdO-20hH)
{( — 96m-f 168)H2(d . V)H+(-90m+162)H2BVH + (120m-240)BHVH}
+&2{9H2BO-45HOBH-}-40^H}.
Article Nos 12 & 13. — Second transformation.
12. We effect this by means of the formula
(m— 2)(3HS$— 2C>BH) = — ^ Jac. (U, C>, H), .... (J)*
(J) here and elsewhere refers to the Jacobian Formula, see post, Article Nos. 34 & 35.
PROFESS OK CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE. 551
for substituting this value of (3Hb<E>— 205 H) the equation becomes divisible by SJ ;
and dividing out accordingly, the condition becomes
51m2 — 198m + 183
m — 2
H2 Jac. (U, O, H)
+(— 96m+l 6 8)H2(b . V)H+(-90m+162)H2bVH+(120m-240)HbHVH
+^(9H2b0-45Ii05H + 40'IbH)=0.
13. We have (see post, Article Nos. 36 to 40)
Jac. (U, $, H)=— (d. V)H;
and introducing also 5 . VH in place of b VII by means of the formula
bVH=b(VH)-(b.V)H,
the condition becomes
|5Irf-198», + l83 _(6m_6)|H8(3 _ y)H
+ (_90m+162)H2b(VH) +120(m-2)HbHVH
+a(9HabQ-45HQbH+4(WbH)=0,
or, as this may be written,
(45m2-180m+171)H2(b . V)H
+(— 90to + 162)(to— 2)H2b(VH)+12Q(m— 2)2HbHVH
+(m-2)S-(9H2bO-45HQbH+40^bH)=0.
Article Nos. 14 to 17 . — Third transformation.
14. We have the following formulae,
^Jac.(U, VH, H)— (5m— 11)BHVH+(3to— 6)Hb(VH)=0, . ... (J)
S-Jac. (U, V, H)H— (2m— 4 )bHVH+(3m— 6)H(b . V)H=0, . . . . (J)
in the latter of which, treating V as a function of the coordinates, we first form the
symbol Jac. (U, V, II), and then operating therewith on H, we have Jac. (U, V, H)H ;
these give
Jac. (U, VH, H),
H(3.V)H= f9HVH-3jA^jJac.(U,V , H)H;
and substituting these values, the resulting coefficient of HbHVH is
( 45m2-180m+171)f
+ (-90m+162)^=^
+ 120( m—2)2,
which is =0.
552 PROFESSOR CAYLEY. ON THE SEXTACTIC POINTS OE A PLANE CURVE.
15. Hence the condition will contain the factor 9, and throwing out this, and also the
constant factor 1 . it becomes
m— 2
(_ 15w»+60m— 57)HJac.(U, V , H)H
+(30m-54)(m-2) HJac.(U, VH, H)
+(m-2)2(9H2BQ-45HQBH+40^H)=0.
16. We have
BJ(VH)=p..V)H+B#VH,
viz. in (B,*. V)H, treating V as a function of ( x , y, z ) we operate upon it with B* to
obtain the new symbol B* . V, and with this we operate on H ; in BitV we simply mul-
tiply together the symbols B*. and V, giving a new symbol of the form (B2, B^, BaB„)
which then operates on H. We have the like values of By (VH) and B2(VH); and
thence also
Jac. (U, VH, H)= Jac. (U, V, H)H+ Jac. (U, VH, H),
viz. in the determinant Jac. (U, V, H) the second line corresponding to V is B*. V,
Bj, . V, Bs . V (V being the operand) ; and the Jacobian thus obtained is a symbol which
operates on H giving Jac. (U, V, H)H ; and in the determinant Jac. (U, VH, H) the
second line is B,rVH, By VH, BSVH (V being simply multiplied by B*, B^, B. respectively).
17. Substituting, the condition becomes
(— 15m2 + 60m— 57) HJac.(U, V, H)H
-f(30m-54)(m-2){H Jac. (U, V, H)H+ Jac. (U, VH, H)}
+ (m—2)2 {9H2BO-54HOBH + 40^BH}=0,
or, what is the same thing,
(15m2-54m+51)H Jac. (U, V , H)H
-f (30m-54)(m-2)H Jac. (U, VH, H)
+(m-2)2{9H2BO-45HOBH-f40^BH} = 0.
Article Nos. 18 to 27. — Fourth transformation, and final form of the condition fora
Sextactic Point.
18. I write
(5m-12)QBH-(3m-6)HBG=9- Jac. (U, 12, H) (J)
OBH+ HB12= B(QH),
and, introducing for convenience the new symbol W,
-50BII+ HBO=W,
5m- 12, —(3m— 6), 9 Jac. (U, O, H)
1 , 1 , B.12H
-5 , 1 , W
= 0,
so that
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CTJRYE. 553
or what is the same thing,
(8m-18)W + 6&Jac. (U, O, H)+(10m-18)b(QH)=0,
we have
o — Q
W=H50-50BH=i^f-9^Jac. (U, Q, H)—
19. We have also
(8m-18)TdH-(3m-6)Hd*-SJac. (U, H)=0, (J)
that is
=4^9aJaC'(U’'5'’ H)+“H^
and thence
9HW+40^dH
= 9H2BO-45HOBH+40^BH
= -9Ji^r H5(QH) + 6-2^-)H3M'
+4^=9 {-27H Jac.(U, a, H) + 40 Jac. (U, % H)}.
20. The condition thus becomes
(15m2-54m-f51) (4m-9)H Jac. (U, V , H)H
+6(5m-9)(m-2)(4m-9)HJac. (U, VH, H)
+ 3(m-2){-3(5m-9)(m-2)Hb(aH)-|-20(m-2)2Hb^}
-f (m— 2)2 — 27H Jac. (U, Q, H)+40Jac.(U, % H)} = 0,
which for shortness I represent by
3HH-|-(m— 2)2 —2 TIT Jac. (U, Q, H)+40Jac. (U, % H)}=0,
so that we have
11= (5m2— 18m+17)(4m— 9)Jac.(U, V , H)H
+2(5m-9)(m-2)(4m-9) Jac. (U, VH, H)
+(m— 2){ — 3(5m— 9)(m— 2)d(QH)+20(m— 2)2S'^r}.
21. Write
*,=(a', 35', C', 0, WXA, B, C)2,
where (A, B, C) are as before the first differential coefficients of U, and (cl, V, c’,f, cj, hi)
being the second differential coefficients of H, (£f, 15', C', Jf, 0, If)') are the inverse
coefficients, viz., Q^b'c'—f'2, See. We have
— (m— l)2BTr1=(3m— 6)(3?w— 7)b(OH)— (3m— 7)2B\P> [see post, Nos. 41 to 46),
that is
(3m-6)b(OH)=(3m-7)b^-|^^B^„
5 p
MDCCCLXV.
554 PEOEESSOE CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CUEVE.
and thence
11= (5m2— 18m+17)(4m— 9) Jac. (U, V , H)H
-j-2(5m-9)(m-2)(4m-9) Jac. (U, VH, H)
+(m_2)|(5rn2-18m+17)B^+(m~3^yr—
22. Now
*=(& 35, €, jr, <B, 1IA', B', C')2, %=(%, 33', €', f, <&, fc'*A, B, C)2,
and writing for shortness
E'F = (B0, . .JA, B‘, C')2, F'F =(a, . -IA, B', C'^B^', B$', BC'),
E^1=(Ba', . oca, b, c)2, F^^car, . oca, b, cxaa, bis , bc ),
(we might, in a notation above explained, write E'F=B'vP'h, F'4r=^B'4ru, and in like
manner ET'^B'^u, FSEr1=^BM' g), then we have
d^=E^+2F>p, B^r1=E^1+2F^1.
We have moreover
Jac. (U, VH, H) =-^Et7 E'F,, 1 post, Nos. 47 to 50.
Jac. (U, V , H)H=— E'F , J post, Nos. 51 to 53.
23. The just-mentioned formuke give
II = -(5m2-18m+17)(4m-9)E'F
— 2(5m— 9)(m— 2)(4m— 9) 3” FM^
+(m— 2)(5m2— 18m-F17)(E'vF +2FTr )
that is
+
(5m— 9) (m— l)2(m — 2)
3m — 7
(E^1+2F^1),
n = -(3m-7)(5m2-18m+17) E'F
+2(m— 2)(5m2— 18m+17) FT'1
(5m-9)(m-l)2(m-2)
■*" 3m- 7 1
2(m — l)(m — 2) (3m— 8) (5m— 9) _ -
3m— 7 * V|
or, as this may also be written,
(3m— 7)U=— (5m2— 18m-f-17){— 2(m— 1)( m— 2)FTr1 -f (3m— 7)2E4/ }
— (5m— 9)(m— 2) { (m-l)(3m-8)F'F1+(3m-7)(3m-8)F^-( m-l)2E«
+(25m2-103m+106)(m-2){ -( m-l)F^+ (3m-7)F^ }•
PEOFESSOE CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CUEVE. 555
24. But recollecting that
Q=(a, 33, G, 4T, fcX&« Bf, S,)2H
=(0, 33, C, #, 6, $X< y, d, 2 f, 2</, 2Af),
and putting
EO=(3g, ...J (=3QS),
fo=( a, ...x^', ...) (=aOtO,
we have,jpos£, Nos. 41 to 46,
— 2(m — l)(m— 2) F% +(3m-7)2E^ =(3m-6)(3m-7)HEO
(m-l)(3m-8)F^1+(3m-7)(3m-8)F^-( m-l)2E^1=(3m-6)(3w-7)HFO
— iim~ l)F^i+ (3m— 7)FF - = (3m— 7)OBH,
and the foregoing equation becomes
(3m-7)U = -(5m2-18m+17)(3m-6) (3m-7)HEO
-(5m- 9)(m— 2)(3m— 6) (3m-7)HFO
+ ( m- 2)(25m2— 103m— 106)(3m— 7)Oc)H.
25. But we have
^Jac.(U, H, Oh)— (3m— 6)HEO + (2m— 4)OhH=0, . . . . (J)
^ Jac.(U, H, Op)-(3m-6)HFO+(3m-6)ObH=0, . . . . (J)
that is
3(m-2)HEQ=2(m-2)QdH+&Jac. (U, H, Oh),
3(m-2)HFO=(3m-8)QhH+& Jac. (U, H, Op),
and we thus obtain
n=-(5m2-18m+17){2(m-2)QhH+^Jac. (U, H, Oh)}
— (5m— 9)(m— 2) {(3m-8)OdH+S Jac. (U, H, Op)}
+(25m2— 103m+106)(m— 2)OhH,
where the coefficient of (m— 2)OdH is
— (10m2— 36m+34)
— (5m— 9)(3m— 8)
-j-(25m2— 103m+106),
which is —0. Hence
H = -(5m2-18m+17)^Jac. (U, H, Op)
— (5m— 9)(m— 2) ^Jac.(U, H, Op).
26. Substituting this in the equation
3HH+(m— 2)2{ — 27H Jac. (U, O, H)+40 Jac. (U, % H)}=0,
the result contains the factor and, throwing this out, the condition is
3H { — (5m2 18m+17) Jac. (U, H, OH)-(5m-9)(m-2) Jac. (U, H, Op)}
+ (m-2)2{27H Jac. (U, H, O)-40 Jac. (U, H, ¥)} = 0,
5 f 2
556 PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE,
or, as this may also be written,
-(15m2-54m+51)HJac.(U, H, Qh)-3(5w-9)(to-2)H Jac. (U, H, Qv)
+ 27(m-2)2 {H Jac. (U, H, Oh)+ H Jac. (U, H, 0<j)}
— 40(m— 2)2 Jac. (U, H, ¥ )=0.
27. Hence the condition finally is
(12m2-54m+57)H Jac.(U, H, Qfl)+(m-2)(12m-27)H Jac. (U, H, fiy)
— 40(m — 2)2 Jac. (U, H, ¥)=0,
or, as this may also be written,
-3(m-l)H Jac. (U, H, nH)+(m-2)(12m-27)H Jac. (U, H, H)
-40 (m-2)2 Jac. (U, H, ¥)=0,
viz. the sextactic points are the intersections of the curve m with the curve represented
by this equation; and observing that U, H, HH and 4" are of the orders m, 3m— 6,
8m— 18 respectively, the order of the curve is as above mentioned =12m— 27.
Article Nos. 28 to 30. — Application to a Cubic.
28. I have in my former memoir, No. 30, shown that for a cubic curve
Q=(a, 33, €, f, <8, ®X3„ 3J’H=-2S . U=0,
this implies Jac. (U, H, O)=0, and hence if one of the two Jacobians, Jac. (U, H, O^),
Jac. (U, H, Oh) vanish, the other will also vanish. Now, using the canonical form
U =x3+f+z3+6lxyz,
we have
0=(<3,. .1 a',...)
=(yz—l2x2 , zx—l2y2 , xy—l2z 2, l2yz—lx 2, Pzx—ly2 , l2xy—lz2X
x -3 1% -3 l2y, -3 1% (1+2 l3)x, (1+2 l3)y, (1 + 2 l3)z),
the development of which in fact gives the last-mentioned result. But applying this
formula to the calculation of Jac. (U, H, Qu), then disregarding numerical factors, we
have
d,Q ^{yz-Px2, . , . Pyz-lx 2, . , . X-3^2, 0, 0, (1+2Z3), 0, 0)
= — 3 12 (; yz-l2x 2)
+(1+2 P){l2yz-lx>)
= (-/+^2+2^)=SBaU;
and in like manner
and therefore
Jac. (U, H, Ou)=S Jac. (U, H, U)=0,
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE. 557
whence also
Jac. (U, H, Oh) = 0;
and the condition for a sextactic point assumes the more simple form,
Jac. (U, H, ¥) = 0.
29. Now (former memoir, No. 32) we have
*=(& 33, C, f, <3, B„H, B~H)2
= (l-j-8^3)2 (yzz3+zzxz+xzyz)
+(-9 n (x*+y>+zj
5^—20^) (xz+yz+zz)xyz
+(— 15Z2— 78Z5+12 la)xyz\
or observing that and xyz , and therefore the last three lines of the expression
of 'P are functions of U {=xz-\-yz+zz-\-§lxyz) and H(= — lz(xz-\-yZJrzz)-\-(l-\-2lz)xyz),
and consequently give rise to the term=0 in Jac. (U, H, 'P), we may write
*=(1 + 8 lz)2(yzzz+zzxz+x3y3).
30. We have then, disregarding a constant factor,
Jac. (U, H, SP)= Jac. (x3-iryz-\-zz, xyz, yzzz-\-zzxi-\-xzyz)
= *2> y\ *2
yz, zx, xy
^(tf+z3), y%z'+x3), z%^+y3)
= (y’—z‘)(z’'-x‘)(x’—y‘),
so that the sextactic points are the intersections of the curve
TJ=ixz-\-yz+zz+6lxyz=0,
with the curve
Article Nos. 31 to 33. — Proof of identities for the first transformation.
31. Calculation of (5J+105352+10^B3+15B152)U.
Writing B in place of D, we have (former memoir, No. 20)
But
former memoir,
Nos. 21 & 22 ;
— B2H =(3m 6)(^_7)ho_
(m-l)2
— B2H =
558 PEOFESSOB CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CTTEYE.
and thence *2
^jy4(18m2-66m+60)HO
+ (S?iy4(-10m+18)VH
+K?iy|(Q)!
whence operating on each side with Bn =5, we have
(3;+10a>3,+63';3J+12313*)U= j-4 ( 1 8 m! - 6 6m + 6 0 ) ( H3 41 + <63H )
+(^ir4(-10m+18)((3-v)H+9VH>
+(^ir3Q-
We have besides (see Appendix, Nos. 69 to 74),
3?3,U= pli)3{(3m-6)H3<I>+(-m+3)<l>SH}
3^U= (^?ip(-H3<I>+<I>3H);
and thence
(43;3,+33,3|)U= ~y3{(90m-21)H3®+(-m+9)®3H}
+ (^{-4(3.V)H>;
and adding this to the foregoing expression for
(h?+10B^2+6B^3 + 12B1B2)U,
we have
(d\ + lOBft, + 105253 + 155 £*) U=
^Ay,{(27m!-96TO+81)H3<I>+(17m2-56»i+51)<I>3H}
+ (^T)i {(-14m+22)(3 . V)H + (-10m+18)3V . H}
ci4
-J-7 — ~va5Q.
1 (to — l)4
32. Calculation of
54U51H+253U52H+252U53H.
PEOFESSOE CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CIJEVE. 559
We have
Cj.2 1 2-^
B4U=7-— ^ |B2H+B2H -jK® SVH,
4 6 J 1 m — 1 m — 1 5
B3U=t— — TTg BH,
3 (m—iy ’
b2u=
32
(m— l)2
H,
B2H=B2H,
3,H=i^T(-3»l+6)3<l>-<t.3H+ ^
for which values see Appendix , No. 58. And hence the expression sought for is
+ 2(m— 1)BHB2H
+2H((-3m+6)HB<b-$BH+S(B . V)H)},
which is
|(m— 1)3H3,H
+ (m-l)3H3"H
+ (-6m + 12)H!34i-3H<I>3H}
+(^{2H(3.V)H-13HVHi.
But we have, former memoir, Nos. 21 & 25,
B2H= — (---~6) Hd> - — VH,
m — 1 m — 1
so that the foregoing expression becomes
32
= (^ip{-(8m-16)MBH+pBHVH
(3m 6)(3m_?)H^H 6m_14 QBH
m— 1 1 m— 1 m— 1
- 3H$B XI - (6m - 1 2)H2d O }
+^i?{2H(3.V)H-f3HVH}.;
or finally
B4UB,H+2B3UB2H+2B2TJB3H
= (i3Tj4{(-6ms+18m-12)Hs3<I>+(-17m,H-60m-55)H4>3H}
+ ^=Ij-4{(2ro-2)H(3.V)H+(8m-16)3HVH}
(» • V)H,
560 PEOFESSOE CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CUEVE.
33. Calculation of B2UB3U.
This is
•S4
(m— l)4
HBH.
Article Nos. 34 & 35. — The Jacobian Formula.
34. In general, if P, Q, 14, S be functions of the degrees p, q, r, s respectively, we
have identically
pF,
qQ,
rE,
sS
= 0,
B„Q,
BJt,
BXS
V.
V*
V,
B,Q,
B*E,
B*S
or, what is the same thing,
pT Jac. (Q, E, S)-#Q Jac. (E, S, P)+rE Jac. (S, P, Q)-sS Jac. (P, Q, E) = 0.
Hence in particular if P=U, and assuming U=0, we have
— Jac. (E, S, U)+rE Jac. (S, U, Q)-sS Jac. (U, Q, E)=0.
If moreover Q=B, and therefore q—\, we have
— ^ Jac. (E, S, U)+rE Jac. (S, U, B)-sSJac. (U, a, E)=0;
or, as this may also be written,
— B Jac. (U, E, S)+rE Jac. (U, 3-, S)-sSJac. (U, 3, E)=0;
that is
—3 Jac. (U, E, S)4-rE3S-sSBE=0.
35. Particular cases are
(2 m— 4) <P3H— (3m — 6)HBO =3Jac. (U, O , H), ante, No. 12,
(5m-ll)VH3H-(3m-6)HB(VH)=3 Jac. (U, VJI, H), „ 14,
{2m— 4)V:BH-(3m-6)HB.V
(5m— 12) OBH— (3m— 6)HBO
(8m— 18) TBPI-(3m-6)HB¥
(2m- 4) OBH— (3m— 6)HEO
(3m- 8) OBH— (3m— 6)HFO
=3 Jac. (U, V
, H), „
55
=3 Jac. (U, 0
, H), „
18,
=3 Jac. (U, ¥
,H), „
19,
=3 Jac. (U,
, H), „
25,
=3 Jac. (U, Oh
,H), „
„
where it is to be observed that in the third of these formulae I have, in accordance with
the notation before employed, written B . V to denote the result of the operation B per-
formed on V as operand. I have also written V : BH to show that the operation V is
not to be performed on the following BH as an operand, but that it remains as an
unperformed operation. As regards the last two equations, it is to be remarked that
the demonstration in the last preceding number depends merely on the homogeneity of
the functions, and the orders of these functions : in the former of the two formulae, the
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CURVE. 561
differentiation of Q is performed upon Q. in regard to the coordinates (x, y, z) in so far
only as they enter through U, and O is therefore to be regarded as a function of the
order 2 m — 4 ; in the latter of the two formulae the differentiation is to be performed in
regard to the coordinates in so far only as they enter through H, and Q is therefore to
be regarded as a function of the order 3m— 8. The two formulae might also be written
(2m— 4)I2BH— (3m— 6)HBQh=S- Jac. (U, Qg, H),
(3m— 8)ObH— (3m— 6)HbO(j=^ Jac. (U, H) ;
and it may be noticed that, adding these together, we obtain the foregoing formula,
(5m-12)QBH-(3m-6)HBQ=3- Jac. (U, Q, H).
Artie1? Nos. 36 to 40. — Proof of equation (B .V)H=Jac.(U, H, O),
36. We have
used in the second transformation.
v=(g,.ocx,p>op„3„3,)
=(i».+Sa,+«8,, ®3,+;f3»+C3J>, p, >).
Also
B=(Bv — Ciw-)ba.+(C?i — Av)dy-l~(Afjti — Bx)B_
= XP -f- ftQ -f- vR,
if for a moment
P, Q, B=CB2,— BB*, AB,-CB,, Bdx—Adr
Hence
3.v=(px+Qfl+&).(aa,+©39+®3„ i3,+u3,+Jfa=, ga.+.fa.+cajex, p, ,),
viz. coefficient of X2
=P8dJf+P%d,+PGd„
and so for the other terms ; whence also in (B.V)H the coefficients of X2, &c. are
(pgB.+pfcB,+p«3jH, &c.
37. Again, in Jac. (U, H, <b), where <E>=(£1, 13, C, jf, (0, (*, v)2, the coefficients
of X2, &c. are Jac. (U, H, 91), &c. ; and hence the assumed equation
(B .V)IJ=Jac. (U, H, O),
in regard to the term in X2, is
(Pa3.+Pfc3f +M3.)H=Jac. (U, H, 3),
and we have
Jac. (U, H, 3)=
A , B , C
B,H, B^H, BZH
, B, ,
8
= [B.tH(CB,-BBJ+ByH(ABs-CB,)+B,H(BBx-AB,)]g[
=(B,H.P+B,H.Q+B,H.R)a;
5 G
MDCCCLXV.
562 PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE.
so that the equation is
P^H+Pl^H+P^JH
= Pg^H + Q^H + Kgb JH,
or, as this may be written,
[{Bd.-Cd,)^-(Ca#-AB,)a]BfH
+[{BB,-caje-(Aaf-BB#)sri^=o.
38. The coefficient of c^H is
=AB.a+BB.®-C &&+*#),
which, in virtue of the identity, post. No. 40,
^+^1+^=0,
is
=AA$+BBJj+Cd*<g.
And in like manner the coefficient of <3 .11
= -(A^+B^+C^),
so that the equation is
(A^^+BB,i|+CB^H-(A^a+B^+CB^)B,H=0.
39. But we have
9[a+^A+<§^=H,
%h+%b+®f= 0,
&g+W+®c=0’
or multiplying by x, y, z and adding,
(m-l)(91A+lB+(aC)=^H ;
(m-l)(m+l^+#c+A^+B^l+C^)=^H,
that is
(m-l)(A^+B^l + C^(g)=^H ;
and in like manner
(m- l)(Ad.a+Bd.fc + 05.0)= J&JH,
whence the equation in question. The terms in X2 are thus shown to be equal, and it
might in a similar manner be shown that the terms in p are equal ; the other terms will
then be equal, and we have therefore
(d . V)H= Jac. (U, H, $).
40. The identity
assumed in the course of the foregoing proof is easily proved. We have in fact
3,3+3 M+^=Wc-f)+^fg-ch)+^(fh-ig)
=i(d,c-<>,9)+c(d,b--d„l i)
+/(-23/+3,<,+9^)+5-(3/-3,S)+A(-V+3/),
PEOFESSOE CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CUEVE. 563
where the coefficients of A, c, f g , A separately vanish : we have of course the system
d,.(S + c^#+ d*C = 0.
Article Nos. 41 to 46. — Proof of identities for the fourth transformation.
41. Consider the coefficients (a, b, c, f g , h) and the inverse set (9L B, C, Jf, <S,
and the coefficients (a', V , d,f, g', h1), and the inverse set (91', B', C', 4f', (S', ?!)') ; then
we have identically
(a, . .Xff, y, zf(% l', . -X«, • •)-(&'> • -1^ +% • -)2
=(a', . .X^r, y, z)X<&, . .X«', • •)— (3, • .X«'®+%+^> • -)2>
where (91', . .fa, . .) and (91, . . \a!, . .) stand for
(3', as', C', J', (S', i'X«, b,c,2f,2g, 2h)
and
(a 3 , C , jr , @ , » Jo!, K c, 2 If, 2^, 2A>)
respectively.
42. Taking (a, b, c,f g, A), the second differential coefficients of a function U of the
order to, and in like manner (a', A', c',f, g', h1), the second differential coefficients of a
function U' of the order to', we have
to (to - 1)U . (91', . 0C&„ ch)2U' - (to - i)2(9T, . -X^,U , 3,U , BJJ )2
i)U' . (a, . oca., cg2u — (to' — i )2(9i , . .xa.u', a,u', bjj')2;
and in particular if U' be the Hessian of U, then to'=3to — 6.
43. Hence writing
Q =(3, . . X*« ^)2H, ^ =(91, . -X^H, ^H, B.H)2,
Q>=(a', • • X*.» ^)2U, ^=(91', . -X^U, 3,U, BSU)2,
we have
TO(TO-l)U01-(TO-l)2^1=(3TO-6)(3TO-7)Hn-(3TO-7)2^;
or if U=0, then
-(to - 1)2^=(3to- 6)(3to- 7)HQ-(3to-7)24';
whence also
— (to— l)2Blr1=(3TO— 6)(3to— 7)(HBO+OhH)— (3to— 7)2Blr,
which is the formula, ante No. 21.
44. Recurring to the original formula, since this is an actual identity, we may
operate on it with the differential symbol ~d on the three assumptions, —
1. ( a , b, c,f, g , A), (91, B, C, Jf, (S, H) are alone variable.
2. (i a /, A', c',/', y', A'), (91', B', (S', JT, (S', $?') are alone variable.
3. ( x , y, z) are alone variable.
5 g 2
564 PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CURVE.
We thus obtain
+(«, . .Jx, y, z)2(9f, . .Jda, . .)
— 2(9f, • .Jax+Tiy+gz, . .Xxba+ifbb+z^c, . .)
{a,..Jx,y, Jo,..)
-(d£T, . -Xax+hy+gz, . .)2
2 (a, . Jjr, y, zjdx, Sy, Sz)(9P, . •!«, . •)
.Xa%+hy+gz, . XaBar+ASy+ySs, .)
= (*,.. X*,y,
— (hgl, . .Xa'x+h'y+g'z, . .)2,
= (da',..X*, y, *)’(&.. X«', ..)
+(®', . -X#, y, ^)2(9[, . -X^a', . .)
— 2(91, . .Xa'x+h'y+g'z, . .Xxda'+ybti+z'dg', .
=2(a', . .Xx, y, zXdx, Sy, S*)(9k . -X«', • •)
-2(91, .Xdx+Ky+tfz, . •Xaftff+A'Sy+y'Sas,
45. If in these equations respectively we suppose as before that («, b, c,f, g, h) are the
second differential coefficients of a function U of the order m, and (a-, b1. c',f , g', hi)
the second differential coefficients of a function U7 of the order m'; and that (A, B, C),
(A', B', C') are the first differential coefficients of these functions respectively, then after
some easy reductions we have
(m-l)(m-2)SU(9f, . Ja, . .) = . .X</, . .)
+m(m— l)U(9f, . Jba, • •) — (m'— 1)2(S9L, . ^A', B', C')2,
— 2(m— l)(m— 2)(91', . ^A, B, CXSA, SB, SC)
m(m- 1)U(B9T, . .X«'» • •) = (m'-l)(m,-2)SU,(91, . .X«', . .)
— (m— 1)2(S9P, . .XA, B, C)2 +m'(m'-l)U'(9, • -X^< • •)
— 2 (m' — l)(m' — 2) (91, . .XA', B', C'XSA', SB', SC').
2(m-l)SU(91', . .Xa, . .) = 2(m'-l)SU'(& . .Jet, . .)
-2(m-l)(9f, . -XA, B, CXBA, SB, SC) -2(m'-l)(91, . -XA', B', C'X^A', SB, SC'),
equations which may be verified by remarking that their sum is
m(m— l){SU(9f, . -X®, • 0+U[(Sl', . OP®, . O+PS', • 0C«> • •)]}
— (m — l)a{S9L', • -XA, B, C)2+(&', . .XA, B, C^A, SB, SC)}=m'(m'-l) &c.,
viz., this is the derivative with S of the equation
m(m— 1)U(9P, . .X«, • . )-(m-l)2(! 9', . -XA, B, C)2=m'(m'-1) &c.
46. Taking now U'=H, and therefore m'=3m— 6 ; putting also U=0, SU=0, and
writing as before
E^B =(S91, . -XA', B', C')2,
FTr =(9(, . . XA', B', C'X^A', SB', SC'),
E¥‘=(Sa,J ..XA, B, C)2,
?%=(%', • . XA, B, CX^A, SB, SC),
EH =(S3, ..x«'> ••)>
m=(9, .. x^®'* • •)>
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CURVE. 565
then the three equations are
-2(m-l)(m-2)F^1=(3m-6)(3m-7)HEO-(3m-7)2E'F,
- (m - 1)2E^ = (3m-7)(3m - 8)OBH
+ (3m- 6)(3m— 7)HFO -2(3m-7)(3m- 8)F^,
-2(m-l)F^ =2(3m-7)QdH-2(3m-7)F%
whence, adding, we have
- (m— l)2(EJq + 2F'P1) = - (3m- 7)2(E^ + 2F*)
+(3m-6)(3m-7){OBH+H(EQ+FO)}
(that is
- (m- l)*d% = - (3m- 7)W + (3m- 6)(3m- 7)B . OH,
which is right).
And by linearly combining the three equations, we deduce
(3m— 6)(3m— 7)HEO=— 2(m— l)(m— 2) F'F, + (3m-7)2E*,
(3m— 7)OBH = -(m-1) F^+(3m-7) F*,
(3m- 6)(3m- 7)HFQ= (m- l)(3m- 8)F*~ + (3m- 7)(3m- 8)FF- (m-l)2E% ,
which are the formulae, ante, No. 24.
Article Nos. 47 to 50. — Proof of an identity used in the fourth transformation , viz.,
Jac. (U,VH,H)=-3,^Fi'1,
or say
Jac. (U, H, VH)= (ST, . .JA, B, CJdA, BB, BC).
47. We have
v=(0, • -IK t>, 3,. 9.)
=((& & ^ »), (fi, 33, JflA, (6, f, CB. OP- 9,. 3.) :
or, attending to the effect of the bar as denoting the exemption of the (91, . .) from dif-
ferentiation,
Jac. (U, H, VII) = (& % <£!*., [*, v) Jac. (U, H, BXH)
+0£b 33, 4fB, (a, v) Jac. (U, H, ByH)
+ (®, f, CB, h v) Jac. (U, H, B;H).
48. Now
Jac.(U, H, BxH)=^g Jac. (U, tfBxH+yByH+zB2H, BXH),
and the last-mentioned Jacobian is
=BXH Jac. (U, x, BxH)+ByH Jac. (U, y , BxH)-f B2H Jac. (U, 2, BXH)
+y Jac. (U, ByH, BxH)+z Jac. (U, B2H, BXH),
566 PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE.
where the second line is
= -y Jac. (U, B,H, d,H)-M Jac. (U, bsH, dJEI),
or writing (A', B', C') for the first differential coefficients and (a', V, c', f, g\ h!) for the
second differential coefficients of H, this is
=-y
■y
A, B, C
+z
A, B, C
a', h', g!
9\ /', o’
V, v, f
a', h', g’
= -*/(C', Jf', C'XA, B, C)+*«', 33', Jf'XA, B, C).
The first line is
A,
B,
C
A',
B',
C'
a'.
A',
9'
= A(B7/ - C'h') + B(C 'a' - Mg') + C(A'A' - B V),
or reducing by the formulae,
(3m— 7)(A', B', 0)=(a!x^h!y-\-g’z, tix+Vy+fz, g’x+fy+c’z),
this is
=sM-7 {H-®y+®z)+*{-tfy+®z)+c(-®y+f'*)\
=ii=7 {-?(«’. «'XA> B, C)+Z(»', S', Jf'XA, B, C)}.
Hence we have
Jac.(U, H, a„H)=3A6 (1+aMf) < -?(«'. JT. «PXA. B, C)+2(S', S', Jf'XA, B, C)}
=3^7 { C'XA, B, C) +z(®'3', Jf'XA, B, C) } ;
and in like manner
Jac. (U, H, B,H)=
3m — /
1
Jac. (U, H, 3,H)=^
49. And we thence have
{-*(£', W, C'XA, B, C)+4<g', Jf', C'XA, B, C)},
{-<!', 33', Jf'XA, B, C)+2/(a', 1', C'XA, B, C)}.
Jac. (U, H, VH)=^
(^51,CX^^,0 , Jf , (C, Jf,CX^> ^ v )
(9T, 1', C'XA, B, C), (!', 33', Jf'XA, B, C), (C', Jf', C'XA, B, C)
x , y z,
or multiplying the two sides by
H,
a, A, g
K i, f
9> f> 0
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CURVE. 567
the right hand side is
'3m— 7
which is
if for a moment
=H
3m — 7
HA ,
HjU, , Hv
X ,
Y , Z
i— 1)A,
(m-l)B, (m— 1)C.
x ,
V 1,
X, Y,
Z
A, B,
C,
x=(3', . ..XA, B, CX«, h, g),
Y=(3', ..XA, B, C
z =(3', • • XA, B, CX?,./, c).
50. Hence observing that these equations may be written
X=(9T, . . -XA, B, CXc>,.A, B,B, B,C),
Y=(sr, . . XA, B, CXB,A, B,B, B,C),
Z = (&', . . -XA, B, CXB2A, B,B, BgC),
and that we have
B =
A ,
f* »
Bz
A,
B,
c,
we obtain for H Jac. (U, H, V, H) the value
=H
m — 1
^7(a', . . OCA, B, CXBA, BB, BC),
or throwing out the factor H, we have the required result.
Article Nos. 51 to 53. — Proof of identity used in the fourth transformation , viz.,
Jac./U, V, H)H=-E^,
or say
Jac. (U, H, V)H=(B& . . -XA', B', C')2.
51. We have
V = (($, % v), (% IS, tffk, y, v), (<§, f, CX^, 0X^« ^ ^«)>
and thence
B . V =((B$, B Jh Ba(§X^ *), BJ6, BjfXA, (*> d*CX*> (*, V)J$« \ d«).
and
(3,. V)H=((3.a, 3,®, 3.©X^ f*> *)> (3.fe 3,4fXA, ,), (3,®, 3,#, 3,CX>-, f*. »)XA', B', O
568 PROFESSOE CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE.
with the like values for (c^ . V)H and (cL . V)H. And then
Jac. (U, H, V)H=
A , B , C
A' , B' C'
P..V)H, (3„.V)H,
in which the coefficient of A'2 is
=(cd,-Ba.xa> % aix, o;
or putting for shortness
(Cby-Bb2, AB2-C^„ B3,-Acy=(P, Q, R);
the coefficient is
im, m, p<ax*> ft, o-
52. We have
<3=(PA + Q^-f Rv),
and thence
coefficient A'2— d$=(P$, P$2, P(§X^> v)~ Q*3, R$X^ v\
which is
= /»{(ca,-Ba,)®-(aa.-cd#)a}
+» {(ca,-BB.)«-(Ba.-aB,)a},
where coefficient of p is
and coefficient of v is
so that
=- Aa,0-BB2l+cp£+a,£)
= -(A3,g+B3..i + C32©)=-^I*3,H,
= +(A3„a+B3,»+C3,®)=
coefficient A'!-3Sl=
53. And by forming in a similar manner the coefficients of the other terms, it appears
Jac. (U, H, V)H-(3a, . . -XA', B\ C')2
1
or since the determinant is
^(A'w+3'y+Gz)
A' ,
B' ,
G
,
(* »
V
a,H,
bj,H,
B,H.
A'', B', C'
, =0,
a , v
A', B\ G
we have the required equation,
Jac. (U, H, V)H=(B& . . -XA', B', C')2.
This completes the series of formulae used in the transformations of the condition for
the sextactic point.
PROFESSOR CAYLEY OFT THE SEXTACTIC POINTS OF A PLANE CURVE. 569
Appendix, Nos. 54 to 74.
For the sake of exhibiting in their proper connexion some of the formulae employed
in the foregoing first transformation of the condition for a sextactic point, I have
investigated them in the present Appendix, which however is numbered continuously
with the memoir.
54. The investigations of my former memoir and the present memoir have reference
to the operations
"bg-\-dy 'd!/-\-dz dz,
d2= d2xbx + d2ydy + d2zbz ,
d3 =d3xdx-\-d3yd2/-\-d3zdl!l,
&c.,
where if (A, B, C) are the first differential coefficients of a function U = (#]£#, y, z)m,
and X, (Jj, v are arbitrary constants, then we have
dx= Bv—Cp, dy=CX—Av, dz=A(i>—B\;
so that putting
b=(Bf— (»b, + (Cx-Avfiy + (A^ -
= A, B, C
^ , l* , v
a., a„ *tt
we have ch = cb The foregoing expressions of (dx, dy, dz) determine of course the
values of (d2x, d2y, d2z), (d3x, d3y, d3z ), &c., and it is throughout assumed that these
values are substituted in the symbols d2, b3, &c., so that dn =d, and d2, d3, &c.
denote each of them an operator such as Xbr + Yc^ + ZcL , where (X, Y, Z) are
functions of the coordinates; such operator, in so far as it is a function of the coor-
dinates, may therefore be made an operand, and be operated upon by itself or any
other like operator.
55. Taking (i a,b,c,f,g,h ) for the second differential coefficients of U, (£1, 33, C, Jf, (3, i?)
for the inverse coefficients, and FI for the Hessian, I write also
o> =(&... X*,^ V)\
v =(& . . 0Ca„ a„ a.),
□ =(&... xa« bj,
S3 =Kx-\-^y-\-vz^
Q=(a, ...xa« a„ bjh, =dh,
T=(a, ...X^H, 3,H, cLH)2,
T =(a, . . ."yjyidg— vbp, vbJ—Xdz, Xd^—yid^)2,
5 II
MDCCCLXV.
570 PEOFESSOE CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CUE YE.
and I notice that we have
ru=2d>, VU~H, □U=3H,
5 TO— 1 5 5
V^= O, V2U=Hd> , V.3 = 0 ,
the last of which is proved, post No. 65 ; the others are found without any difficulty.
56. I form the Table
3,11=0,
a;u=^U
1 TO— 1
_ TT toU , , .
S2U=s3T(-4>)
a;u=-=^r3<i>
1 TO— 1
$2
32
+
(TO- If
$2
(H),
+
s2
+
+
(to— l)2
32
(3H),
a1asu=o,
3;U=^(4-) +^(-H<K),
3^=-?^™+-^ VH,
2 TO— 1 TO — 1
and assuming U=0,
(^ip( i»+£vH),
VH
3?H=32H= — (3m ^){^Z 7) a
(to — l)2
(to— l)2
(3 W=OH jr= aHVH-^ *,
which are for the most part given in my former memoir ; the expressions for b2U, d3U,
which are not explicitly given, follow at once from the equations
(32+32)U=0, (B2+2B132+33)U=0;
those for chd3U, d2U, and d4U are new, but when the expressions for chd3U and B2U are
PROFESS OE CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CURVE. 571
known, that for d4U is at once found from the equation
(^+6B$1+4B13,+ 3a;+BJU=0.
57. Before going further, I remark that we have identically
(a, . .)>, y, z)\a , . .\yy— v(3, m—Xy, X^-yuf
— ax+hy+gz , hx+by+fz, gx+fy+cz 2
X , fo , v
“ P 7
= (91, • -Xxp — vp — y§)2,
(if for shortness j9=ax-^~Py-\-yz, §='kx-\-yjy-\-vz)
=
—2p&(8, . .J\, yj, *}>, P, V)
+V(%,..ja,p,yy.
58. If in this equation we take ( a , b, c,f, g, h) to be the second differential coefficients
of U, and write also (a, /3, y) = (dx, <3y, cL), the equation becomes
m{m— l)Ur — (m— 1)2B2= $(xbx-{-yby-\-zbzy‘
—2
+S2D,
which is a general equation for the transformation of B2(=df).
59. If with the two sides of this equation we operate on U, we obtain
m(m— l)UrU — (m— l)2d2U = m(m-l)ffiU
— 2(m— 1)WU
+^2DU;
and substituting the values
FU=2d>, VU=^tH, □U=3H,
we find the before-mentioned expression of h2U.
60. Operating with the two sides of the same equation on a function H of the order
mf, we find
m(m- l)UrH - (m- l)2b2H=
-2(m'-l)WH
+ S2DH;
and in particular if H is the Hessian, then writing m'=3m— 6, and putting U=0, we
find the before-mentioned expression for d2H.
61. But we may also from the general identical equation deduce the expression for
(dH)2. In fact taking H a function of the degree m' and writing
(*, 1 3, y)=(3xH, 3,H, bJE),
5 h 2
572 PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE.
we have
m(m-l)U(a, . vdxH-Xd,H, XdyH-{*dxH)2-(m-l)2(dH)2
=m'2$H2-2mMVII+^2(a, . 3yH, BZH)2;
and if H be the Hessian, then writing m'=3m— 6 and putting also U=0, we find the
before-mentioned expression for (bH)2.
62. Proof of equation
5.= -^l(*Uj5,+^)+^V.
We have
d2=B.d = {(Bv-C^)Bx+(Cx-A^+(A^-B^}.
(*(C3S-B3.) +MA3- C3.) + »(B3.- A3,)),
which is
=X(Od,-B^,)+KA^-CB#)+F(B'd#-A'af),
where
A'=BA=«(Bi/ — Q*)+A(Cx — Av)-\-g(A(jj — Bx)
=\(hC-gB)+p(gA-aC)+V(aB-hA),
with the like values for B' and C'. Substituting the values
(m— 1)(A, B, C )=(ax+hy+gz, hx+by+fz, gx+fy+cz),
we have
(m-l)A'=x((By-^+Kfy-^)+K€y-fz);
and similarly
(m— l)C'=x(i^:— %)+^(3S^— %y)+*($x— %),
and then
(w-l)(C'd,~B'B,)= \\_{%x-9iy)by
+^[(33^— Ifoy^y—a&z—tfxjb^
= x[<a, n, a;, a.)-a(aa.+ya,+*a.)]
+H>(®, 33, fx^, ^)-»(^.+y^+^.)]
+»W«, 4f, ^ a.)-®(*&,+yB,+*a.)]
= <8, ...B, /*, d*)— (& <^XX> v){^x-\-y^y+zbz)\
that is
(Bi-lXCra,-»a.)=aV-(a, ©, ex\ p, »)(*M-3«,+sa.), and so
(«i-i)(A^-aaj=yv-fli, 33, jrxx, & 0(*a.+ya,+*&.),
(j»-l)(Bfc.-A^)=*V-(«, jf, CXA, p, V){x-bx+ybs+z\);
whence
(m— l)d2=(X#+^-f^)V— (gl, . . . JX, v)2(#d,+^,+zdz)
»•= • -At ^,+^,+^)+Ai v.
or finally
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURYE. 573
63. This leads to the expression for d2U ; we have
~{m— l)2
-(^LTfp 3>V(ffBJ+yB9+zB,)
_l_ — yz .
' (m — l)sV ’
and operating herewith on U, we tind
b*u= 7(ot ili&V
2 [in- 1)2
2(to — 1)S
(to — l)2
ovu
+(^rrpV!U;
this is
VU=— H, V2U=HcJ>,
(to— l)2 ~(to— 1)
64. We have B,B2U=0, and thence
that is
(B^2+B1b3+B2)U=0,
B1B3U=-B^2U-522U;
or substituting the values of B2d2U and d2U, we find the value of d,d3U as given in the
Table. And then from the equation
(^+6B2d2+4dA+3BI+d4)U,
or
d4U= _(BJ + 6dft2 + 4d,d3 + 3B2)U,
we find the value of d4U, and the proof of the expressions in the Table is thus com-
pleted.
65. Proof of equation V.d = 0.
We have
v. b=v. ((b*-<»b, +(Cx-a*)b, +(a^-bx)b.)
=V . (A(pB„-iB,)+B(.B#-XB„) +CQb,-ttij)
= VA (pB.-iB,) + VB(jB,-xB,)+ VC(xB,-a.B,) ;
and then
VA=(g, ...£*■> (a, vja, h, g )=HX,
VB = (& ...IX, p, Oft B,/)=Hp,
VC=(a --.B, c)= H„;
or substituting these values, we have the equation in question.
574 PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CTJRYE.
66. Proof of expression for B3.
We have
V;
and thence operating on the two sides respectively with B1? =B, we have
s>= — Al { 3<I>(.'i3„+y3»4- zd,)+ <M . (xxl.+ij'd, + id,) }
+^T{aav+aa.v};
or since
B .(a;B*-{-?/Bi,-|-zB..)=B, B^=0,
this is
67. Proof of expression for B3H.
Operating with B3 upon H, we have at once
B3H = _3m-6 1 OBH+_JL (B .V)H.
3 m— 1 m— 1 1 m— 1 v '
The remainder of the present Appendix is preliminary, or relating to the investiga-
tion of the expressions for B^U and BiB3U, used ante. No. 31.
68. Proof of equation V2BU=OBH-HBO.
We have identically
that is
(a ..oo, ^ ...p„ A)!-[ca ...jx, ^ a,)]*
={abc— &c.)(a, . . .^vB,,— ^B*, XBS— vbx, [*bx— ^B^)2;
a>n-V2=Hr;
and then multiplying by B, and with the result operating on U, we find
Now
and thence
and observing that
OnBU— V2BTJ=HTBU.
□ u=(2, B„ BJ2U
=(& h, c, 2/, 2 g, 2 h);
□ BU = (9[, ...Jjba, B5, Be, 2B/, 2 By, 2BA) ;
*, /
9, /> c
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CURVE. 575
and thence that
dH=
d«, d^, d</
+
«, K g
+
«, h , g
K b, /
Zh, Zb, Zf
h, i , f
/ c
g, /, . *
Zg , d/, dc
=(sr, fc, «xa«, ty)+®, as, zb, y)+(®, jr, y dC)
=(9, . . .JZa, Zb, Zc, 2Zf, 2 Zg, 2Zh,
we see that
Moreover
and thence
that is
Hence the equation
becomes
that is,
□ dU=dH.
ru= (a, ...JiZ,-i*d., ...)2U
= a(bv2 -\-cp?—2f(v» )
-f J(cX2 +«i/2 —2gvk )
+ c(a[jj2 + hk2 — 2 likfjb)
+ 2 /*( —f x2 -\-gX(jj + AXf — ap )
+ /V ~ 9P* + % - ^ )
+ 27i( /A -\-gvgj—hv 2 — cX[a) ;
rdu= :.,)-du
= a^dS -J- c? — 2'fAvZf)
+&c.
= JV2(6dc+cd5 -2/d/)
+&c.
=(*a, dB, bc, zf, d®, d^xx, ^ ,)2,
rdu=dd>.
<bndU-V2dU=HrdU
<bdH- V2dU=Hdd>,
V2dU=d>dH-Hd$.
69. Proof of equation d1d2U=-7^:Yy2(OdH— IidO).
We have
^2= (m- i]2^2(^d,r +ydy + zZzy
— (to- i)2 ^(^df+ydj+sdJV
_i_— — V2-
T (m-l)2 ’
576 PEOEESSOE CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CUEVE.
and thence multiplying by B1? =5, and with the result operating upon U, we find
3^u=(^l(7-2)^3u-^a^vu+^sv»u.
But BU=0, and thence also V(BU)=0, that is (V .B)U + VBU = 0; moreover V . B=0,
and therefore (V. B)U=0, whence also VBU=0. Therefore
or substituting for BV2U its value =<I>BH — HB<1>, we have the required expression for
B^U.
70. Proof of equation B 2B3U = j~_ (( 3 m — 6)HB d> -f ( — m-f- 3)<1>BH) + ^3- { — (B . V)H[ .
We have
+ V,
and thence multiplying by B?=B2, and operating on U,
B^U^-^BWU- -J- $B3U + -^(B . V)B2U.
i 3 m— 1 m— 1 1 in — lv '
To reduce (B . V)B2U, we have
and since
B(VB2U)=VB3U+ (B . VB2)U
=VB3U + [(B . V)B2+ V(B . B2)]U
=VB3U + (B . V)B2U+2VBB2U,
multiplying by VB, and with the result operating on U, we obtain
VBB2U= - ■ <E> VBU+ ——7 V2BU ;
2 m — 1 1 m— 1
or since VBU=0, this is
VBB2U = -^-,V2BU.
Hence m~1
B(VB2U)=VB3U+(B . V)B2U+~ V2BU,
that is m
(B . V)B2U=B(VB2U)-VB3U-~ V2BU.
Substituting this value of (B . V)B2U, we find
B2B3U= -^Bd>B2U- --7 $B3U
m — 1 m— 1
(3(V3!U)— V3*U)
+p^)2(-2V"3U),
the three lines whereof are to be separately further reduced.
PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OE A PLANE CURVE. 577
71. For the first line we have
d2U= — d3U=-— ~VgBH,
and hence
(m — l)2
[m-lf
first line of BJB3U=^^((m-2)HB<l> + <I>BH).
{m— 1)
72. For the second line, we have
that is
V(B2U)=VB2U + 2(V .B)BU
=VB2U, since V . B=0, and therefore (V . B)BU=0 ;
V9>U=V(yU)=v(£Y$__|_sH)
or writing
this is
whence also
Similarly
=^(UVO+$VU)--^I?(^VH+2^HVa);
3
U=0, VU= — H, V^=<1>
’ m— 1 ’
{m — 2)5
VB2U=
(: m — l)2
Hd>—
s2
(m-iy
VH,
3(V3-U)=^A|(H3<I.+$3H)- ^B(VH).
VB3U=V(B3U)
mU
$2
fBO— , 3 so
m — I ( m — 1 y
BH
=^I(VU34>+UV(3<l>))-fS^Tp(a!V(3H)+2&Va3H);
or putting
U=0, VU= V&=<*>,
1 m— 1 ’ ’
and observing also that V(BH), = VBH+(V . B)H is equal to VBH, that is to BVH,
we obtain
V3>U= {-^I)i(mH34>-24.3H)-^i?BVH;
and then from the above value of B(VB2U), we find
B(V35TJ)-V3*U=^Tp(-2H34.+m4>BH)+(^~1(-3(VH)+BVH);
•&2
or observing that the term multiplied by ^m_^2 is = — (B . V)H, we find
second line of B2B3U=^Ip(-2HB<I>+m$BH)+ . V)H).
5 i
MDCCCLXV.
578 PROFESSOR CAYLEY ON THE SEXTACTIC POINTS OF A PLANE CURVE.
73. For the third line, substituting for V2dU its value =d>BH— Hdd>, we have
2$2
third line of d2d3U= — H<3<f>).
74. Hence, uniting the three lines, we have
3?3»U = ^Ays((m -2)H3<K+ 4>3H)
+ (^( -2H34.+
+ (^^53((2m-2)H34>+(-2m+2)4>aH),
and reducing, we have the above-mentioned value of d2c)3U.
C 579 ]
XI. A Description of some Fossil Plants , showing Structure , found in the Lower Coal-
seams of Lancashire and Yorkshire. By E. W. Binney, F.B.S.
Received May 12, — Read June 15, 1865.
Introductory Bernards.
Although great attention has been devoted to the collection of the fossil remains of
plants with which our coal-fields abound, the specimens are generally in very frag-
mentary and distorted conditions as they occur imbedded in the rocks in which they are
entombed ; but when they have been removed, cut into shape, and trimmed, and are seen
in cabinets, they are in a far worse condition. This is as to their external forms and
characters. When we come to examine their internal structure, and ascertain their true
nature, we find still greater difficulties, from the rarity of specimens at the same time
displaying both the external form and the internal structure of the original plant.
It is often very difficult to decide which is the outside, different parts of the stem
dividing and exposing varied surfaces which have been described as distinct genera of
plants.
The specimens were collected by myself, and taken out of the seams of coal just as
they occurred in the matrix in which they were found imbedded, by my own hands.
This enables me to speak with certainty as to the condition and locality in which they
were met with.
By the ingenuity of the late Mr. Nicol of Edinburgh, we were furnished with a
beautiful method of slicing specimens of fossil-wood so as to examine their internal
structure. The late Mr. Witham, assisted by Mr. Nicol, first applied this successfully,
and his work on the internal structure of fossil vegetables was published in 1833. In
describing his specimens, he notices one which he designated Anabathra pulcherrima.
This did not do much more than afford evidence of the internal vascular cylinder
arranged in radiating series, somewhat similar to that which had been found and
described by Messrs. Lindley and Hutton as occurring in Stigmaria fcoides, in their
third volume of the 4 Fossil Flora.’
In 1839 M. Adolphe Brongniart published his truly valuable memoir, “Observations
sur la structure interieure du Sigillaria elegans comparee a celle des Lepidodendron et
des Stigmaria et a celle des vegetaux vivants.” His specimen of Sigillaria elegans was
in very perfect preservation, and showed its external characters and internal structure in
every portion except the pith and a broad part of the plant intervening betwixt the
internal and external radiating cylinders. Up to this time nothing had been seen at
all to be compared to Brongni art’s specimen, and no savant could have been better
mdccclxv. 5 K
580
ME. E. W. BINNEY ON SOME LOWER-COAL-SEAM FOSSIL PLANTS.
selected to describe and illustrate it. His memoir will always be considered as one of
the most valuable ever contributed on the fossil flora of the Carboniferous period.
In 1849, August Joseph Corda published his ‘Beitrage zur Flora der Vorwelt,’ a
work of great labour and research. Amongst his numerous specimens, he describes and
illustrates one of Piploxylon cycadoideum, which, although not to be compared to
Brongxiaet’s specimen, still affords us valuable information, confirming some of that
author’s views rather than affording much more original information. All these last
three specimens Brongniart, in his ‘Tableau de vegetaux fossiles consideres sous le
point de vue de leur classification botanique et de leur distribution geologique,’ pub-
lished in 1849, classes as Dicotyledones gymnospermes under the family of Sigil-
larees; amongst other plants his Sigillaria elegans , Witham’s Anabathra , and Corda’s
Piploxylon.
In 1862 the writer published an account of specimens in the ‘ Quarterly Journal of
the Geological Society’ of that year, which confirmed the views of the three learned
authors above named as to Sigillaria and Piploxylon being allied plants ; he also showed
that their supposed pith or central axis was not composed of cellular tissue, but of
different sized vessels arranged without order, having their sides barred by transverse
striae like the internal vascular cylinders of Sigillaria and Lepidodendron. These speci-
mens were in very perfect preservation, and showed the external as well as the internal
characters of the plants.
All the above specimens were of comparatively small size, with the exception of that
described by Corda, which, although it showed the external characters in a decorticated
state, did not exhibit any outward cylinder of a plant allied to Sigillaria with large ribs
and deep furrows so commonly met with in our coal-fields, but rather to plants allied to
Sigillaria elegans and Lepidodendron.
In the present communication it is intended to describe some specimens of larger
size than those previously alluded to, and to endeavour to show that the Sigillaria vascu-
laris gradually passes as it grows older into ribbed and furrowed Sigillaria , and that
this singular plant not only possessed two woody cylinders, an internal one and an external
one, both increasing on their outsides at the same time, but likewise had a central axis
composed of hexagonal vessels, arranged without order, having all their sides marked
with transverse striae. Evidence will also be adduced to show that Sigillaria dichoto-
mized in its branches something like Lepidodendron, and that, as in the latter plant, a
Lepidostrobus was its fructification. The outer cylinder in large Sigillaria was com-
posed of thick-walled quadrangular tubes or utricles arranged in radiating series, and
exhibiting every appearance of having been as hard-wooded a tree as Pinites, but as yet
no disks or striae have been observed on the walls of the tubes. Stigmaria is now so
generally considered to be the root of Sigillaria, that it is scarcely necessary to bring
any further proof of this proposition ; but specimens will be described which will prove
by similarity of structure that the former is the root of the latter.
The chief specimens described in this memoir are eight in number, and were found
ME. E. W. BINNEY ON SOME LO WEE-COAL-SEAM EOSSIL PLANTS.
581
by me in the lower divisions of the Lancashire and Yorkshire coal-measures imbedded
in calcareous nodules occurring in seams of coal.
Specimen No. 1, .from the first-named district, is from the same locality as the Trigo-
nocarjjon, described by Dr. J. D. Hooker, F.R.S., and myself, in a memoir “ On the
Structure of certain Limestone Nodules enclosed in seams of Bituminous Coal, with a
Description of some Trigonocarpons contained therein” *, and the other seven specimens
are from the same seam of coal in the lowercoal-measures as that in which the specimens
described in a paper entitled “On some Fossil Plants, showing Structure, from the Lower
Coal-measures of Lancashire ”f, were met with, but from a different locality.
The position of the seams of coal in which the fossil-woods were found in the carbo-
niferous series will be shown by the following sections of the lower coal-measures.
In Lancashire.
yds.
ft.
in.
In Yorkshire.
yds.
ft.
in.
1
1
0
Beeston or Silkstone seam
. . 2
0
0
69
0
0
Strata
0
0
0
0
3
Eoyds or Black seam
. 0
2
10
Strata
57
0
0
Strata
. . 38
0
0
Seam
0
0
6
Better Bed seam
. . 0
1
4
Strata
45
0
0
Strata
. . 51
0
0
Upper flagstone (Upholland)
50
0
0
Upper Flagstone (Elland)
. . 40
0
0
Strata
20
0
0
Strata
. . 40
0
0
Seam (90 yards)
0
0
5
Seam (90 yards)
. . 0
0
6
Strata
20
0
0
Strata
.. 56
0
0
Seam (40 yards)
0
1
6
Seam (40 yards)
. . 0
1
0
Strata
64
0
0
Strata
.. 39
0
0
«*Upper Foot seam (Dog Hill)
0
1
2
Strata
15
0
0
^Gannister seam
1
0
0
* -^Halifax Hard seam
. . 0
2
3
Strata
13
0
0
Strata
.. 14
0
0
Lower Foot seam (Qnarlton)
0
2
0
Middle seam
. . 0
0
11
Strata
17
0
0
Strata
.. 24
0
0
Bassy seam (New Mills)
0
2
6
Soft seam
.. 0
1
6
Strata
40
0
0
Strata
.. 56
0
0
Seam
0
0
10
Strata
10
0
0
Sand or Featheredge seam
0
2
0
Sand seam . ,
. 0
o
4
Eough Eock of Lancashire (Upper Millstone
of Geological Survey)
20
0
0
Upper Millstone of Phillips (Halifax) . .
. . 36
0
0
Strata (Eochdale or Lower Flags)
120
0
0
Strata (Lower Flagstone)
72
0
0
*Seam
0
0
6
Little seam
. . 0
0
3
Strata
2
0
0
Seam
0
0
10
Strata
14
0
0
Seam
0
1
3
Upper Millstone of Lancashire.
In the Lancashire coal-field all the seams of coal, from the forty yards downwards, have
at places afforded the Amculojpecten and other marine shells in their roofs of black shale,
and these latter strata generally contain calcareous nodules. The nodules in the seams
of coal commonly known by the name of Bullions have chiefly been found in the beds
marked #, ##, and ### in Lancashire, whilst in Yorkshire they have as yet been only
observed in the Halifax Hard seam marked
* Philosophical Transactions, 1855, p. 149.
t Quarterly Journal of the Geological Society of London for May 1862, p. 106.
5 K 2
582
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM EOSSIL PLANTS.
Description of No. 1 Specimen.
The first specimen intended to be described in this communication is from the thin
seam of coal marked * in the lower coal-measures of Lancashire arranged in the vertical
section previously given, and is from the same mine from which the specimens described
by Dr. Hooker and myself were obtained. It was found associated with Calamodendron,
Halonia, Sigillaria, Lepulodendron , Stigmaria, Trigonocarpon, Lycopodites, Lepidostrobus ,
Medullosa , and other genera of plants not yet determined in the order of relative
abundance in which they have been just named.
A portion of a similar specimen of fossil-wood obtained by me from the same locality,
on analysis* gave
Carbonate of lime . .
.... 76-66
Carbonate of magnesia
.... 12-87
Sesquioxide of iron
.... 4-95
Sulphate of iron . . .
. . . . 0-73
Carbonaceous matter .
.... 4-95
The stratum lying immediately above the seam of coal in which the specimen occurred,
generally termed the roof, was composed of black shale containing large calcareous
nodules, and for a distance of about 2 feet 6 inches upwards was one entire mass of fossil
shells of the genera Goniatites, Orthoceratites, Aviculopecten, and Posidonia.
The beds in the vicinity of the coal occurred in the following order, namely,
yds. ft. in.
1. Black shale with nodules containing fossil shells 0 2 6
2. Upper seam of coal enclosing the nodules full of fossil-wood .006
3. Fire-clay floor full of Stigmaria 020
4. Clay and rock 200
5. Lower seam of coal 0010
6. Fire-clay full of Stigmaria.
The fossil-wood occurred in circular, lenticular, and elongated and flattened oval-
shaped nodules, varying from an inch to a foot in diameter, the round and uncompressed
specimens being in general small, whilst the flattened ones were nearly always of a large
size. No fossil shells were met with in the nodules found in the coal itself, although, as
previously stated, they were very abundant
in the nodules found in the roof of the
seam, which there rarely contained any
remains of plants. The large nodules of
10 to 12 inches in diameter, when they
occurred, swelled out the seam of coal
both above and below as in the annexed
woodcut, fig. 1.
* Por this analysis I am indebted to the kindness of Mr. Hermann.
Fig. 1.
MR. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
583
Specimen No. 1 was originally, when first found, 6 inches in length by 7 in breadth,
and of an oval form. Its exterior surface was not very well preserved, the outer bark
coming off with the matrix of coal in which it was imbedded, but the inner bark
showed an irregularly fluted surface marked with fine longitudinal striee.
In Plate XXX. fig. 1, one half of the specimen is represented. The middle portion
of the specimen in transverse section shows a central axis, marked a, having its inner
portion, somewhat compressed, and composed of hexagonal-shaped vessels showing
all their sides marked with transverse strise, arranged without order. Around this axis
is a cylinder of hexagonal vessels, 5, arranged in radiating series of considerably less
size than those of the central axis, but having all their sides similarly marked with
transverse strife, and increasing in size as they extend from the centre to the circum-
ference. On the outside of this radiating cylinder is a part of the specimen not show-
ing much structure, but apparently having been once composed of coarse cellular tissue.
Beyond this is another zone, for the most part now consisting of mineral matter, chiefly
crystallized carbonate of lime, sometimes affording evidence of structure in the form of
tubes or elongated utricles arranged in radiating series, and forming an outer cylinder
in the plant.
Figs. 2 & 3 show longitudinal and tangential sections of the natural size, taken from
the lower and upper portions of fig. 1.
Fig. 4 shows a part of the transverse section, magnified five diameters, where the com-
mencement of the wredge-shaped masses are seen with convex ends adjoining the central
axis, and parted by medullary rays or bundles extending from the centre to the circum-
ference, and probably communicating with the leaves on the outside of the plant.
Figs. 5 & 6 show longitudinal and tangential sections of a little more than one half
of the specimen, magnified five diameters, the latter displaying the oval-shaped bundles
of vessels traversing the internal cylinder of the plant from the centre to the circum
ference.
This specimen is evidently of the same genus as that described by Witham, and
obtained by him from Allenbank in Berwickshire, from the mountain-limestone series,
and named Andbathra pulcherrima , although in a much more perfect state of preserva-
tion *. My specimen, however, does not show a pith of cellular tissue, it being rather
imperfect in that part; but it distinctly confirms Witham’s opinion as to the occur-
rence of medullary rays or bundles dividing the woody cylinder; and it appears to be
nearly identical in structure with Diploxylon cycadoideum of Cord a f, with which it will
be classed.
This specimen is not in so perfect a state of preservation as those fossil-woods intended
to he hereinafter described in this communication, especially as regards its central and
external parts ; but it certainly differs from them in having a larger mass of scalariform
* On the Internal Structure of Eossil Vegetables found in the Carboniferous and Oolitic Districts of Great
Britain, by H. T. M. Witham, E.G.S. &c. Edinburgh, 1833.
f Beitrage zur Flora der Vorwelt, Taf x.
584
MR. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
tissue composing the central axis, and having the inner portions of the wedge-shaped
bundles forming the internal radiating cylinder of a convex shape as they approach the
central axis, somewhat like those represented by Brongniart in his SigiUaria elegans ,
and still more resembling those described by Corda in Diploxylon cycadoideum* ; but my
specimen shows within those convex bundles a broad zone of scalariform tissue arranged
without order and marked with transverse striae.
It has been assumed, both by Corda and Brongniart, that Diploxylon had a pith
composed of cellular tissue, surrounded by a medullary sheath of hexagonal vessels
arranged without order, barred on all their sides with transverse striae. My specimen is
evidently more complete in structure than those of the last-named authors, or even that
which Witham himself described ; but although it shows the so-called medullary sheath
in a very perfect state, there is nothing to indicate the former existence of a pith of cel-
lular tissue. All the specimens examined by Witham, Corda, and Brongmart appear
to have had their central axes removed altogether and replaced by mineral matter,
or else only showing slight traces of their structure ; and these authors appear to have
inferred the former existence of a pith of cellular tissue, rather than to have had any
direct evidence of it in the specimens of Anabathra , Diploxylon, and SigiUaria respect-
ively figured by them. Every collector of coal-plants is well aware of the blank space
so generally left in the above fossil plants as well as in the roots Stigmariae. It is quite
true that a little disarrangement of the scalariform vessels ( a ') in the specimen is seen ;
but the part which remains undisturbed shows that the whole of the central axis was
formerly composed of hexagonal vessels arranged without order, having all their sides
marked with transverse striae and not of cellular tissue. This view is confirmed by
another and more perfect specimen of Anabathra in my cabinet, and enables me to
speak with positive certainty, and to show that these three plants had a similar struc-
ture in the central axes to the specimens of SigiUaria vascularis described by me in my
paper published in the Quarterly Journal of the Geological Society.
My specimen clearly proves the existence of medullary rays or bundles traversing
the internal woody cylinder, which originate on the outside of the central axis ; and it
appears to me pretty certain that Corda’s specimen of Diploxylon cycadoideum , if tan-
gential sections had been made and carefully examined, would have done the same.
The exterior of the specimen is not in a very complete state of preservation, but it
seems to have been covered by irregular ribs and furrows, with slight indications of
remains of the cicatrices of leaf-scars. Its marked character, as previously alluded to,
is the great space occupied by the central axis. This is of much larger size than in
either the SigiUaria vascularis or the specimens intended to be next described.
The lunette-shaped ends of the wedge-like bundles of the inner woody cylinder bear
some resemblance to the form of the same parts of the SigiUaria elegans of Brongniart,
but much more to those of Corda’s Diploxylon cycadoideum , with which it appears to
be identical.
* See M. Beongniakt’s paper on SigiUaria, previously quoted.
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM EOSSIL PLANTS.
585
The lunette-shaped extremities of the inner radiating cylinder of Diploxylo7i cycadoi-
deum , as well as those in my specimen, remind us of a similar arrangement shown to
occur in Stigmaria by Dr. Hooker, in plate 2. fig. 14*; and they appear to differ from
those found in Sigillaria vascularis in not being divided from the central axis by a
distinct line of demarcation, just as the same author’s Stigmaria fig. 5 differs from
fig. 14. The exterior of the inner radiating cylinder of the former plant is more free
and open, and not so sharp and compact as that of the latter plant. Indeed, from
structure alone, it would appear probable that the first-named Stigmaria was the root
of Diploxylon, whilst the last one was the root of Sigillaria vascularis.
As Brongniart has preferred Corda’s name of Diploxylon to Anabatlira , and as the
former is a more expressive generic term in my opinion, probably it is better to adopt
it, and accordingly the specimen has been denominated Diploxylon cycadoideum.
Description of Specimens Nos. 2, 3, 4, 5, 6, 7, & 8.
The second specimen intended to be described in this memoir is from a small seam of
coal about 2. feet in thickness in the lower coal-measures, marked ## in the vertical section
previously given, and from the same seam that the specimens of Sigillaria vascularis ,
described by me in the paper published in the Quarterly Journal of the Geological
Society previously quoted, came from, although from a different locality. This specimen,
as well as those numbered respectively 3, 4, 5, 6, & 7, all came from the Halifax Hard
seam, the Gannister coal, at South Owram near Halifax. It was found associated with
Sigillaria , Stigmaria , Lepidodendron , Calamodendron, Ealonia , Diploxylon, Lepidostrobus,
and Trigonocarpon, and other fossil plants not well determined in the order of relative
abundance in which they have been just named.
A portion of one of the specimens, a large Sigillaria , gave, on analysis f,
Sulphates of potash and soda T62
Carbonate of lime 45*61
Carbonate of magnesia 26*91
Bisulphide of iron 1T65
Oxides of iron 13*578
Silica 0-23
Moisture 0*402
The stratum found lying immediately above the seam of coal in which the nodules
occurred was composed of black shale containing large calcareous concretions, and for
about 18 inches was one entire mass of fossil shells of the genera Aviculopecten , Gonia-
tites , Orthoceratites, and Posidonia.
* Memoirs of the Geological Survey of Great Britain, vol. ii. part 1.
t Eor this analysis I am indebted to the kindness of Dr. E. Angus Smith, F.E.S., 'who had it done in his
laboratory by Mr. Browning.
586
ME. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
The beds occurred in the following (descending) order, namely,
ft. in.
1. Black shale full of fossil shells and containing calcareous concretions 1 6
2. Halifax Hard seam with the nodules containing the fossil plants . 2 0
3. Floor of fire-clay and Gannister, full of Stigmaria jicoides .
The fossil-wood is found in nodules dispersed throughout the coal, some being spherical
and others elongated and flattened ovals, varying in size from the bulk of a common pea
to 8 and 10 inches in diameter. In some portions of the seam of coal the nodules are
so numerous as to render it utterly useless, and they will occur over a space of several
acres, and then for the most part disappear and again occur as numerous as ever. For
a distance of from twenty-five to thirty miles the nodules occur in this seam of coal in
more or less abundance, but always containing the same plants. Fossil shells are rarely
met with in the nodules found in the coal, but they occur abundantly in the large cal-
careous concretions found in the roof of the mine, and are there associated with JDadoxy-
lon containing Sternbergia-Yrihs, which plant has not yet been noticed in the coal, and
Lepidostrobus. So far as my experience extends, the nodules in the coal are always found
associated with the occurrence of fossil shells in the roof, and may probably be owing
to the presence of mineral matter held in solution in water, and precipitated upon or
aggregated around certain centres in the mass of the vegetable matter now forming coal
before the bituminization of such vegetables took place. No doubt such nodules con-
tain a fair sample of the plants of which the seams of coal in which they are found
was formed, and their calcification was most probably chiefly due to the abundance
of shells afterwards accumulated in the soft mud now forming the shale overlying
the coal.
The specimen illustrated in Plate XXXI. fig. 1, is of an irregular oval shape, 1 foot
3 inches in circumference, 7 inches across its major, and 3J inches across its minor axis.
When first discovered it was 8 inches in length, and only a fragment of a much larger
stem. The light-coloured disk in the middle, about an inch in diameter, shows the
central axis and the internal radiating cylinder of woody tissue, while the indistinct
radiating lines towards the circumference indicate the outer cylinder, formed of thick-
walled tubes or utricles of quadrangular form arranged in wedge-shaped masses divided
by coarse muriform tissue, increasing in the opposite direction as to their size that the
wedge-shaped masses do : all of the natural size.
Fig. 2 shows the outside appearance of the specimen marked with fine longitudinal
striae, irregular ribs and furrows, and some cicatrices of leaf-scars, which would induce
most collectors of coal-plants to class it with a decorticated specimen of Sigillaria. It
most resembles Sigillaria organum. The bark of a portion of the specimen remains
attached to it in the form of coal, that is united to the matrix of the seam in which the
fossil was found imbedded. The reverse side of the specimen does not show the character
so distinctly.
Here we have a Stigmaria-like woody cylinder, with a central axis composed of barred
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM FOSSIL PLANTS.
587
vessels arranged without order, found in the inside of a stem of Sigillaria in such
a position as it existed in the living plant. It is not a solitary instance, but one of
more than fifty specimens exhibiting similar characters which have come under my
observation.
In Plate XXXII. fig. 1, is represented the light-coloured disk previously alluded to,
and shown in Plate XXXI. of the natural size, but here magnified 5 diameters, exhi-
biting the central axis composed of hexagonal vessels arranged without order, of several
sizes, those in the middle being smaller and becoming larger towards the outside, where
they come in contact with the internal radiating cylinder b , and then again diminishing
in size. This latter was no doubt cylindrical, like the stem of the plant, but both parts
in the process of petrification have been altered by pressure to their present forms. It
consists of a broad cylinder ( b ) of about an inch in diameter, composed of parallel elon-
gated tetragonal or hexagonal tubes of equal diameter throughout for the greater part
of their length, obtuse and rounded at either extremity, and everywhere marked with
crowded parallel lines which are free or anastomosing all over the surface. The tubes
towards the axis are of the smallest diameter ; they gradually enlarge towards the circum-
ference, where the largest are situated, though bundles of smaller tubes occasionally occur
among the larger. This cylinder, which for convenience may be called the internal
woody system of the plant, is divided into elongated wedge-shaped masses, pointed at
their posterior or inner extremity, and parted by fine medullary rays of various breadths,
some much narrower than the diameter of the tubes, others considerably broader, but
none are conspicuous to the naked eye, except towards the outer circumference in some
rare instances.
Fig. 2 represents a transverse section of the central axis and the commencement of
the internal radiating cylinder, magnified 12 diameters. The hexagonal vessels in the
centre and at the circumference, where they come in contact with the internal radiating
cylinder, are smaller in size than those seen in the other parts of the axis. The dark line
across the axis, as well as the dark space in the centre, both seem to be the result of a
disarrangement of the tubes during the process of mineralization, as similar appearances
have not been observed in many other specimens examined by me, which in those parts
are in a more perfect state of preservation. The dark and sharp line separating the
vessels of the central axis from those of the internal radiating cylinder does not permit
us to clearly see the origin of the medullary rays or bundles which undoubtedly traverse
the latter.
Fig. 3 represents a longitudinal section taken on the right-hand side of the specimen,
and extending across the whole of the internal radiating cylinder through the central
axis, the intermediate space between the internal radiating cylinder and the outer
cylinder, and the external radiating cylinder to the outside of the stem, magnified 4 dia-
meters : a a showing the smaller barred vessels of the central axis, having some ( a / a!)
which appear to have been disarranged ; b b the internal radiating cylinder of larger
barred vessels ; c the space occupied by lax cellular tissue traversed by bundles of vessels ;
and d the external radiating cylinder, consisting of elongated tubes or utricles arranged
mdccclxv. 5 L
588
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM EOSSIL PLANTS.
in radiating series diverging from certain circular openings, and divided by masses of
muriform tissue which contain the medullary rays or bundles.
Fig. 4 is a tangential section of the same parts of the specimen as lastly described,
magnified 4 diameters ; V V showing the medullary rays or bundles traversing the inner
radiating cylinder, and d' d' those traversing the outer radiating cylinder.
Plate XXXIII. fig. 1 is a longitudinal section of a portion of the same specimen,
exhibiting the central axis* and the inner radiating cylinder, magnified 15 diameters.
Fig. 2 shows several of the vessels of the central axis as they would be if they were
not ground away in the operations of slicing and polishing, magnified 45 times.
Fig. 3 is a tangential section of the inner radiating cylinder, b showing the barred
vessels, and b" the medullary rays or bundles, magnified 15 diameters.
Figs. 4 & 5, longitudinal and tangential sections of the same specimens, showing the
structure of the outer radiating cylinder, d denoting the tubes or elongated utricles of
which it is composed, and d' the medullary rays or bundles which traverse it, magnified
10 diameters.
Plate XXXIV. fig. 1 represents a transverse section of a ribbed and furrowed stem
(No. 3), displaying similar cicatrices to that of No. 2 given in Plate XXXI., and having a
like central axis, as well as like internal and external radiating cylinders and other parts,
magnified 2 diameters. It is given for the purpose of more distinctly showing the
tubes or elongated utricles, d , and the fusiform openings formed of very open muriform
tissue, d' enclosing the medullary rays or bundles which traverse the external radiating
cylinder. This it does in a very marked manner: magnified 20 diameters.
In Plate XXXV. figs. 1, 2 & 3 (Nos. 4, 5 & 6), are shown the exteriors of three central
axes separated from large ribbed and furrowed stems, in every respect similar to those
described in Plate XXXI. and Plate XXXIV., and such as might easily be taken for small
Calamites, magnified diameters. Fig. 4 (No. 7) shows the outside of the internal
woody cylinder of a Stigmaria with ribbed and furrowed characters, resembling those
shown on the outsides of the central axes lastly described, also magnified 2| diameters.
The first three specimens, Nos. 4, 5 & 6, are from the Halifax Hard seam of coal at
South Owram, but No. 7 is from the Wigan Five Feet Mine, a seam in the middle coal-
measures.
The tangential sections which show the medullary rays or bundles that traverse the
inner and outer radiating cylinders, afford clear evidence of the different appearance of the
bundles marked b " in Plate XXXIII. fig. 3, from those in Plate XXXIV. fig. 2 marked d'.
Specimens Nos. 2 & 3 bear considerable resemblance to the Sigillaria elegans of
Brongniart, with respect to their internal radiating cylinder and the medullary rays
or bundles which traverse it, assuming that such vessels come from the outside of the
central axis, and not from the exterior of the internal radiating cylinder, as that distin-
* In the Plate the small tubes a' a" appear to be divided by septae. This is certainly the case in one slice,
but in another of the same specimen these septae are not seen, but small barred vessels appear in their places,
so the former may probably be due to the direction of the slice being cut along the dark line which traverses
the central axis, as shown in Plate XXXII. figs. 1 & 2.
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM FOSSIL PLANTS.
589
guished savant supposed. Certainly there is no evidence in my specimens to support
the latter view. A great many specimens have been broken up and destroyed for the
purpose of examining the inner radiating cylinder, and in every case medullary rays or
bundles were found traversing it, just as you find in the same part of Stigmaria. On
the outside of the inner cylinder, at the extreme part of the zone of coarse and lax
cellular tissue which bounds it, are some circular openings, from which spring the wedge-
shaped masses of quadrangular, tubular, or elongated utricles which form the outer
radiating cylinder. The lax cellular tissue has nearly always been displaced and dis-
arranged in the process of mineralization, and sometimes the outer radiating cylinder
and the circular orifices connected with it have been pushed towards the inner cylinder.
This may have been the case in Brongniart’s specimen, and caused him to suppose
that the medullary rays or bundles originated only on the outside, and were not joined
to those which traversed the inner cylinder. So far as my large specimens show, there
were medullary rays which had their origin next the central axis, passed through the
inner cylinder, and after traversing the zone of lax cellular tissue outside the latter,
apparently communicated with similar rays or bundles of vessels of much larger size,
which are always found traversing the outer radiating cylinder, and then went on to the
leaves on the outside of the stem.
In Brongniart’s specimen the tubes or elongated utricles composing the outer
radiating cylinder appear to have been far more delicate in structure than the thick-
walled tubes in specimens Nos. 2 & 3*, but probably not more so than might be
expected from the difference in size of the plants, my specimens being about twelve
times as large as his, and in all probability so much older individuals. The tubes in
mine might easily be mistaken for similar tubes in Pinites if their size and the thickness
of their walls were merely considered, and no notice were taken of the discigerous
characters of that genus. In my specimens no disks have as yet been observed on the
walls of the tubes, nor have they afforded any evidence of the transverse striae which
characterize the tubes of the central axis and internal radiating cylinder. It is possible
that these markings may have once existed on the walls of the tubes, and been after-
wards obliterated during the process of mineralization. The thick walls of the tubes
in my specimens often exhibit circular dots of a yellow colour, bearing some resem-
blance to coloured disks. The absence of the disks is the only reason for distinguishing
the outer tissue in my specimens from the woody portion of Pinites , and this absence
of disks is sometimes found to prevail on the walls of the tubes of small specimens of
Dadoxylon , which are found with piths of Sternbergia inside them.
The late Mr. J. E. Bowman, F.G.S., in his paper on the Fossil Trees discovered on the
line of the Bolton Railway, near Manchester f, and which were in all probability old
Sigillarice , at considerable length endeavoured to prove that they were hard-wooded
solid timber trees, in opposition to the then common opinion that they were soft or
* In the longitudinal section represented in the Plates these tubes are made more delicate than they appear
in the specimens.
f Transactions of the Manchester Geological Society, vol. i. p. 112.
5 l 2
590
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM FOSSIL PLANTS.
hollow stems. In my company that author first saw the trees, and he then observed
to me that the roots of those fossil trees clearly indicated by their great size and strength
that the trees when living had heavy tops.
In all the numerous specimens of large Sigillaria which have come under my obser-
vation, the outer radiating cylinder shows more or less evidence of lines of growth, and
is generally divided into rectangular masses parted by straight lines of sparry matter,
just as a piece of oak taken out of a peat bog and dried does at the present day. This
similarity in divisional structure strongly supports the view of the late Mr. Bowman as
to Sigillaria being a hard-wooded tree, which has lately been revived by Dr. Dawson,
F.R.S., in his paper “ On the Vegetable Structures of Coal,” who says, “ I am even
inclined to suspect that some of the described specimens of Conifers of the coal may be
the woody axes of large Sigillaria?, or at least approaching quite as nearly to those
plants as to modern Conifers”*. All the large specimens of fossil trees found in seams
of coal give evidence of having been subject to considerable pressure when in a soft
state, and this might also cause the divisional lines above alluded to, without resorting
to a process like that which takes place in drying bog oak.
In the specimens Nos. 2 & 3 the outer radiating cylinders are nearly an inch and
a half in breadth of thick-walled tubes, or elongated utricles arranged in radiating
series, and diverging from a circular opening, while in Brongniart’s Sigillaria elegans
the outer radiating cylinder was not more than -j^th of that breadth. Probably my
specimens may not prove to be of the same species as that of the celebrated Autun
specimen, still they may be of the same genus, although of considerably greater age.
But they have the greatest resemblance to the Sigillaria vascularis described by me in
a paper read before the Geological Society, and printed in its Journalf. All the speci-
mens described in that communication, as well as those in the present one, were obtained
by me from the same seam of coal, but at different places, still the two, namely, the
large ribbed and furrowed specimens and the small rhomboidal scarred stems, are
always found associated together, and they can be traced gradually passing from one into
the other. These facts, when taken in connexion with the similarity of structure in the
central axis, the internal radiating cylinder, the space filled with lax cellular tissue
between the latter and the outer radiating cylinder diverging from circular openings,
clearly prove that the smaller specimen is but the young branch of the older stem, No. 2.
It is true that the earlier authors who have written on these plants, would scarcely have
admitted a ribbed and furrowed Sigillaria to have been so intimately connected with
a rhomboidal scarred plant, but it is now generally allowed that such differences in
external characters would afford no grounds for ignoring the structural similarity of the
specimens. Undoubtedly the small Sigillaria vascularis was part of a branching stem ;
for in my cabinet there is a specimen clearly showing two internal radiating cylinders just
at the point where the branches dichotomized, as shown in woodcut (fig. 2), so often met
with in Lepidodendron.
* Quarterly Journal of the Geological Society, vol. xv. p. 636.
f Quarterly Journal of the Geological Society for May 1862.
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM EOSSIL PLANTS.
591
Whatever evidence Dr. Dawson had for supposing a large Fig. 2.
Sigillaria to have been possessed of the obtuse top and the
flat main roots, as shown in his restored specimen, figured in
vol. xv. of the ‘ Quarterly Journal of the Geological Society,’
it is impossible to say, but certainly in all the numerous
specimens which have come under my observation nothing
has occurred to warrant me in supposing Sigillaria to be such a plant. Everything
has led me to believe that the leaves and branches, and probably the fructification of
Sigillaria, would prove to be very analogous to those of Lepidodendron.
In order to show the identity in structure of specimens 2 & 3 with Sigillaria vascu-
laris, previously described by me*, in Plate XXXV. fig. 5 is a specimen of Sigillaria
vascularis from the same pit and seam of coal as the larger specimen No. 2, showing a
transverse section, and fig. 6 exhibiting the external characters of the plant, part being
covered with its bark, and part being decorticated, magnified 4 diameters.
On comparing this specimen with those figured in Plates XXXI., XXXII., XXXIII.,
and XXXIV., the greatest difference is seen in the external characters of the stems ;
but, as before stated, these can be traced from a regular rhomboidal scar, like that of the
Lepidodendron, to the irregularly ribbed and furrowed Sigillaria. When we examine
their internal structure it is found that their central axes are alike. The internal
radiating cylinders are the same in both, making allowance for the greater age of the
large specimen, each having been undoubtedly exogenous. The space on the outside of
the inner radiating cylinder, filled with lax tissue and traversed by medullary bundles,
is well marked and defined in the smaller specimen, much more so than in the larger
one ; but neither show the nature and position of these bundles, which will be noticed
more at large in a specimen from a different locality hereinafter described. The outer
boundary of this space in the small specimen is marked by a well-defined line of carbon-
aceous matter. The coarse cellular tissue on the outside of the latter, with the circular
openings from which proceed the bundles of vessels traversing the outer zone of tubes or
elongated utricles in radiating series, forming the outer cylinder, are the same in both.
The term tubes, or elongated utricles, has been previously employed to denote the
structure of the outer cylinder. The inner portion of this zone is made up of what
appears to be coarse cellular tissue. This gradually elongates as it proceeds outwards
into utricles, which in their turn pass into tubes of a quadrangular form, of which
Fig. 3.
the outer part of the cylinder is composed. The
accompanying woodcut (fig. 3) represents a lon-
gitudinal section of No. 8, described in Plate
XXXV. figs. 5 & 6. From this it is seen that
the elongated utricles are more prominent and
numerous in the small specimens, whilst in the
large specimens, like those in Plates XXXIII.
& XXXIV., the tubes are chiefly seen.
* Quarterly Journal of tlie Geological Society for May 1862, p. 106.
592
ME. E. W. BINNEY ON SOME LOWER-COAL-SEAM FOSSIL PLANTS.
The outer cylinder seems to surround the band of lax cellular tissue enveloping the
inner cylinder, and appears something in the nature of a pith to it. The inner cylinder
no doubt increased on its outside by encroaching on the zone of lax cellular tissue, as
may be proved by comparing a young with an old specimen, No. 8 with No. 2.
This outer zone of pseudo-wood increased externally like the inner cylinder, as is
evident on comparing the younger with the older plant, the walls of the tubes of the
latter being stronger, as might be expected to be the case ; and in both we have the
singular phenomenon of a tree increasing externally in two different zones at the same
time.
As to the internal radiating cylinders described as occurring in the Diploxylon and
Sigillaria , given in this communication, they are evidently like two different Stigmaria-
cylinders, which afford no structure in their central axes, exactly resembling those
figured by Dr. Hooker in his paper on Stigmaria jicoides printed in the ‘ Memoirs of
the Geological Survey of Great Britain’*, in plate 2. figs. 14 & 5. In the latter we
have the wedge-form masses of wood of a lunette shape running into the central axis,
whilst in the former we have them separated by a sharp and well-defined line from the
central axis. The identity of structure between Sigillaria and Diploxylon and these
two Stigmarice is further proved by some specimens which have lately come under my
notice.
After the researches of Dr. Lindley, Professor Goeppert, Mr. Prestwich, Dr. Hooker
and others, it really seemed that we had obtained almost a complete knowledge of the
internal structure of Stigmaria. It is true that only Goeppert had seen the isolated
bundles in the pith ; all the specimens of the other observers having been imperfect in
that portion of the plant, and not giving indication of structure there f. In my own
researches it has rarely fallen to my lot to meet with a Stigmaria showing any structure
in the central axis, even where the small stems of Sigillaria vascularis , affording all the
structure in that part, are in great abundance.
Many years since, after an examination of a great number of specimens of Stigmaria
in my collection, it occurred to me that an outer radiating cylinder would ultimately be
discovered. In my remarks on Stigmaria % is the following passage: — “That part
of Stigmaria which intervened between the vascular axis and the bark appears to have
consisted of two different kinds of cellular tissue. These, in most cases, have been
unfortunately destroyed, so that we cannot positively know their true nature ; but they
appear to be of different characters, for there generally appears to be a well-marked
division. This is often shown in specimens composed of clay ironstone which have not
been flattened, and the boundary line is generally about a quarter of an inch from the
outside of the specimen. Most probably the outer part of the zone has been composed
of stronger tissue than the inner one, as is the case with well-preserved specimens of
* Memoirs of the Geological Survey of Great Britain, vol. ii. part 1.
t I liave written to Professor Goeppert for the purpose of obtaining further information as to the pith of
this specimen, but I have not been successful in my endeavour.
£ Quarterly Journal of the Geological Society, vol. iv. part 1. p. 20.
ME. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
593
Lepidodendron.” It is singular that Drs. Lindley and Hooker, as well as such acute
observers as Brongniart and Goeppert, had not noticed this line of division, but it was
no doubt owing to the imperfect specimens which they had examined. After the
discovery of the outer radiating cylinder by Witham in Lepidodendron , and the same
arrangement in Sigillaria by Brongniart, it was to be expected that such outer radia-
ting cylinder would be found to occur in Stigmaria , if it were the root of Sigillaria.
After an inspection of a great number of specimens, the cabinet of Mr. Bussell, of
Chapel Hall, Airdrie, has afforded me four or five distinct specimens which give clear
evidence of the existence of this outer radiating cylinder in Stigmaria. They are all in
clay ironstone, and have not been much compressed. He has kindly allowed me to
slice two of the specimens, which afford decisive evidence of the former existence of
both an inner and an outer radiating cylinder. The space on the outside of the inner
cylinder does not distinctly show the bundles of vessels communicating with the root-
lets, although there is some evidence of their former occurrence. The bell-shaped
orifices from which the rootlets spring are well displayed, and the space between them
is occupied by wedge-shaped masses of tubes or elongated utricles arranged in radiating
series, and not to be distinguished in any way from those shown in Plate XXXY. fig. 5.
Indeed the transverse section of the specimen there figured would almost do for a
representation of the Stigmaria if the latter had the central axis preserved, which it
unfortunately has not. There is the same internal radiating cylinder, the same space
occupied by lax cellular tissue, which gradually passes into tubes or elongated utricles
arranged in radiating series, apparently diverging from circular openings, and parted by
large bundles of muriform tissue containing vessels barred on all their sides, extending
to the outer bark. The accompanying woodcut (fig. 4) will give a much better idea of
its structure than any laboured description.
Fig. 4.
This specimen clearly proves, by the evidence of internal structure alone, that Stig-
maria is the root of Sigillaria , each of them having an inner radiating cylinder com-
594
ME. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
posed of barred vessels, a space occupied by lax cellular tissue, and an outer radiating
cylinder composed of tubes or elongated utricles.
The broad space intervening between the internal and external radiating cylinders,
filled with lax cellular tissue and traversed by medullary bundles communicating with
the leaves on the outside of the stem, as shown in the specimens described in this paper,
is the only part on which information is required to complete our knowledge of the
structure of the stem of Sigillaria. Fortunately a small specimen of Sigillaria vascu-
laris, kindly presented to me by Mr. Ward, of Longton, a most indefatigable collector,
has enabled me to obtain considerable information on this point. This specimen shows
the rhomboidal scars on the outside of the stem, the two radiating cylinders and the
space between occupied by lax cellular tissue, and traversed by medullary bundles.
The specimen in this woodcut (fig. 5, magnified twice) is of smaller Eig. 5.
size than any previously described by me, but it is, from both its
internal structure and external characters, a small Sigillaria vascu-
laris in its young state, when the two radiating cylinders, especially
the outer one of the plant, were only slightly developed. The
medullary bundles are seen on the outside of the inner radiating
cylinder, and pass, inclining upwards at a small angle, from the inner
cylinder to nearly the outside of the stem. No trace of the outer
cylinder can be seen, so as to enable us to see whether the smaller-
sized medullary bundles coming from the inner cylinder join the
larger ones in the outer cylinder, described in Plate XXXI Y. fig. 2,
and there marked d'. All the tangential sections show the medul-
lary bundles, both in large and small specimens, to be much greater
and stronger in the outer than in the inner radiating cylinder ; but
no evidence has yet been found of the junction of these medullary
bundles to prove that the former run into the latter, or whether the
two are distinct. They consist of hexagonal tubes, barred on all
their sides, surrounded by muriform tissue, that on the outside of the
specimen being of very coarse texture.
Up to this time we possess little information as to the organs of fructification belong-
ing to Sigillaria. In a paper many years since printed by me *, some Stigmarice were
described which were found with their insides full of spores, resembling those which
were found by Dr. Hooker in Lepidodendron. Similar spores are met with in great
abundance in all the seams of splint coal which have been examined by me, the floors
of which, it is well known, are one mass of Stigmarice. In the strata lying around the
large Sigillaria found at Dixon Fold, described by the late Mr. J. E. Bowman^, that
author says, “ they (the trees) lie in a stratum of soft shale about four feet thick, among
which great quantities of nodules containing cones of Lepidostrobus, with pieces of Stig-
marice, &c., were found.”
* Quarterly Journal of the Geological Society, vol. vi. p. 17.
t Transactions of the Manchester Geological Society, vol. i. p. 113.
ME. E. W. BINNEY ON SOME LO WEE-COAL-SEAM FOSSIL PLANTS.
595
Goldenberg gives a description and figures of a cone and spores which he considers
to be the fructification of Sigillaria *. That author, however, does not give any further
evidence of the connexion of the supposed organs of fructification with the stem of
Sigillaria than had been known in England for years, as previously mentioned. The
spores he figures as belonging to Sigillaria are exactly the same as those found by me
in the inside of Stigmaria.
A specimen found in the roof of the same seam of coal in which Nos. 2, 3 & 8 were
met with, but at a different place, was given to me by Mr. W. Butterworth, junior, of
Moorside, near Oldham, and enables me to give evidence, equally strong with that
adduced by Dr. Hooker to prove that Lepidostrobus was the fruit of Lepidodendron , to
show that a Lepidostrobus was the fruit of Sigillaria. Dr. Hooker, in his excellent
paper on this subject f, says, “The doctrine of morphology teaches us that the cone is
nothing more than the leafy apex of a branch whose leaves are modified in form,
generally to the end that they shall perform the office of protecting organs to repro-
ductive bodies ; this is the case of the pine cone, that of the Lycopodium , or Club Moss,
and many other plants.” This specimen is shown in the annexed
woodcut (fig. 6), of its natural size, and exhibits sporangia, like
those described by Dr. Hooker in his memoir previously quoted,
arranged around the axis of the cone, which does not afford the
rhomboidal scars characteristic of the Lepidodendron, but presents
ribs and furrows, with scars, arranged in quincuncial order, like
a small specimen of Sigillaria organum. Certainly, if the axis of
continuation of a branch of Lepidodendron , the axis of this cone
is equally entitled to be classed as the branch of a Sigillaria.
The organs of fructification, which have been called by geolo-
gists fossil cones, and have been classed under the genus Lepido-
strobus, may not only have belonged to Lepidodendron and Sigil-
laria, but it appears nearly certain in my mind that some of them also belonged to Cala-
mites. In a paper published many years since, the apparent connexion of Calamitcs and
Sigillarice was discussed and noticed by the author Since that time he has collected
much further evidence on the structure of Calamites, which he proposes at some future
time to communicate to the Society in a separate memoir.
In all the large specimens of Sigillaria vascularis the outer radiating cylinder has
been considerably disarranged by pressure, the original cylindrical form of the plant
having been changed into that of an elongated oval. This has been more especially the
case with that part of the plant composed of lax and coarse cellular tissue, forming the
* Flora Saraepontana fossilis. Die flora der Yorwelt Saarbriickens, von Fa. Goldenbekg, l]tcs Heft, Tafel x.
figs. 1 & 2.
t Memoirs of the Geological Survey of Great Britain, vol. ii. part 2. p. 452.
+ Philosophical Magazine for November 1847, p. 259.
MDCCCLXV. 5 M
596
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM EOSSIL PLANTS.
inner portion of the outer cylinder, as well as the thick tubes or elongated utricles,
arranged in radiating series, composing the outer part next the bark. Nevertheless in
the former there is nearly always some evidence left of circular openings or eyes sur-
rounded by coarse cellular tissue, which gradually assumes a radiating character, and
from which the wedge-shaped bundles of tubes or elongated utricles proceed and extend
to the outside of the stem. The character of these circular openings, and the wedge-
shaped bundles proceeding from them, is well shown in the young specimen of Sigillaria
vascularis , drawn in Plate XXXI II. fig. 5, and remind us much of what is seen in Cala-
modendron, except that in the latter plant the walls of the tubes exhibit oval openings,
sometimes approaching the form of disks, characters which have not as yet, so far as
my knowledge extends, been observed in the outer cylinder of Sigillaria. In larger and
older specimens, as previously stated, the walls of these tubes or elongated utricles of a
quadrangular form have become much thicker, and cannot be distinguished from those
of Pinites, except by the absence of disks.
The outer cylinder, as before noticed, in large specimens always presents divisional
lines of a rectangular form, filled by spathose matter, in shape very like those now
seen in hard-wooded trees. These appear to me as if made by pressure, but they may
have been formed in the process of drying, before the mineralization of the specimen, as
previously stated ; however, it is still my opinion that these lines originate from pressure
rather than desiccation, as there is little evidence yet published of the subaerial decay
of the vegetable matter now forming coal, while, on the contrary, nearly every seam of
cannel-coal affords abundance of fish remains, and no doubt seams of soft bright coal,
if equally favourable for their preservation, would yield them. My cabinet contains
specimens from the Oldham coal-field of soft bright coal containing undoubted scales
of Rhizodus, given to me by Mr. Wild, of Glodwick, and doubtless many more such
specimens will be found if carefully looked for.
In the outer portion there is always some appearance of concentric rings, no,t unlike
those seen in our present hard- wooded trees, and which my friend Mr. J. S. Dawes,
F.G.S., first noticed in Calamodendron *. This observation of Mr. Dawes many spe-
cimens in my cabinet amply confirm, although they do not bear out that author’s
statement as to Calamodendron having had a pith composed of cellular tissue, as it
undoubtedly possessed a central axis composed of large vessels apparently barred on
all their sides by transverse strise, and not to be distinguished from the same part of
S. vascularis.
Concluding Remarks.
In this memoir the reader will no doubt have seen that it was intended to be more
of a descriptive character than an attempt to trace the analogy of the plants whose
remains have formed our beds of coal with living vegetables. The subject is surrounded
with difficulties, and although the author has been singularly fortunate in meeting with
specimens in a good state of preservation, when compared with most hitherto described,
* Quarterly Journal of the Geological Society, vol. vii. p. 198.
ME. E. W BINNEY ON SOME LOWEE-COAL-SEAM EOSSIL PLANTS.
597
still his information is confined to two plants. These, no doubt, have contributed by their
remains in a great measure to form the two seams of coal in which they were found, as
is evident from the abundance of Sigillaria-roots now found in floors of the beds. In
addition to this fact, the Halifax Hard or Gannister seam yields the Sigillaria vascularis
as by far the most common plant found in it.
The large specimens Nos. 2 & 3, now described and figured, some persons may doubt
as being the older forms of the Sigillaria vascularis described by me some years since in
the Geological Society’s Journal previously quoted, as well as the medium-sized specimen
No. 8 given in Plate XXXV. fig. 5 of this memoir; but the one has been traced
gradually passing into the other so as to leave no doubt on this point, and the internal
structure is unquestionably the same both in the large and small plants, after making
due allowance for the greater age of the former.
The general opinion of botanists and geologists, that Sigillaria was a hollow and
succulent plant, no doubt arose from the flat specimens generally found compressed into
thin plates in indurated clays or shales. The same view was taken with regard to
Calamites , owing to their being nearly always found in a similar condition ; but it is
now well known that many specimens of Calamites are nothing more than the casts of
the central axis of a hard-wooded tree with concentric rings, the whole of which has in
most cases disappeared and left no trace of its former existence. Now, although till
the discovery of my specimens few, if any, large Sigillaria had been found exhibiting
structure, it has been shown that the late Mr. Bowman, an eminent botanist, many
years since pronounced the Dixon Fold fossil trees to be large Sigillarice and hard-
wooded dicotyledonous trees with heavy tops, and this he inferred chiefly from the size
and form of their roots. Long after the last-named author’s death, Dr. Dawson, in
1859, as previously quoted, was inclined “ to suspect that some of the described species
of conifers of the coal may be the woody axes of large Sigillarice , or at least of trees
approaching quite as nearly to those plants as to modern conifers.” Although my
specimens do not altogether support Dr. Dawson's views as to the woody axis he no
doubt refers to, namely, the internal radiating cylinder and not the outward one,
which he terms a very thick cellular inner bark, his opinion is entitled to considerable
weight as to Sigillarice being hard-wooded trees, he having paid great attention to the
different structures found in the charcoal now met with in our coals, the floors of
which so constantly testify to the presence of Sigillaria in the form of roots, and the
great part it contributed to their formation. The size of the external cylinder of this
plant, when compared with its internal one, is so much greater, that by far the larger
portion of the coal must have been derived from the former. It is this part of the fossil
tree that so generally divides into rectangular masses, and not the small internal
cylinder evidently alluded to by Dr. Dawson, as any person who has examined many
large specimens will well know.
Specimen No. 2 probably may not be considered as so marked an example of the
genus Sigillaria , owing to the small size and indistinctness of the cicatrices left by the
5 m 2
598
MR. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
leaves, which are not so well shown in the Plate as they are generally found on speci-
mens of Sigillaria organum. No doubt it cannot be regarded as a good example of the
species organum , but from the ribs, furrows, and scars on its outside no one will question
its being a Sigillaria , even if its internal structure did not prove its relationship to
Sigillaria elegans.
In all my investigations as to the origin of coal, the marine character of the water in
which the plants that formed it by their decomposition grew, becomes to my mind more
evident. It is now well known to all parties conversant with coal-mining, that in most
deep mines where the surface water cannot get down the water found in the coal is
quite salt, and contains iodine, bromine, and the usual constituents of sea-water. Any
person carefully examining each of the seams of coal in which the fossil woods described
in this memoir were found, placed as they are upon an under clay full of Sigillaria- roots
with their radicles traversing it in every direction, will be convinced that the plants
which formed the coal grew on the spot where it is now met with, and were not drifted
there, while the presence of such a mass of marine shells as is found in the roof of each
seam evidently where they lived and died, equally proves the salt nature of the water.
Little evidence is to be obtained of the character of the dry land of the Carboniferous
epoch except what is afforded by a few sun cracks on some of the rocks, but from the
shallow seas more resembling marine swamps than the oceans of the present day, it was
probably little above the surface of the water. Shallow seas and low lands would of
course greatly influence the climate of the period. The strata found in the vicinity of
seams of coal, with some few exceptions, show that they were deposited from water
during periods of great tranquillity, and the vast range over the old and new worlds of
the genus Sigillaria found in all their true coal-fields, indicates a uniformity of condi-
tions of which we have now no parallel, and areas of such immense extent as is only
equalled by some of our present oceans.
In the Lancashire coal-field, probably one of the best developed in Great Britain,
from the bottom to the top there are about 120 different seams of coal, great and small.
These indicate 120 periods of rest or repose of the earth’s crust, when a primeval forest
reared its top above the waters until the vegetable matter now forming each bed of coal
was grown and deposited*. Then such forest was submerged and buried under mud
and sand now found as shale and sandstone rocks. The hollow caused by such subsi-
dence was silted up until it was again covered by shallow water. Then, again, a fresh
crop of vegetation flourished so as to form another bed of coal. For 120 different times
did this successive growth of vegetable matter, submergence and silting up go on. In
some instances whole forests oi Sigillaria, standing upright in fine shale, on the top of the
seams of coal are met with, thus clearly showing that they were submerged quietly and
slowly, whilst at other times the prostrate stems now found lying in sandstone roofs
* Although upright Sigillarice are generally found in the roof of a seam of coal, they are also met with in fine-
grained shales, midway between seams, less frequently in coal floors, and more rarely still in the seams of coal
themselves. — Transactions of the Manchester Literary and Philosophical Society, vol. viii. 2nd series, p. 176.
ME. E. W. BINNEY ON SOME LOWEK-COAL-SEAM FOSSIL PLANTS.
599
show that the submergence was rapid, causing strong currents that tore up and drifted
the trees. Every one of the floors of these coal-seams is full of the roots of Sigillaria ;
so with the stems of these trees in the roof, the vegetable matter in the seam of coal,
and the roots in the floor, there can scarcely be a doubt as to the remains of the vege-
tables now composing coal having grown on the spots where it is now found, and that
Stigmaria was the characteristic root of the plants which for the most part produced
coal.
The above conditions of the growth of vegetables in shallow seas very different to any
state of things now existing, would require a plant suited to them and very different
from any now living. After a careful investigation of the structure of Sigillaria elegans ,
Brongniart came to this conclusion : “ Tous ces motifs doivent nous porter a conclure
que les Sigillaria et les Stigmaria constituaient une famille speciale entierement detruite,
appartenant probablement a la grande division des Dicotyledones gymnospermes, mais
dont nous ne connaissons encore ni les feuilles ni les fruits.”
If we take particular parts of Sigillaria vascularis , as before described, we can trace
resemblances to some living plants. The central axis when taken by itself might appear
to connect the plant with ferns, as it certainly bears some resemblance to the root of
Aspidium exaltatum, as figured by Brongniart in plate 8, figs. 10 & 11*. The internal
radiating cylinder is somewhat like similar cylinders in Echinocactus and Melocactus , as
figured by the same author.
The vessels with barred and dotted sides in some respects resemble those of Zamia
integrifolia , also noticed by Brongniart, and the outer radiating cylinder in the thick-
ness of the walls of its tubes, or elongated utricles, and their arrangement, points to
conifers. Although Sigillaria has resemblance in some of its parts to such widely
different living plants, there can scarcely be a doubt in the mind of any one who has
had the advantage of examining the fossil plant with its far extending roots and long
radicles, but that it had an aquatic habitat. It attained a large size, as upright speci-
mens have been traced by me nearly 60 feet in height without showing much dimi-
nution in size, and the bases of others have come under my observation which have
measured over 7 feet in diameter.
Description of the Plates.
PLATE XXX.
IHploxylm cycadoideum.
Fig. 1. Specimen (No. 1) of one-half of a stem of Diploxylon cycadoideum in a calcified
state, found in the lower coal-measures of Lancashire, in the middle of a seam
of coal, showing a transverse section : natural size.
* Observations sur la structure interieure du Sigillaria elegans, p. 447.
600 MR. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
Fig. 2. A longitudinal section of the same specimen taken across the minor axis from
d to d in fig. 1 : natural size.
Fig. 3. A tangential section of the same specimen taken across the upper part : natural
size.
Note. — The same letters indicate the same parts in this and the preceding
figures, and also in the subsequent ones.
a a. The middle part, showing the central axis or pith composed of large
hexagonal vessels, having all their sides barred by transverse striae.
a ' a'. The smaller hexagonal vessels in the central axis or pith found some-
times interspersed amongst the larger ones, and divided by horizontal septae.
a!’ a!'. Small vessels of very delicate elongated tissue found mixed with the
other vessels in the axis or pith.
b b. The vascular internal cylinder, in wedge-shaped bundles and radiating
series, composed of hexagonal vessels, barred on all their sides by trans-
verse striae, and divided by medullary rays or bundles, b" b".
V V . Portions of the same cylinder disarranged or destroyed.
b" b”. Medullary rays or bundles passing through the internal cylinder, and
extending to the outside of the stem.
c c. Space on the outside of the internal cylinder, composed of lax cellular
tissue, and traversed by vascular bundles frequently disarranged or destroyed
and replaced by mineral matter.
d d. Outer cylinder of tubes or elongated utricles in wedge-shaped bundles,
and radiating series of quadrangular form, divided by wide openings filled
with coarse muriform tissue, which enclose medullary rays or bundles of an
oval or circular form leading to the leaves.
d1 d'. Medullary rays or bundles of barred vessels traversing the coarse muriform
tissue.
d’1 d". Elongated tissue divided by horizontal septae (muriform tissue) sur-
rounding the medullary rays or bundles.
Fig. 4. A transverse section of a portion of the same specimen taken across the minor
axis, showing the whole of the central axis or pith, one side of the inner
radiating cylinder, and the space between the latter and the outside of the
stem : magnified 5 diameters.
Fig. 5. A longitudinal section of the same specimen, showing the same parts of the stem
as are named in the last figure, magnified 5 diameters.
Fig. 6. A tangential section of the same specimen (upper part), magnified 5 diameters,
MR. E. W. BINNEY ON SOME LOWER-COAL-SEAM EOSSIL PLANTS.
601
PLATE XXXI.
Sigillaria vascularis.
Fig. 1 (No. 2). Specimen of a stem of Sigillaria vascularis in a calcified state, found in
the lower coal-measures of the West Hiding of the County of York, at North
Owram near Halifax, in the middle of the Hard bed of coal, showing a front
view of the upper part, containing the central axis, internal vascular cylinder,
space on the outside of the latter composed of coarse cellular tissue, and
external radiating cylinder : natural size.
Fig. 2. Side view of the same specimen, which not only shows the upper part of the
specimen like fig. 1, with the central axis, internal radiating cylinder, inter-
vening space of lax cellular tissue, and external radiating cylinder, but a
side view of the decorticated portion of the stem with irregular ribs and
furrows, on the former of which are traces of the cicatrices left by the leaves
of the plant : natural size.
PLATE XXXII.
Sigillaria vascularis.
Fig. 1 shows a transverse section of the central axis and internal radiating cylinder of
the same specimen, magnified 5 diameters.
Fig. 2. A part of the same specimen, a denoting the central axis, and b the internal
radiating cylinder: magnified 12 diameters.
Fig. 3. A longitudinal section of the same specimen, commencing on the outside of the
internal radiating cylinder passing through the central axis, the other portion
of the internal radiating cylinder, the part composed of coarse cellular tissue
generally disarranged adjoining to it, and the external radiating cylinder to
the outside of the specimen : magnified 4 diameters.
a a. Parts of the central axis composed of hexagonal vessels arranged with-
out order, having all their sides marked by transverse striae.
b b Parts of the internal cylinder, composed of hexagonal vessels in wedge-
shaped bundles, and radiating series marked on all their sides by transverse
striae parted by medullary rays or vascular bundles communicating from the
outside of the central axis to the exterior of the cylinder, and probably
extending on to the leaves.
cc. Parts of the coarse cellular tissue, generally a good deal disarranged,
traversed by large vascular bundles, most probably connected with the medul-
lary rays or vascular bundles of the internal cylinder, and communicating with
the leaves.
602
ME. E. W. BINNEY ON SOME LOWER-COAL-SEAM FOSSIL PLANTS.
d d. Parts of the external cylinder, composed of tubes or elongated utricles
of a quadrangular form arranged in radiating series, and parted by large
vascular bundles surrounded by coarse muriform tissue.
Fig. 4. A tangential section of a portion of the same specimen, magnified 4 diameters.
b. Parts of the internal cylinder, showing a section of the medullary rays or
vascular bundles, b”.
c. Portions of the coarse cellular tissue, generally a good deal disarranged,
traversed by large vascular bundles, most probably connected with the medul-
lary rays or vascular bundles of the internal cylinder, and communicating with
the leaves.
d d. Parts of the external cylinder, composed of tubes or elongated utricles
of a quadrangular form arranged in radiating series, and parted by large vas-
cular bundles surrounded by coarse muriform tissue.
Fig. 4. A tangential section of a portion of the same specimen, magnified 4 diameters.
b b. Parts of the internal cylinder, showing a section of the medullary rays
or vascular bundles, b".
c c. Parts of the coarse cellular tissue somewhat disarranged, but showing
some structure, and traversed by vascular bundles.
d d. Parts of the external radiating cylinder, showing the large oval bundles
of vascular tissue (d1) surrounded by coarse muriform tissue.
PLATE XXXIII.
Sigillaria vascularis.
Fig. 1 shows a longitudinal section of a portion of the same specimen, exhibiting the
central axis composed of barred vessels, a «, parted by smaller vessels divided
by horizontal septse, a!, as well as portions of the internal cylinder composed
of barred vessels, b b : magnified 15 diameters.
Fig. 2 represents two of the barred vessels of the central axis as they would appear if
not ground away in the slicing and polishing, magnified 45 times.
Fig. 3. A tangential section of a portion of the same specimen across a part of the in-
ternal cylinder, showing the medullary rays or bundles (b") traversing the
cylinder b : magnified 15 diameters.
Fig. 4. A longitudinal section of a portion of the external cylinder d, composed of tubes
or elongated utricles arranged in radiating series, magnified 10 diameters.
Fig. 5. A tangential section of a portion of the external cylinder, showing the large
vascular bundles of an oval shape, d ', surrounded by coarse muriform tissue
which traverse it : magnified 10 diameters.
ME. E. W. BINNEY ON SOME LOWEK-COAL-SEAM FOSSIL PLANTS.
603
PLATE XXXIV.
Sigillaria vascularis.
Fig. 1. Specimen (No. 3) of a stem of Sigillaria vascularis in a calcified state, found also
in the lower coal-measures of North Owram in the middle of the Hard bed of
coal, in company with the last specimen described, showing a portion of the
central axis divided and partly disarranged, portions of the internal cylinder
composed of hexagonal vessels having all them sides marked with transverse
striae, arranged in radiating series parted by medullary rays or vascular bundles ;
also a part of the space on the outside of the internal cylinder, composed of
coarse cellular tissue, and parts of the external cylinder, composed of tubes or
elongated utricles arranged in radiating series, and parted by large vascular
bundles surrounded by coarse muriform tissue communicating with the leaves.
The outside of the specimen presented the same kind of ribs and furrows,
with indistinct traces of cicatrices, as the specimen No. 2, described in Plates
XXXI., XXXII., and XXXIII. It is given chiefly for the purpose of
showing the tubes or elongated utricles of the external cylinder, traversed
by the large vascular bundles of an oval form, surrounded by coarse muriform
tissue which are much more distinctly represented than in the first-named spe-
cimen No. 2 : magnified 2 diameters.
Fig. 2. A tangential section of the same specimen, showing a portion of the outer cylinder,
composed of tubes or elongated utricles, d d, traversed by large vascular bundles
of the shape of a double cone, composed of very large horizontally-divided
tissue, d1, and more finely divided tissue, d" d", and having an oval-shaped vas-
cular bundle in the middle, most probably communicating with the cicatrices
to which the leaves were attached on the outside of the plant : magnified 20
diameters.
Fig. 3. A longitudinal section of the same specimen, showing a portion of the outer
cylinder, composed of tubes or elongated utricles, d, arranged in radiating series,
as well as a portion of a vascular bundle with the fine tissue divided by hori-
zontal partitions, d" : magnified 20 diameters.
PLATE XXXV.
Sigillaria vascularis.
Figs. 1, 2, & 3 (Nos. 4, 5, & 6) represent the external appearance of the central axes of
three different specimens of Sigillaria vascularis , found in the middle of the
Hard seam of coal in company with the specimens Nos. 2 & 3 described in
Plates XXXI., XXXII., XXXIII., and XXXIV. They were enclosed in
three stems, exactly resembling those specimens in external characters and
mdccclxv. 5 N
604
ME. E. W. BINNEY ON SOME LOWEE-COAL-SEAM FOSSIL PLANTS.
internal structure in every respect. The horizontal division, in fig. 1 may pro-
bably owe its origin to a fissure in the stone rather than a division such as
is usually seen in a Calamites, hut the outside longitudinal striae in all the spe-
cimens remind us of that fossil plant, while the vascular bundles of the central
axis of these specimens' bear considerable resemblance to some of the species
of Medullosa: magnified 2\ diameters
Fig. 4 (No. 7) represents the outside of the inner radiating cylinder of Stigmaria
ficoi&es arranged in wedge-shaped bundles, showing the finely marked longi-
tudinal striae with which it was furnished, but not affording any evidence of
structure in the central axis : magnified 2\ diameters. This specimen is from
the Wigan Five Feet seam of coal of the Ince Hall Coal and Cannel Company,
in the middle division of the Lancashire coal-measures, and is the only speci-
men which has come under my notice which shows the outside of the inner
radiating cylinder : magnified 24 diameters.
Fig. 5 (No. 8) represents a transverse section of a small specimen oi Sigillaria vascu-
laris, found also in the lower coal-measures of North Owram, in the middle of
the Hard bed of coal. It is in a more perfect condition, as a whole, than any
of the other specimens described in this paper, and appears to be a younger
individual of the same genus and species as the larger and more imperfect
ones, Nos. 2 & 3, figured in Plates XXXI., XXXII., XXXIII., and XXXIV.,
associated with which it was found. It shows the central axis, composed of
hexagonal vessels arranged without order, and having all their sides marked
with horizontal striae, the internal cylinder of hexagonal vessels arranged in
radiating series, and having all their sides marked with transverse striae and
parted by medullary rays or vascular bundles, the space outside that cylinder
occupied by lax cellular tissue traversed by vascular bundles, sections of some
of which are seen as circular openings, a dark line bounding it, the zone of
coarse cellular tissue outside that last named containing circular and oval
openings, and passing into tubes or elongated utricles arranged in radiating
series, and divided by large medullary rays or vascular bundles, forming the ex-
ternal cylinder, and an outer bark enveloping the plant : magnified 4 diameters.
Fig. 6 (No. 8) represents the outside view of the same specimen partly covered by a
thick carbonaceous coating, probably representing the outer bark and partly
decorticated, displaying rhomboidal scars, having a rib running through their
major axis, in the middle of which is a cicatrix of a circular form left by the
leaf. The scars and cicatrices upon them were arranged in quincuncial order.
The specimen appears to be older than those described by me in the Geo-
logical Journal previously alluded to, and younger than specimens 2 & 3 of
this paper : magnified 2\ diameters.
Phil. Tran^. MDCCCLXV. Pb.IXX.
Plai&A.l.
3.
J. N.Titdh.,deL.eb lith.
Vincent Brooks, Imp
Phil. Trans. MI) CCCLXV. PI. XXXI.
PlaUA.il.
J. N .Fitch., del. et Isth.
Phzl. Trans. MD CCCLXV: PIXXXIL
|^T:Tiwb,ariL.et Ji£h
PM. Trans. MDCCCLXV. PI. I.
Plate. A. V.
J. N. Fitch, del.eb lith
"Vincent Bro oks , Imp .
Phil . Trans. MB CCCLXV. Film
J . N Hitch, del.et jith .
[ 605 ]
XII. The Bakerian Lecture. — On a Method of Meteorological Registration of the
Chemical Action of Total Daylight*. By Henry Enfield Roscoe, B.A., F.B.S. ,
Professor of Chemistry in Owens College , Manchester.
Received November 8, — Read December 22, 1864.
In the last memoir on Photochemical Measurements, presented to the Royal Society f,
Professor Bunsen and I described a method for determining, by simple observations, the
varying amount of chemical action effected by the direct and diffuse sunlight on photo-
graphic paper, founded upon a law discovered by us, viz. that equal products of the
intensity of the light into the times of insolation correspond within very wide limits to
equal shades of tints produced on chloride-of-silver paper of uniform sensitiveness — so
that light of the intensity 50, acting for the time 1, produces the same blackening effect
as light of the intensity 1 acting for the time 50. For the purpose of exposing this paper
to light for a known but very short length of time, a pendulum photometer was con-
structed ; and by means of this instrument a strip of paper is so exposed that the different
times of insolation for all points along the length of the strip can be calculated to within
small fractions of a second, when the duration and amplitude of vibration of the pen-
dulum are known. The strip of sensitive paper insolated during the oscillation of the
pendulum exhibits throughout its length a regularly diminishing shade from dark to
white ; and by reference to a Table, the time needed to produce any one of these shades
can be ascertained. The unit of photo-chemical intensity is assumed to be that of the
light which produces upon the standard paper in the unit of time (one second) a given but
arbitrary degree of shade termed the normal tint. The reciprocals of the times during
which the points on the strip have to be exposed in order to attain the normal tint, give
the intensities of the acting light expressed in terms of the above unit.
According to this method the chemical action of the total daylight (*. e. the direct
sunlight and the reflected light from the whole heavens) has been determined, by means
of observations made at frequent intervals throughout the day, and curves representing
the variation of daily chemical intensity at Manchester have been drawn The labour
of obtaining a regular series of such daily measurements of the chemical action of day-
light according to this method is, however, very considerable ; the apparatus required
* It is to be carefully borne in mind that no absolute measurement of the more refrangible solar rays falling
on the earth’s surface is possible, except by the expression of their heat-producing effect ; and that all methods
of measuring the intensity of these rays depending upon the action which they produce on any single chemical
compound, give results which are only true for the particular rays affecting the compound selected as the standard
of comparison.
t Philosophical Transactions, 1863, p. 139. + Ibid. 1863, p. 160.
MDCCCLXV. 4 0
606
PROFESSOR ROSCOE ON A METHOD OF METEOROLOGICAL
is bulky, the observations can only be made in calm weather, and the quantity of sensi-
tive paper needed for a day’s observations is large.
The aim of the following communication is to describe a very simple mode of deter-
mining at any moment the chemical action of the whole direct and diffuse sunlight (as
measured by chloride-of-silver paper) adapted to the purpose of regular meteorological
registration, and founded upon the principles laid down in the memoir above alluded to.
According to this method a regular series of daily observations can without difficulty be
kept up at frequent intervals. The whole apparatus needed for exposure can be packed
into very small space ; the observations can be carried on without regard to wind or
weather; and no less than forty-five separate determinations can be made upon
36 square centimetres of sensitive paper.
Strips of the standard chloride-of-silver paper tinted in the pendulum photometer
remain as the basis of the more simple mode of measurement now to be described.
Two strips of this paper are exposed as usual in the pendulum photometer ; one of these
strips is fixed in hyposulphite-of-sodium solution, washed, dried, and pasted upon a
board furnished with a millimetre-scale. This fixed strip is now graduated in terms of
the unfixed pendulum strip by reading off, with the light of a soda-flame, the position
of those points on each strip which possess equal degrees of tint, the position of the
normal tint upon the unfixed strip being ascertained for the purpose of the graduation.
The fixed strip thus becomes in every respect equivalent to the unfixed strip. Upon
this comparison with the unfixed pendulum strip depends the subsequent use of the
fixed strip. In order to understand how the chemical action of daylight can be
measured by help of this fixed and graduated strip, let us suppose, in the first place, that
we have ascertained the position of those points upon the fixed strip which possess an
equal degree of tint to points on the unfixed strip situated at regular intervals, say
10 millims. from each other. By reference to Table I. of the above-mentioned memoir,
given below, we then find the relation between the times of exposure necessary to effect
the tints in question when the intensity of the light remains constant.
Let us suppose, in the second place, that the position on the unfixed strip of
which the shade corresponds to that of the normal tint has been found ; and that
the time of exposure, placed opposite to this position in Table I., has been noticed.
If, now, the various tints on the strip had been produced in one and the same time by
lights of different intensities, instead of being effected by light of the same intensity
acting for different times, the law above alluded to shows that the numbers found in
the Table would represent the relation of these different intensities ; so that in order
to express this relation in terms of the unit of intensity employed, it is only necessary
to multiply the numbers thus obtained by a constant, viz. the reciprocal of the number
found in column II. of the Table, opposite to the position in column I., giving the point
on the unfixed strip equal in shade to the normal tint. An example may serve to
make this calculation plain : (1) The position on the unfixed strip equal in shade to the
normal tint was found to be 112 millims. ; (2) the positions on the fixed strip equal in
REGISTBATION OF THE CHEMICAL ACTION OF TOTAL DAYLIGHT.
607
Table I.
I.
Millims.
II.
Seconds.
I.
Millims.
II.
Seconds.
I.
Millims.
n. 1
Seconds.
I.
Millims.
II.
Seconds.
I.
Millims.
II.
Seconds.
I.
Millims.
II.
Seconds.
0
1-200
32
1-003
64
0-846
96
0-700
128
0-549
160
0-369
1
M93
33
0-998
65
0-841
97
0-695
129
0-544
161
0-363
0
1-186
34
0-993
66
0-837
98
0-691
130
0-539
162
0-357
3
1-179
35
0-988
67
0-832
99
0-686
131
0-534
163
0-350
4
1*1 72
36
0-983
68
0-828
100
0-682
132
0-528
164
0-343
5
1-165
37
0-977
69
0-823
101
0-677
133
0-523
165
0-336
6
1-158
38
0-972
70
0-819
102
0-672
134
0-518
166
0-329
7
1-151
39
0-967
71
0-814
103
0*668
135
0-513
167
0-321
8
1-144
40
0-962
72
0-809
104
0-663
136
0-508
168
0-314
9
1-137
41
0-957
73
0-805
105
0-659
137
0*502
169
0-309
10
1-131
42
0-952
74
0-800
106
0-654
138
0-497
170
0-300
11
1-125
43
0-947
75
0-796
107
0-650
139
0-492
171
0-291
12
1-119
44
0-942
76
0-791
108
0-645
140
0-487
172
0-283
13
1-113
45
0-937
77
0-786
109
0-640
141
0-482
173
0-274
14
1-106
46
0-932
78
0-782
110
0-635
142
0-476
174
0-266
15
1-100
47
0-927
79
0-777
111
0*631
143
0-470
175
0-257
16
1-094
48
0-922
80
0-773
112
0-626
144
0-465
176
0-249
17
1-087
49
0-917
81
0-768
113
0-621
145
0-459
177
0-240
18
1-081
50
0-912
82
0-764
114
0-617
146
0-453
178
0-229
19
1-076
51
0-907
83
0-759
| 115
0-612
147
0-448
179
0-219
20
1-070 1
52
0-903
84
0-755
116
0-607
148
0-442
180
0-208 !
21
1-064
53
0-898
85
0*750
117
0-603
149
0-436
181
0-198 j
22
1-058
54
0-893
86
0-745
118
0-598
150
0-431
182
0-187
23
1-053
55
0-888
87
0-741
119
0-593
151
0-425
183
0-176 I
24
1-047 j
56 .
0-884
88
0-736
120
0-588
152
0-419
184
0-161
25
1-041
57
0-879
89
0-732
121
0-583
153
0-413
185
0-146
26
1-036
58
0-874
90
0-727
122
0-578
154
0-407
186
0-131
27
1-030
59
0-870
91
0-723
123
0-573
155
0-401
187
0-116
28
1-025 I
60
0-865
92
0-718
124
0-568
156
0-394
29
1-019
61
0-860
93
0-714
125
0-563
157
0-388
30
1-014
62
0-856
94
0-709
126
0-558
158
0-382
31
1-009
63
0-851
1
95
0-704
1 127
0-553
159
0-376
tint to two points on the unfixed strip situated 10 millims. on each side of this, were
found to be 100 millims. and 123 millims; (3) by reference to the Table, the relation
between the intensities on these two positions is found to be as 0672 to 0578;
(4) these numbers, multiplied by qt the reciprocal of the intensity corresponding to
112 millims., give the intensities expressed in terms of the unit formerly employed,
which acting for one second produce the tints in question.
The method of observation thus becomes very simple. To each of the fixed and
graduated strips an Intensity Table is attached, giving the value of the tints upon each
millimetre of its length in terms of the described unit ; a piece of standard sensitive
paper is exposed for a known number of seconds to the light which it is required to
measure, until a tint is attained equal to some one of the tints upon the strip ; the
exact position upon the strip of equality of tint to the exposed paper is next read off by
the light of the soda-flame ; the number found in the Intensity Table opposite to this
position, divided by the time of exposure in seconds, gives the intensity of the acting
light in terms of the required unit.
A detailed description of the apparatus employed, and of the methods of preparing
and graduating the strips, will be given under separate headings.
4 o 2
608
PROFESSOR ROSCOE ON A METHOD OF METEOROLOGICAL
The following conditions must be fulfilled in order that this method can be adopted
as a reliable measurement of the chemical action of light : —
1st. The tint of the standard strips fixed in hyposulphite must remain perfectly
unalterable during a considerable length of time.
2nd. The tints upon these fixed strips must shade regularly into each other, so as to
render possible an accurate comparison with, and graduation in terms of, the
unfixed pendulum strips.
3rd. Simultaneous measurements made with different strips thus graduated must
show close agreement amongst themselves, and they must give the same results
as determinations made by means of the pendulum photometer, according to
the method described on pages 158, 159 of the last memoir.
I. Preparation of the Standard fixed Strips.
For the purpose of preparing the fixed strips, sheets of good white photographic
paper are salted in a solution containing 3 per cent, of chloride of sodium, exactly
according to the directions given in the last memoir (p. 155) for the preparation of the
standard paper. The salted paper after drying is cut into pieces, 16 centimetres in
length by 15 centimetres in breadth, and silvered on a bath containing 12 parts of
nitrate of silver to 100 parts of water. After drying, one of these papers is fixed at the
corners upon a board covered by a well-fitting lid of sheet zinc, so made that it does not
touch the paper ; the paper is then blackened by exposure to the action of light in the
pendulum apparatus. For this purpose, the thin elastic sheet of the blackened mica
usually employed, is replaced by a piece of thin sheet zinc 16 centimetres broad. The
frame carrying the paper is clamped on to the horizontal plate of pendulum photo-
meter, and the sheet of blackened zinc placed over it ; the cover is then withdrawn,
and the paper exposed by allowing the pendulum, with the sheet of zinc attached to it,
to vibrate until the required tint has been attained. The cover is then replaced, the
frame opened in the dark room, the paper washed to remove excess of nitrate of silver,
fixed in a saturated solution of hyposulphite of sodium, and well washed for three days.
As the tints of the foxy-red colour which the paper possesses after fixing can be accu-
rately compared with the bluish-grey tint of the freshly-exposed paper by means of the
monochromatic light of the soda-flame, the use of a toning-bath was specially avoided
as likely to render the paper liable to fade. Each sheet thus prepared is cut into four
strips, 160millims. long and 30 millims. broad, which are then preserved for graduation.
In order to ascertain whether these fixed strips undergo any alteration in tint by
exposure to light, or when preserved in the dark, two consecutive strips were cut off
from several different sheets, and the point on each at which the shade was equal to that
of the standard tint (see last memoir, p. 157) was determined by reading off with the
light of the soda-flame, by means of the arrangements fully described on p. 143 of the
above-cited memoir. One-half of these strips were carefully preserved in the dark, the
other half exposed to direct and diffuse sunlight for periods varying from fourteen days
to six months, and the position of equality of tint with the standard tint from time to
REGISTRATION OE THE CHEMICAL ACTION OF TOTAL DAYLIGHT.
609
time determined. It appears, from a large number of such comparisons, a few of which
only are given below, that in almost all cases an irregular, and in some instances a rapid
fading takes place immediately after the strips have been prepared, and that this fading
continues for about six to eight weeks from the date of the preparation. It is, however,
seen that, after this length of time has elapsed, neither exposure to sunlight nor preser-
vation in the dark produces the slightest change of tint, and that, for many months
from this time forward, the tint of the strips may be considered as perfectly unalterable.
(1) Experiments showing the alteration of tint ensuing immediately after preparation.
Each number given below represents the intensity (see Table II., p. 159 of the last
memoir) corresponding to the mean of ten independent readings on each strip upon the
under-mentioned days.
Sheet No. 1, prepared December 9, 1863,
Intensity.
1st Reading,
Dec. 16, 1863.
Intensity.
2nd Reading,
Jan. 7, 1864.
Diminution in
three weeks.
Strip A, exposed to sunlight...
2*49
2-05
0*44
Strip B, preserved in the dark
2-49
2*01
0-48
Sheet No. 2, prepared December 9, 1863.
Strip A, exposed to sunlight...
2-21
1-86
0-35
Strip B, kept in the dark
2-21
2-03
0-18
From these numbers it is seen that the fading which occurs immediately after pre-
paration is not dependent upon exposure, a change of the same kind being observed in
those strips which were protected from the action of light.
(2) Experiments showing the permanency of tint after lapse of some time from date of
preparation.
Sheet No.
3, prepared September 21, 1863.
Intensity.
Intensity.
Intensity.
Intensity.
1st Reading,
2nd Reading,
3rd Reading,
4th Reading,
Dec. 10, 1863.
Dec. 18, 1863.
Jan. 11, 1864.
Feb. 4, 1864.
Strip A, exposed to sunlight...
1*40
1-40
1-38
1-36
Strip B, kept in the dark
1-38
1-37
1*39
1-35
Sheet No. 4, prepared September 21, 1863.
Strip A, exposed to sunlight...
1*45
D39
1-39
1-38
Strip B, kept in the dark
1-43
1-43 |
1-45
1-46
610
PROFESSOR ROSCOE ON A METHOD OF METEOROLOGICAL
(3) Experiments showing alteration and subsequent permanency of Tint.
Sheet No. 5, prepared March 10, 1864.
Intensity.
Intensity.
Intensity.
Intensity.
Intensity.
Intensity.
1st Reading,
2nd Reading,
3rd Reading,
4th Reading,
5th Reading,
6th Reading,
Mar. 12, 1864.
Mar. 21, 1864.
Apr. 27, 1864.
May 11, 1864.
June 3, 1864.
July 18, 1864.
Strip A, exposed to sunlight...
2-08
213
1*93
1-99
2-03
1*89
Strip B, in the dark
2-10
2-13
1*93
1-93
1*89
1-89
Sheet No. 6,
prepared March 10, 1864.
Strip A, exposed to sunlight...
2-23
2*23
2-13
2-15
2-15
2-10
Strip B, kept in the dark
2-23
2*23
1-99
2-01
2-08
1-97
Sheet No. 7, prepared March 10
CO
3
Strip A, exposed to sunlight...
2-35
2-42
2-08
2-18
2-13
2-01
Strip B, kept in the dark
2-35
2*54
2-01
2-03
2-08
2-03
The above numbers show that, after the standard fixed strips have been prepared for
about two months, the tints remain constant both when the paper is exposed to light
and when it is kept in the dark. The small differences seen in some instances arise
from unavoidable experimental errors of various kinds.
II. Graduation of the fixed Strips in terms of the Standard Pendulum Strips.
The value of the proposed method of measurement entirely depends upon the possi-
bility of accurately determining the intensities of the various shades of the fixed strips
in terms of the known intensities of the standard strips prepared in the pendulum pho-
tometer.
Two modes of effecting this graduation, and of comparing the accuracy of the gra-
duation of one strip with that of another, were employed.
The first of these methods consists in determining by direct comparison the points on
the fixed strip having equal intensities to points on the pendulum strip. For this
purpose the position of the standard tint upon the pendulum strip was first observed ;
circular pieces of this strip, situated 20 millims. apart, were then stamped out with a
punch 5 millims. in diameter, and half of each circle pasted on to the wooden reading
block (fig. 4 of the last memoir), so that the centre of the paper circle came into the
centre of the hole. The readings were conducted in the way described on p. 159 of the
last memoir, every comparison being made independently ten times by each of two
observers, and the mean reading taken as the result, whilst several pendulum strips were
used for the graduation of one fixed strip. The following may serve as an example of
the first method of graduation. Four pendulum strips were employed for the graduation
of the fixed strip A.
KEGISTKATION OF THE CHEMICAL ACTION OF TOTAL DAYLIGHT. 611
Graduation of fixed strip A.
Position of standard tint upon pendulum strip No. 1 = 85 millims., from which the
constant zr~ -z is found in Table I. p. 607.
0*750 A
The position 20 mm. on pendulum strip =1*427 intensity, and corresponds to 67*4 mm. on fixed strip.
40
, 1-283
„ 79-8
„
60
, 1-154
„ 83-0
„
80 „
1-031
„ 91-6
„
100
0-910
„ 94-5
„
120
0-784
„ 119-8
„
140
0-650
„ 121-6
„
In like manner the constants for three other pendulum strips were determined.
Constant for pendulum strip No. 2=0.^--
Constant for pendulum strip No. 3=^^-*
Constant for pendulum strip No. 4=Q.^Q--
By comparison of each of these three pendulum strips with the fixed strip the follow-
ing numbers were obtained. Column I. gives the readings on the millimetre-scale of
the fixed strip ; Column II. the corresponding intensities calculated as in the foregoing
example.
Wo. 2.
No. 3.
No. 4.
I.
II.
I.
II.
I.
II.
26-0
2-12
49-9
1-76
34-6
2-10
35-3
1-90
60 0
1-59
40-4
1-89
55-5
1-69'
70-5
1-43
53-4
1-70
72-6
1-47
81-5
1-27
64-8
1-52
80-1
1-25
92-4
M2
82-5
1-16
90-5
1 00
103-0
0-97
93-0
0-96
121-4
0-80
123-6
0-72
131-5
0-61
In order to obtain the mean result of these numbers, the curve for each of the four
graduations was drawn, the abscissae giving the positions on the fixed strip in millimetres,
and the ordinates the intensities corresponding to these positions. A curve was then
interpolated, lying as nearly as possible between the points determining the single obser-
vations, and from this mean curve the intensity for each millimetre on the scale was
calculated. The following are these tabular values for every 10 millims. Column I.
gives the position in millims. on the fixed strip, Column II. the corresponding intensity,
and Column III. the mean tabular error.
612
PROFESSOR ROSCOE ON A METHOD OF METEOROLOGICAL
I.
II.
III.
I.
II.
HI.
20
2-30
0-10
70
1-47
0-022
30
2*10
0*09
80
1-28
0-010
40
1-90
0-02
90
1-07
0-045
50
1*76
0-016
100
0-916
0-053
60
1-62
0-013
110
0-830
0-056
120
0-755
0-050
A comparison of the several curves of the graduation of strip A found in Plate XXVIII.
fig. 1 shows that the determinations agree as well as can be expected from such photo-
metric experiments ; the mean tabular error between the positions 40 and 80 millims.
on the strip not exceeding one per cent, of the measured intensity.
For the second method of graduation sheets of paper tinted by lithography of a
brownish colour and of different shades are employed, and a portion of each sheet is cut
out, so that the several tints differ considerably from each other, and correspond to the
tints taken at definite intervals along the fixed strip. These are then gummed over half
the reading block, and the value of each read off on several pendulum strips, the inten-
sity of which had previously been determined by the normal tint. Having thus obtained
the intensity of each of the fixed tints, the fixed strip is graduated in terms of the pen-
dulum strip by determining the points on the former equal in intensity to the fixed tints.
This method possesses several advantages over that just described, and is to be preferred
to it, although the comparison is an indirect one, as the intensity of the fixed tints can
be found with a great degree of accuracy by repeated measurements ; and when their
intensities a.re once determined they can be preserved for a length of time, as they do
not undergo any change of shade, and therefore can serve for the graduation of a large
number of fixed strips ; the preparation of which is accordingly not dependent, as is the
case in the first method, upon the state of the weather.
The following numbers may serve as an example of this method :
(1) Determination of the intensity of fixed tints upon pendulum strips.
No. 1.
No. 2.
No. 3.
No. 4.
No. 5.
No. 6.
No. 7.
No. 8.
No. 9.
No. 10. j
No. 11.
No. 12.
Reading of normal tint on pendulum 1
strip J
Reading on pendulum strip of fixed 1
tint No. I. J
„ No. II.
„ No. III.
„ No. IV.
„ No. V.
153-2
mm.
82-0
mm.
131-1
mm.
136-6
mm.
1057
mm.
17-5
mm.
121-6
19-2
mm.
51-9
mm.
131-6
mm.
119-4
mm.
98-0
40-3
90-4
115-7
297
1087
50
50-2
91 0
159-5
67-2
1007
25-4
661
50-5
125-8
990
s’i-2
120-6
93-0
1500
157
50-1
24-5
52-3
89-3
145-5
22-6
517
134-0
The intensities for each determination of a fixed tint are obtained from the above
numbers by dividing the numbers found in Column II. of Table I. (p. 607) opposite the
millimetre readings of each fixed tint by those found in the same Table opposite to the
readings of the normal tint.
REGISTRATION OF THE CHEMICAL ACTION OF TOTAL DAYLIGHT.
G13
Intensity of Fixed Tints.
Fixed Tint.
Expt. 1.
Expt. 2.
Expt. 3.
Expt. 4.
Expt. 5.
Expt. 6.
Expt. 7.
Expt. 8.
Expt. 9.
Expt. 10.!
Expt. 11.
Expt. 12.
I.
2-336
2185
2067
1-768
n.
1-767
1-709
1-647
1-585
1-689
1-524
1-548
hi.
1-480
1-328
1-356
1-346
1-276
1-182
1-289
1-235
1-317
IV.
V.
0-840
0-698
0-891
0-515
0-838
0-544
0-794
0-473
0-773
0-755
Mean Intensity.
Fixed Tint No. 1 2-089 Fixed Tint No. IV 0-798
„ II 1-637 „ V 0-512
„ III 1-312
(2) Graduation of fixed strips B and C, by means of the fixed tints. The graduation of
the fixed strips by means of the fixed tints is now made in the way described in the
first method.
Headings on
fixed strip B.
Headings on
fixed strip C.
Corresponding
intensity.
millims.
millims.
millims.
Fixed tint I.
20-2
27*7
2-089
„ II
3-88
42-8
1-637
„ III
67-3
71-7
1-312
„ IV
105-1
100-6
0-798
„ V
129-0
122-6
0-512
Standard tint
96-0
97-5
1-000
The Intensity Tables for these two strips are obtained by careful graphical interpola-
tion from the above numbers ; the curves are given (in black) on Plate XXVIII. fig. 2,
the abscissae representing the position on the millimetre-scale of the strips, and the
ordinates the corresponding intensities. In every case the normal tint (intensity =1-00)
is read off on the fixed strip, serving as a control of the accuracy of the graduation.
A second series of intensity determinations of the same fixed tints with pendulum
strips is appended for the purpose of controlling the accuracy of the first series. The
intensities of the fixed tints thus obtained are given in the 3rd column of the following
Table. A new fixed tint, No. III. A, was introduced of a shade between Nos. III. and
IV. This new tint was found to coincide with the positions 82-1 millims. and 82-3
millims. on the strips B and C respectively. The readings of the remaining tints are the
same as in the first series.
(3) Second graduation of Strips B and C.
I.
II.
m.
Headings on
strip B.
Headings on
strip C.
Corresponding
intensity.
Fixed tint I
20-2
27-7
1-935
„ II
38-8
42-8
1-597
„ III
67-3
71-7
1-291
„ III A....
82-1
82-3
1-123
„ IV
105-1
100-6
0-807
„ V
129-0
122-6
0-547
Standard tint
96-0
97-5
1-000
4 p
MDCCCLXV.
614
PROFESSOR ROSCOE ON A METHOD OF METEOROLOGICAL
The Intensity Tables for strips B and C obtained by graphical interpolation from both
the above determinations, are those used in most of the observations of daily chemical
intensity about to be described. The curves of these two last graduations are given
(dotted lines) on Plate XXVIII. fig. 2 ; and from these curves the close agreement of
the graduations is seen.
The fixed strip graduated according to the above method is gummed upon the brass
drum (M) of the reading-apparatus, fig. 6, care being taken to place a thick sheet of
white paper between the metal and the fixed strip. In this position it is ready for use.
III. Method of Exposure and Heading.
For the purpose of making the observations, standard sensitive paper is prepared,
according to the directions given on p. 155 of the last memoir, by salting photographic
paper in a 3 per cent, solution of chloride of sodium, and subsequently silvering on a
bath containing 12 parts of nitrate of silver to 100 of water. After drying in the dark,
the paper is cut into pieces 100 millims. long by 10 millims. wide, and each piece gummed
upon the back of an insolation-band (fig. 4) in the position denoted by the dotted lines, so
Fig. 4.
that the lower half of each of the nine holes (5 millims. in diameter) stamped out of the
paper 10 millims. apart, is filled up with the sensitive preparation. These insolation-
bands may be easily cut out of white cartridge paper by means of an iron ruler 400
millims. long and 35 millims. broad, the holes in the paper being stamped out by a
punch fitting into nine corresponding holes in the ruler. The holes in the paper are
numbered, and the numbers are repeated upon the band at a distance of 87 millims.
from each hole for the purpose of subsequent adjustment.
The insolation-apparatus (fig. 3) consists of a thin metal slide (A) 174 millims. in length
and 40 millims. wide, with space enough between the sides to allow the paper band (B) to
pass through easily. A circular opening (C) 10 millims. in diameter is cut in the middle
of the upper side of the slide, and the marks on the bands are so arranged that the line
marked No. 1 coincides with one end of the slide when the centre of the hole No. 1 in
the band coincides with the centre of the opening (C) in the slide. A thin slip of brass
(E) moves easily over the slide, and when brought into the position shown by the dotted
lines, effectually protects the sensitive paper from the action of the light. If the slide
(A) be used alone, the cover (E) can be moved by means of a button placed at the back
of the slide ; it is, however, more convenient to place the slide upon the stand (G), to
which a lever handle (F) is attached, fitting into the button for the purpose of enabling
the observer to cover and uncover the opening with greater ease and exactitude than is
practicable when the hand alone is used. When the intensity of the light is such that
REGISTRATION OF THE CHEMICAL ACTION OF TOTAL DAYLIGHT. 615
the time of insolation does not exceed 2 or 3 seconds, the error introduced by this
opening and closing may become considerable ; for the purpose of diminishing this error
by increasing the duration of exposure, the intensity of the acting light is decreased by
a known amount by allowing the circular disk of blackened metal (fig. 5), out of which
two segments, each of -^-th of the whole area, have been cut, to revolve rapidly close
above the upper surface of the slide (A) ; the spindle of the disk, for this purpose, fitting
into the socket (S, fig. 3) on the stand. As the rate of rotation of the disk does not
affect the accuracy of the result, it is made to revolve by turning the spindle with the
hand. In order that the insolation-band carrying the sensitive paper may be made to
press close against the lower edge of the opening (C), a piece of cartridge paper is placed
underneath it, having several thicknesses of paper pasted at the part underlying the
opening, whilst the ends of the same are made fast at the back of the slide. To enable
the operator to observe when the paper has been sufficiently exposed, a small piece of
photographically-tinted fixed paper of the requisite degree of shade is gummed upon
the surface of the permanent paper band so as to lie directly under the opening (C).
When one observation has been made and the time and duration of the insolation
noted, the remaining papers can be similarly exposed at any required time, by successively
bringing them under the central opening (C), the right adjustment being ensured by
making the corresponding mark coincide with the end of the slide. When all the nine
papers upon the band have thus been exposed, it can be withdrawn and a second band
prepared, as the first can be substituted without the necessity of bringing the apparatus
into a dark room. This is done by means of a small black silk bag or sleeve, open at
both ends ; one end can be closed round the end of the brass slide by an elastic band,
and the other is left open to admit the hand. When it is required to withdraw an inso-
lation-band from the slide, the end of the paper is drawn out into the bag and the band
rolled up into a small coil, and thus preserved until it can be read off, whilst the new
4 p 2
616
PEOFESSOE EOSCOE ON A METHOD OF METEOEOLOGICAL
band is introduced into the bag in the form of a coil, then unwound and pushed into
the slide.
The reading-instrument is represented by fig. 6. It consists essentially of a metallic drum
80 millims. in diameter and 37 millims. broad, upon which a piece of thick white cartridge
paper, and over it the graduated strip, is fastened. The edge of the drum is furnished
with a millimetre-scale, and the dark end of the strip is made to coincide with the com-
mencement of the scale. The drum turns upon a horizontal fixed axis against a vertical
circular plate (N), being held in position by the screw (O). The drum and vertical plate
are fixed upon a pillar and foot (P). The insolation-band is held against the graduated
strip by means of two spring clamps (QQ'), placed apart at a distance of 130 millims. and
fixed to the vertical plate (N). By moving the drum on its horizontal axis, the various
shades of the fixed strip can be made to pass and repass each of the holes on the insola-
tion-band, and the points of coincidence in tint on the strip and each of the insolated
papers can be easily ascertained by reading off by the light of a soda-flame in a dark
room. The lens (B.) fixed upon the brass pillar of the instrument serves to concentrate
the light from the flame upon the small surface under examination. If a coal-gas flame
can be procured at the Observatory, the best mode of obtaining the monochromatic light
is to place two beads of sodic carbonate upon fine platinum loops into the colourless
flame of a Bunsen burner ; if a coal-gas flame cannot be obtained, the flame of a lamp
fed with spirit saturated with common salt can be used, and beads of the more volatile
sodic chloride held into the flame. The reading of each observation is made ten times,
and the mean of these readings taken as the result.
The following observations of the intensity of the chemical action of light on July 8,
1864, may serve as an example of the detail of the determinations.
Solar time.
T.
Duration of
exposure,
Mean
reading,
R.
Tabulated
intensity
of strip,
Calculated
intensity,
n
Condition of
solar disk.
Amount of
cloud.
Barom.
Temperature.
Dry
bulb.
Wet
bulb.
h m
millims.
7 10 A.M.
18
96
1*00
0-055
Clouded over
8
7 50
15
93
1*03 .
0-068
Clouds
7
8 25
12
90
1-06
0-089
j>
9
9 0
10
76
1-20
0-12
jj
„
9 30
10
75
1-21
0-12
„
millims.
10 30
10
64
1*33
0-13
„
765-1
18-6 C.
13-9 C.
11 0
10
76
1*20
0-12
Clouded over
10
11 30
10
67
1-30
0-13
„
„
12 0
10
86
M0
0-11
„
18-7
13-3
12 30 p.m.
6
107
0-78
0-13
Light clouds
9
19-3
13-5
1 10
8
73
1-24
0-15
„
7
1 40
5
105
0-80
0-16
„
19-3
13*7
2 15
4
93
1-03
0-26
Unclouded ...
4
19-7
13-9
3 0
4
80
1-16
0-29
»
3
20-0
14-4
3 30
21 (with disk)
99
0-93
0-26
4 0
5
86
M0
0-22
n
21-1
14-4
4 30
8
76
1*20
0-15
1
5 0
11
66
1*31
0-12
6 10
60
116
0-66
0-011
»
”
KEGISTEATION OF THE CHEMICAL ACTION OE TOTAL DAYLIGHT.
617
IV. Concerning the accuracy and trustworthiness of the method.
The most satisfactory mode of testing the reliability and accuracy of the method of
measurement just described, is to compare the results of two series of independent
determinations of the chemical action of daylight, made simultaneously at the same
spot with the present arrangement and with the pendulum photometer, according to
the method described in the last memoir, upon which the present mode of measure-
ment is founded. For the purpose of making these comparisons, the strips of standard
photographic paper placed in the pendulum apparatus (see fig. 1 of last memoir) and
the pieces of the same material placed on the insolation-band in the exposing slide
(fig. 3, A) were simultaneously insolated, each for a known length of time, both instru-
ments being placed near one another in a position (on the roof of the laboratory of
Owens College, Manchester) having a tolerably free horizon. If the varying daily
intensities thus measured by the two methods are found to agree, we may conclude
that the unavoidable experimental errors arising from graduation, exposure, and reading
are not of sufficient magnitude materially to affect the accuracy of the measurement.
The intensity with the pendulum photometer was determined exactly as described on
pp. 158 & 159 of the above-cited memoir ; the time of exposure and the number of
vibrations were noted, the position at which the strip possessed a shade equal to that of
the normal tint was then read off, and the corresponding intensity obtained by dividing
the number found in Table II. of the above memoir by the number of the vibrations.
The intensity, according to the new method, was obtained by insolating the standard
paper in the exposing slide (fig. 3, A) for a known number of seconds, and then reading
off, by means of the arrangement shown in fig. 6, the position in millimetres on the
calibrated strip equal in shade to the exposed paper. The number found in the second
column of the Intensity Table, of the strip opposite to this position, when divided by the
time of exposure in seconds, gives the required intensity. In this way comparisons of
the working of the two modes of measurement have been made during four different
days. On each of these days a large number of simultaneous observations were made,
and on some of them two or more determinations were made with each instrument
immediately succeeding each other. An examination of the following Tables, giving
the results of these observations, shows that the agreement between the intensities
as obtained by the two methods is as close as can be expected.
618
PEOEESSOE EOSCOE ON A METHOD OF METEOEOLOGICAL
Simultaneous Measurements with Pendulum Instrument and New Photometer.
April 29th, 1864.
May 10 th, 1864.
Time.
Intensity.
Difference.
Time.
Intensity.
Difference.
Pendulum
instrument.
New photometer.
Pendulum
instrument.
New photometer.
h m
9 30 a.m.
10 0
11 0
11 5
12 30 p.m.
12 32
1 30
2 0
2 30
3 0
3 0
3 30
0-210
0-160
0-073
0-064
0-200
0-210
0-068
0-105
0-124
0-136
0-117
0-157
0-180
0-160
0-083
0-078
0-210
0-220
{!«}“4
0-105
J 0*1331
[ 0-133 j
0-144
0-114
0-182
-0-03
0-00
+ 0-010
+ 0-014
-0-01
+ 0-01
-0-04
0-00
+ 0-009
+ 0-008
— 0-003
+ 0-025
h m
9 0 A.M.
10 0
11 15
12 30 p.m.
1 1 0
2 30
2 33
4 30
0-093
0-100
0-130
0-220
0-100
0-105
0-115
0-0125
{S2}«»
0-110
0-150
0-250
f 0 099l o-lOO
\ 0-102 J u luu
/ 0-109 1 Q.JQO
1 0-096/ u
0-116
0-0106
-0*011
+ 0-010
+ 0-020
+ 0-030
0-000
—0-003
+ 0-001
-0-002
Simultaneous Measurements (continued).
June 8, 1864.
Intensity.
Time.
Pendulum
New
Difference.
Time.
photometer.
instrument.
h m
h m
10 40 A.M.
0-229
0-203
-0-026
9 50 A.M.
10 42
0-232
{S}0'233
+ 0-001
10 25
11 25
0-218
0-207
-0-011
10 40
11 27
0-225
0-217
-0-008
1 33 p.m.
0-205
0-231
+ 0-026
2 15
0-218
0-230
+ 0-012
11 45
2 17
0-224
0-233
+ 0-009
3 20
0-072
0-064
-0-010
3 22
4 0
0-077
0-039
0-068
0-048
-0-009
+ 0-009
12 15 p.m.
4 3
0-031
0-036
+ 0-005
12 45
1 30
2 21
2 46
July 16, 1864.
Intensity.
Pendulum
photometer.
New
instrument.
Difference.
{53}
PP
0-19
°‘14 I ft - or
0-13/ 0135
{
{53}
0-24
0*16
0-18
0-20
0*17
h0*21
0-17
f 0*24')
J 0*20
0-19
1 0-18 ,
h0-20 J
f0-17'
ft-
^0-205
0-145
0-13^1
III
0-13 J
0-00
-0-02
+ 0-02
+ 0-012
-0-025
+ 0-02
+ 0-008
The curves on figs. 7, 8, & 9, Plate XXVIII. exhibit these results graphically for the
first three days, and a glance at these curves show how closely the measurements made
REGISTRATION OF THE CHEMICAL ACTION OF TOTAL DAYLIGHT. 619
by the two methods agree. The black line represents the intensity as determined by
the pendulum instrument, the dotted line that obtained by the new photometer, the
abscissae giving the times of observation, and the ordinates the chemical intensity in
the terms of the unit above described. The mean chemical intensities, as observed on
the above days by the two methods, are represented by the following numbers, for the
definition of which the reader is referred to page 621.
Daily Mean Chemical Intensity.
Plate XXVIII. 1. Pendulum photometer. 2. New instrument.
Fig. 7, April 29, 1864 . .
. 62-0
62-3
Fig. 8, May 10, 1864 . .
. 41-3
43-3
Fig. 9, June 8, 1864 . .
, . 64-7
65-3
From these results the agreement of the two methods is well seen.
As a second test of the trustworthiness and availability of the method for actual
measurement, I give the following results of determinations, made at the same time and
on the same spot, by two observers with two of the new instruments. These determi-
nations, made with the two graduated fixed strips B and C (page 613), were conducted
in every way independently, so that the results serve as a fair sample of the accuracy
with which the measurements can be practically carried out.
Simultaneous Determinations made independently with two Instruments by two observers.
July 11, 1864.
July 15, 1864.
Time.
Chemical Intensity.
Time.
Chemical Intensity.
Instrument 1.
Strip B.
Instrument 2.
Strip C.
Instrument 1.
Strip B.
Instrument 2.
Strip C.
h
m
h
m
10
30 A.M.
0-16
0-14
10
0 A.M.
0-16
0-17
0-14
0-14
10
1
0-19
0-19
io’
31
0-14
0-15
11
0
0-049
0-046
0-12
0-13
11
1
0-049
0-046
io’
32
0-13
0-11
11
35
0-12
0-12
y
9
0-15
0-12
99
0-12
0-12
10
33
0-14
0-12
11
36
0-12
0-13
li
0
0-13
0-12
0-11
0-11
12
0
0-31
0*27
12*
30 p.m.
0-13
0-10
12
30 p.m.
0-31
0-29
0-13
0-12
12
31
0-38
0-37
99
0-14
0-13
12
32
0*33
0-31
0-14
0-12
12
33
0-35
0-32
\
’ 0
0-17
0-17
1
5
0-13
0-13
0-18
0-18
2
0
0-27
0-25
2
*30
0-057
0-060
0-27
0-25
0-068
0-070
3’
’lO
0-24
0-23
3’
30
0-059
0-057
3
11
0-21
0-24
0-067
0-062
3
12
0-18
0-23
3
*31
0-063
0-045
3
13
0-17
0-18
0-054
0-045
3
40
0-24
0*23
A
20
0*028
0-025
3
41
0-14
0-15
0-028
0-025
4
0
0-21
0-20
0-032
0-028
4
30
0-11
0-13
0-14
0-14
A
31
0-14
0-15
0-15
0-14
4’
32
0*16
0-14
620
PROFESSOR ROSCOE ON A METHOD OF METEOROLOGICAL
Figs. 10 & 11, Plate XXVIII. exhibit the daily curve of chemical intensity thus deter-
mined; the close agreement of the two curves for each day shows that the errors of
graduation, exposure, and reading do not materially affect the accuracy of the measure-
ments; whilst the values of the Daily Mean chemical intensities obtained from each
curve, viz. 42-0 and 4P7 for fig. 11, July 15, 1864 ; and 74'3 and 70'0 for fig. 10, July 11,
1864, confirm this conclusion.
V. Application of the Method to actual Registration.
A series of determinations of the varying intensity of the chemical action of total
daylight, made at Manchester on more than forty days, at the most widely differing
seasons of the year, extending from August 1863 to September 1864, serves to show,
in the first place, that the daily determination of the varying chemical intensity can
without difficulty be carried on ; whilst, secondly, they reveal a few of the many
interesting results to which an extended series of such measurements must lead. The
whole of the observations, with a few exceptions, were carried on in Manchester, upon
the roof of the laboratory of Owens College. As a rule, one observation was made
every half-hour ; frequently, however, when the object was either to control the measure-
ments, or to record the great changes which suddenly occur when the sun is obscured
or appears from behind a cloud, the determinations were made at intervals of a few
minutes or even seconds. Sometimes, when the sky was overclouded, or when no
great changes in the light occurred, the observations were made once every hour. On
most of the days employed for observation, the temperature, atmospheric moisture,
barometric pressure, varying amount of cloud, and the condition of the sun’s disk were
noted.
The curves given on Plate XXIX. serve to exhibit these same results graphically, the
abscissae representing the hours of the day (solar time), and the ordinates giving corre-
sponding chemical intensity expressed in terms of the unit above described.
Consecutive observations were carried on each day for nearly a month, from June 16 to
July 9, 1864 ; the labour thus incurred was found to be comparatively light, so that, when
all the preliminary arrangements are made, the daily measurements take up but a small
portion of the attention and time of one observer. From the results of these measurements
the great difference becomes perceptible which often exists between the chemical inten-
sity of neighbouring days ; examples of this variation are seen on PlateXXIX. figs. 12
& 13, for June 27th and 28th, and on figs. 14 & 15, for June 29th and 30th. The tabular
results show that the amount of chemical action generally corresponds to the degree of
cloud or sunshine, as noted in the observation. Irregular changes in the chemical action
are, however, observed on some days (as on March 19, 1864, fig. 16), on which the sun
shone continuously, and these are to be mainly attributed to the variation in the amount
of cloud passing at the time of observation. In several cases, when no apparent change
in the amount of light as affecting the eye could be noticed, a considerable and sudden
alteration in the chemical intensity occurred. This was clearly seen on September 26,
REGISTRATION OE THE CHEMICAL ACTION OE TOTAL DAYLIGHT. 621
1864, when the whole sky was apparently unclouded throughout the day; at 9h 25' a.m.
the chemical intensity was found to be (M3; at 10h, without any visible change in the
light, the chemical action sank to 007, and continued at this point for more than half
an hour, rising again to (Ml at 11 o’clock. That this diminution of the chemical
activity arises from the presence of mist, or of suspended particles of water imper-
ceptible to the eye, is rendered probable by the very powerful absorptive action which
a light haze or mist exerts upon the chemical rays. Thus on March 18, 1864, the
action at 8l1 a.m., when a light mist obscured the sun, amounted to 00026, whereas the
normal action for that day and hour, with an unclouded sky, is twenty-five times as
large. It is scarcely necessary to remark that on this occasion the ratio of decrease of
visible luminosity was not nearly so great. The same absorptive action of mist is well
seen in the following measurements on September 27 and 28, 1864.
September
27, clear sun.
September 28,
, sun obscured by haze.
Time.
Intensity.
Weather.
Time.
Intensity.
Weather.
h m
10 0 A.M.
0-13
Clear sky and direct sun.
h m
10 0 A.M.
0-016
Hazy.
10 30
0-17
10 30
0-039
„
11 0
0-18
11 0
0-053
„
11 30
0-13
11 30
0-075
„ [pearing.
12 40 p.m.
0-16
„
12 0
0-042
Sunshine, haze gradually disap-
1 10
0-13
12 45 p.m.
0-056
1 40
0-17
: i o
0-053
„
2 10
0-14
„
1 30
0-10
Haze gone.
2 15
0-12
For the purpose of expressing the relation of the sums of all these various hourly
intensities, giving the daily mean chemical intensity of the place, a rough, but sufficiently
accurate method of integration may be resorted to. This consists simply in cutting
the curves out in strong homogeneous paper or cardboard, and in determining in each
case the weights of the paper enclosed between the base-line and the curve. A por-
tion of the paper of given size is cut out between every four or five curves, and the
small variations in weight caused by irregularity in the thickness of the paper thus
allowed for.
In the following Table the numbers are compared with the action, taken as 1000,
which would be produced by light of the intensity 1 acting uniformly throughout the
twenty-four hours.
4 Q
MDCCCLXV.
622
PROFESSOR ROSCOE ON A METHOD OE METEOROLOGICAL
Daily Mean Chemical Intensities at Manchester, 1863-64.
(Intensity 1*0 acting for 24 hours = 1000.)
Date.
Intensity.
Date.
Intensity.
Date.
Intensity.
1863.
1864.
1864.
August, 26
40-5
March 19
36-8
June 28 ..
26-6
27
29-8
April 19
78-6
29
26-7
Sppt. 4
41-8
20
85-3
30
64-4
16 .
30-8
June 16
100-7
July 1
61-5
23
12*4
17
47-2
19-1
24
18-7
18
118-7
4
51-2
25
18-1
20
50 '9
5
76-2
28
29'1
21
99-0
6
78-9
Dee. 21
3-3
22
119-0
7
39-1
4*7
23
81-4
8 1
72-2
25
83-0
9
83-6 !
27
83-0
Sept. 26
48-8
The remarkable differences observed in the chemical intensity on two neighbouring
days is shown on fig. 17, in which the curves for the 20th and 22nd June 1864 are
represented. The integrals for these days are 50 ‘9 and 119’; or the total chemical
action on the 20th and 22nd June is in the ratio of 1 to 2*34.
The chemical action of daylight at Manchester at the winter and summer solstice,
and the vernal and autumnal equinoxes, is clearly seen by reference to the curves on
fig. 18, in which the actions on September 28, 1863, December 22, 1863, March 19, 1864,
and June 22, 1864, are represented graphically. These days were chosen out from
amongst the observations made near the required periods, as being days upon which the
sun shone most brightly, and as therefore giving the nearest approach to the maximum
actions for the several periods in question. The integral for the winter solstice is 4*T,
that of the vernal equinox 36'8, that of the summer solstice is 119, and that of the
autumnal equinox 29 T. Hence if the total chemical action on the shortest day be
taken as the unit, that upon the equinox will be represented by 7, and that upon the
longest day by 25. From these numbers, as well as from the curves (fig. 18), it is seen
that the increase of chemical action from December to March is not nearly so great as
that from March to June. With the small amount of experimental data which we as
yet possess upon this subject, it is useless to attempt to give an explanation of the
probable cause of this difference ; suffice it to say that it does not appear to be mainly
produced by the absorptive action exerted by the direct sunlight in passing through the
different lengths of the columns of air which the rays have to traverse on the days in
question.
In carrying out a regular series of meteorological observations upon the variation of
mean daily chemical intensity at any spot, a fair average result may be obtained by a
much smaller number of observations than is necessary when the object is to indicate
the rapid changes occurring in the intensity. Thus, for instance, if determinations had
been made on the following days once every two hours, viz. at 8b, 10h a.m., 12h, 2h, 4h,
REGISTRATION OF THE CHEMICAL ACTION OE TOTAL DAYLIGHT.
623
and 6h P.M., instead of about every fifteen minutes, the numbers for mean chemical
intensity would have been —
Date.
Mean Chemical Intensity.
From 26 observations.
From 6 observations.
] 863, August 26
40-5
43-0
„ Sept. 4
41-8
42-7
1864, April 20
85-3
96-3
As examples of simultaneous determinations made in different localities, I give the
results of observations made by myself in Heidelberg, lat. 49° 24' N., on July 4, 1864,
and near Dingwall in Rossshire, lat. 57° 35' N, on September 27, 1864, compared with
the results of observations made in Manchester, 53° 20' N. latitude, by my assistant.
The curves for Heidelberg and Manchester are given in fig. 19, those of Dingwall and
Manchester on fig. 20. The integral giving the mean action at Heidelberg on July 4
is 160, that at Manchester on the same day being 51 -2; so that the chemical action
at Manchester and Heidelberg was on July 4 in the ratio of 1 to 3T2. The integral for
Dingwall on September 27 is 66-4, whilst that of Manchester is 49-5 ; or the ratio of
chemical action at Manchester and Dingwall on the day in question was 1 to T34.
From these observations it would appear that the chemical action at Manchester is
smaller than accords with the latitude of the place. This is easily accounted for by the
absorptive action exerted by the atmosphere of coal smoke in which the whole of South
Lancashire is constantly immersed. Indeed, from the frequent occurrence in Man-
chester of dull or rainy days, and of fogs or mists, it would be difficult to choose a spot
more unsuited to the prosecution of experiments on the chemical action of light.
From the integrals of daily intensity giving the mean chemical action for each day,
the mean monthly or yearly chemical intensity of the place of observation can, in like
manner, be ascertained ; so that, should this method of measurement prove capable of
general adoption, we may look forward to obtaining in this way a knowledge of the
distribution of the chemically active rays over the surface of our planet analogous to
that which we already possess respecting the heating rays.
624
PROFESS OR ROSCOE ON A METHOD OE METEOROLOGICAL
Tables giving the Results of the Measurement of Daily Chemical Intensity
in 1863-64, at Manchester, Heidelberg, and Dingwall.
Daily Chemical Intensity, Manchester, 1863.
August 26, 1863.
Barom. = 746 millims.
September 4, 1863.
Barom. = 756 millims.
Solar time.
Chemical inten-
sity of light.
Sun’s disk.
Solar time.
Chemical inten-
sity of light.
Sim’s disk.
h m
h
m
7 3 A.M.
0-060
Unclouded.
7
45 A.M.
0-062
Unclouded.
7 33
0-038
Cloudy.
8
15
0-075
7 45
0-092
Unclouded.
8
45
0-083
Ditto, hazy.
8 15
0-077
9
20
0-098
Unclouded.
8 45
0-070
Unclouded, hazy.
9
40
0-097
,,
9 15
0-086
Unclouded, haze.
10
0
0-166
99
9 45
0-97
10
30
0-115
99
10 30
0-133
10
45
0-173
99
10 50
0-187
11
0
0-165
99
11 10
0-148
11
30
0-135
Cloud.
11 13
0-191
11
42
0-079
11 30
0-229
11
50
0-128
Unclouded.
11 50
0-203
Light clouds.
11
57
0-137
,,
12 0
0-160
12
10 p.M.
0-072
Clouded.
12 20 p.m.
0-210
Unclouded.
12
26
0-159
Unclouded.
12 40
0-075
Cloudy.
12
29
0-143
1 0
0-062
99
12
45
0-165
99
1 22
0-062
1
20
0-099
Light clouds.
1 40
0-094
Light clouds.
1
21
0-105
„
2 20
0-069
Clouds.
2
25
0-149
Unclouded.
3 0
0-021
2
45
0-038
Cloudy.
3 30
0-016
Clouded over.
3
0
0-024
99
4 0
0-016
n
3
30
0-035
99
4 30
0-018
n
4
0
0-040
Cloudy, rain.
5 0
0-009
»
5
0
0-035
Clouds.
5 30
0-004
5
30
0-016
6 0
0-010
”
August 27, 1863.
September 16, 1863.
Barom. = 745 millims.
Barom. = 767 millims.
8 5 A.M.
0-026
Cloudy.
9
0 A.M.
0-059
Cloudy.
8 33
0-068
Clouds.
9
35
0-120
Light clouds.
9 0
0-041
10
15
0-078
Overclouded.
9 45
0-039
10
45
0-077
„
10 30
0-098
Light clouds.
11
15
0-041
„
11 0
0-146
11
45
0-104
11 4
0-132
Unclouded.
12
0
0-103
t
11 30
0-115
Light clouds.
12
35 p.m.
0-080
„
12 0
0-059
Cloudy.
1
0
0-086
„
12 30 p.m.
0-122
Unclouded.
2
0
0-091
,,
1 0
0-057
Clouds.
2
40
0-093
„
1 30
0-078
Clouded over.
3
20
0-037
,,
2 0
0-159
Sunshine.
4
0
0-027
Rain.
2 20
0-155
4
45
0-034
Clouds.
3 0
0-027
Clouded over.
6
0
0-007
„
3 20
0-051
Light clouds.
3 50
0-066
Unclouded.
4 10
0-004
Overclouded.
4 30
0-002
Thunder-storm.
REGISTRATION OE THE CHEMICAX ACTION OF TOTAL DAYLIGHT.
G25
Daily Chemical Intensity, Manchester, 1863 (continued).
September 23, 1863.
Barom. = 738 millims.
Solar time.
sity of light.
Sun’s disk.
h m
9 0 A.M.
0-026
Overclouded.
9 30
0-054
Light clouds.
10 0
0-063
Overclouded.
10 30
0-042
11 0
0-065
Light clouds.
11 30
0-077
Sun, clouds.
12 0
0-013
Overclouded.
12 20 p.m.
0-031
12 45
0-041
1 0
0-056
n
1 50
0-062
2 10
0-038
2 30
Rain.
Heavy rain.
4 0
0-01
September 24,
1863.
Barom. = 744 millims.
9 0 A.M.
0-068
Light clouds.
9 30
0-069
10 10
0-105
Sunshine.
10 40
0-016
Overclouded.
11 20
0-038
Light clouds.
11 40
0-015
Overclouded.
12 0
0-033
Light clouds.
12 30 p.m.
0-046
12 45
0-087
Unclouded.
12 46
0-099
99
1 0
0-110
99
1 55
0-088
Light clouds.
2 10
0-068
Unclouded.
2 40
0-042
Overclouded.
3 0
0-021
}j
3 30
0-014
j
Rain.
5 0
0-014
Overclouded.
September 25, 1863.
Barom. = 753 millims.
9 0 A.M.
0-042
Overclouded.
9 40
0-077
Unclouded, hazy.
10 20
0-035
Light clouds.
11 0
0-042
11 30
0-037
1 50 p.m.
0-031
Overclouded.
2 20
0-055
Light clouds.
2 21
0-075
Unclouded.
2 22
0-081
”
September 25, 1863 (continued).
Barom. = 753 millims.
Solar time.
Chemical inten-
Sun’s disk.
sity of light.
h m
2 50 p.m.
0-065
Unclouded.
3 15
0-050
Light clouds.
3 20
0-064
Unclouded.
3 50
0-063
3 50
0-063
5 0
0-012
Overclouded.
September 28,
1863.
Barom. = 755 millims.
9 20 a.m.
0-045
Light clouds.
10 20
0-108
Unclouded.
10 21
0-108
10 55
0-101
99
10 56
0-106
99
11 20
0-125
99
11 48
0-133
Overclouded.
12 20 p.m.
0-047
1 0
0-052
99
1 40
0-055
Light clouds.
2 30
0-099
Unclouded.
2 31
0-094
99
3 0
0-080
99
3 1
0-079
3 40
0-072
»
3 50
0-059
4 0
0-044
4 10
0-043
4 30
0-037
Light clouds.
”
5 0
0-019
5 30
0-004
December 21,
1863.
Barom. = 760 millims.
11 0 a.m.
0-013
Clouds.
11 10
0-011
99
11 20
0-012
Hazy.
11 30
0-014
99
11 43
0-019
Unclouded.
12 0
0-003
Rain.
12 15 p.m.
0-018
Clouds.
12 30
0-010
Overclouded.
1 0
0-017
Light clouds.
1 30
0-013
Overclouded.
2 0
0-066
2 30
0-0066
3 0
0-0084
3 30
0-0017
”
626
PROFESSOR ROSCOE ON A METHOD OF METEOROLOGICAL
Daily Chemical Intensity, Manchester, 1863-64.
December 22, 1863.
Barom. = 761 millim-'.
April 19, 1864 (continued).
Barom. = 758 millims.
Solar time.
Chemical inten-
sity of light.
Sun’s disk.
Solar time.
Chemical inten-
sity of light.
Sun’s disk.
h m
h m
9 10 a.m.
0-0077
Hazy.
10 0 A.M.
0-29
Unclouded.
9 40
0-0057
Cloudy.
10 46
0-20
10 20
0-011
i9
11 0
0-33
11 20
0-020
12 0
0-25
99
11 40
0-025
.
1 0 P.M.
0-26
11 50
0-026
Unclouded.
2 14
0-15
11 55
0-028
2 45
0-20
12 0
0-023
Light clouds.
3 15
0-13
„
12 30 p.m.
0-020
Hazy.
3 45
0-11
12 35
0-032
Unclouded.
4 20
0-10
„
1 0
0-029
Hazv.
4 50
0-081
„
1 30
0-017
Unclouded.
2 0
0-017
2 30
0-0066
”
April 20, 1864.
Darom. = /oy minims.
March 19. 1864.
6 50 a.m.
0-067
Hazy.
Barom. = 753 millims.
7 45
0-17
Unclouded.
—
8 15
0-22
Hazy.
8 0 A.M.
0-0026
Misty.
8 45
0-22
„
9 0
0-070
Unclouded.
9 20
0-35
„
9 40
0-120
10 0
0-26
Unclouded.
10 25
0-080
10 50
0*30
,,
10 45
0-13
11 15
0-16
11 0
0-13
11 30
0-17
11 15
0-080
11 40
0-19
11 35
0-10
99
11 50
0-17
11 45
0-11
12 0
0-16
„
11 55
0-10
12 30 p.m.
0-16
12 0
0-12
12 45
0-14
12 5 p.m.
0-12
1 1
0-18
„
12 10
0-12
99
1 30
0-14
„
12 33
0-14
2 5
0-23
1 0
0-12
„
2 46
0-12
Cloudy.
1 35
0-045
3 13
0-11
2 20
0-11
3 30
0-10
„
3 30
0-069
Light clouds.
4 15
0-091
„
4 40
0-039
5 5
0-094
„
6 0
0-007
5 30
0-060
„
6 5
0-041
6 50
0-014
”
April 19, 1864.
7 30
0-0037
„
Barom. = 758 millims.
7 50 a.m.
0-10
Unclouded.
9 25
0-22
”
REGISTRATION OF THE CHEMICAL ACTION OF TOTAL DAYLIGHT.
627
Daily Chemical Intensity, Manchester 1864.
June 16th, 1864.
Barom.=758‘3 millims
Mean Temp. Dry bulb 17°‘9.
„ Wet bulb 12°-9C.
June 18th, 1864.
Barom.=761 millims.
Solar time.
Chemical
intensity
of light.
Amount
of cloud.
Sun’s disk.
Solar time.
Chemical
intensity
of light.
Amount
of cloud.
Sun’s disk.
h m
h m
6 25 A.M.
0-039
Clouded over.
7 50 A.M.
0-19
Unclouded.
7 0
0-019
99
8 40
0-30
99
7 30
0-10
Clouds breaking.
9 10
0-19
Clouds.
8 0
0-13
„
9 55
0-19
8 30
0-15
Light clouds.
10 45
0-13
9 0
0-13
Clouded over.
11 30
0-19
99
9 30
0-24
Unclouded.
12 35 p.m.
0-33
Light clouds.
10 0
0-38
„
1 30
0-38
99
10 30
0-29
„
3 0
0-21
,,
11 0
0-38
„
4 0
0-22
Unclouded.
11 30
0-35
„
6 30
0-033
Clouds.
12 0
0-22
Light cloud.
8 0
0-0079
99
12 30 p.m.
0-37
1 0
0-31
June 20th, 1864.
Mean Temp. Dry bulb 19°-5.
1 30
0-26
„
Barom. =763-8 millims. „
Wet bulb 15°-9 C. j
2 0
0-24 1
0-23 }
”
8 0 A.M.
0-14
Light clouds.
2 30
0-17
Clouds.
8 45
0-14
Clouds.
3 0
0-13
Unclouded.
9 15
0-099
99
3 30
0-15
Light clouds.
9 55
0-094
99
4 0
0-10
„
10 30
0-16
99
4 30
0-052
Clouded over.
11 0
0-12
5 0
0-045
„
11 30
0-15
99
5 30
0-087
Light clouds.
12 0
0-13
99
7 15
0-030
„
12 15 p.m.
0-13
99
8 15
0-010
„
12 45
0-16
'
99
8 40
0-0027
„
1 0
0-15
99
0-11
June 17th, 1864.
Mean Temp. Dry bulb 20° '5.
1 O'/
2 10
0-074
99
Barom.=760-9 millims.
„
Wet bulb 17°T C.
2 45
0-075
,,
3 15
0-044
6 40 A.M.
0-053
Clouded over.
3 50
0-053
Clouded over.
7 10
0-086
4 30
0-031
7 50
0-18
)}
5 30
0-030
Rain.
8 30
0-11
Light clouds.
7 0
0-010
„
Q ft
o. 1 1
y u
9 30
U 11
0-28
”
June 21st,
, 1864.
Mean Temp. Dry bulb 16°-1.
9 55
0-13
Clouded over.
„
Wet bulb 11°-1 C.
10 25
0-045
})
11 10
0-15
}J
6 40 A.M.
0-12
11 40
0-12
7 15
0-13
Light clouds.
12 10 p.m.
0-14
)}
7 45
0-074
„
12 30
0-14
8 30
0-080
„
1 0
0-35
9 30
0-21
Unclouded.
1 35
0-18
)}
10 0
0-27
Light clouds.
2 0
0-12
10 30
0-27
2 40
0-059
)}
11 10
0-33
5
3 10
0-062
11 30
0-29
Sun shining.
3 40
0-027
12 0
0-072
8
Clouds.
4 20
Rain.
12 30 p.m.
0*22
8
Unclouded.
628
PEOEESSOB EOSCOE ON A METHOD OE METEOBOLO GTCAL
Daily Chemical Intensity, Manchester, 1864 (continued).
June 21st, 1864 (continued). Mean Temp. Dry bulb 16°T.
„ Wet bulb 11°T.
Chemical
Amount
Sun’s disk.
Solar time.
intensity
of light.
of cloud.
h m
1 0 P.M.
0-29
6
Unclouded.
1 35
0-28
6
Clouds.
2 45
0-21
4
Unclouded.
3 15
0-24
3
Hazy sunshine.
4 15
0-13
Unclouded.
5 30
0-038
Clouds.
6 10
0-031
„
7 40
0-012
”
June 22nd, 1864.
Mean Temp. Dry bulb 17°‘6.
Barom. =761 millims.
»
Wet bulb 13°-5 C.
8 0 A.M.
0-15
Clouded over.
Rain.
8 45
0-017
10
Clouded over.
9 15
0-22
6
Clouds.
10 0
0-22
9
„
10 30
0-21
8
„
11 0
0-19
8
,,
11 30
0-45
6
Unclouded.
12 15 p.m.
0-49
5
1 30
0-28
3
„
1 50
0-27
5,
2 0
0-26
2
2 30
0-38
,,
3 0
0-17
’ 5
Light clouds.
3 30
0-17
o
99
4 0
0-16.
3
Unclouded.
5 0
0-15
1
6 0
0-068
Clouds.
June 23rd, 1864.
Mean Temp. Dry bulb 15°T.
Barom. =757"6 millims.
”
Wet bulb ll°-6 C.
7 0 A.M.
0-090
10
Heavy rain.
9 20
0-18
10
Clouded over.
10 10
0-18
9
11 30
0-18
9
Rain.
12 0
0-21
10
Clouds.
1 0 P.M.
0-22
7
Rain.
3 0
0-16
3 40
0-17
6
Unclouded.
4 35
0-12
8
Clouded.
5 0
0-093
9
1 ”
June 25th, 1864.
Mean Temp. Dry bulb 16°'7.
Barom. =761-2 millims.
„ Wet bulb 13°-4.
7 45 A.M.
0-055
10
Clouded over.
8 30
0-14
10
„
10 10
0-27
10
„
11 0
0-18
10
„
12 0
0-27
10
„
12 30 p.m.
0-22
”
June 25th, 1864 (continued). Mean Temp. Dry bulb 16°-7.
Barom. =761-2 millims. „ Wet bulb 13-4.
Chemical
Amount
Solar time.
intensity
of light.
of cloud.
Sun’s disk.
h m
1 0 P.M.
0-16
Clouds.
1 45
0-33
Clouded over.
2 30
0-23
8
Unclouded.
3 10
0-13
10
Clouded over.
5 15
0-10
6 30
0-037
”
June 27
th, 1864.
Mean Temp. Dry bulb 16°-4.
Barom. =765'2 millims.
”
Wet bulb 12°-0 C.
7 45 A.M.
0-15
4
Light clouds.
8 30
0-22
4
Unclouded.
9 10
0-11
8
Clouds.
9 30
0-25
7
Unclouded.
10 0
0-12
6
Clouds.
10 40
0-34
4
Unclouded.
11 30
0-11
9
Clouded over.
12 0
0-21
7
Unclouded.
115 P.M.
0-050
9
Clouded over.
4 30
0-17
1
Unclouded.
5 7
0-15
1
„
5 30
0-092
1
„
6 0
0-020
”
June 28th, 1864.
Mean Temp. Dry bulb 15°-0.
Barom. =763-2 millims.
”
Wet bulb 13°-4C.
7 30 A.M.
0-031
10
Clouded over.
8 40
0-043
10
„
9 SO
0-15
10
10 20
0-060
10
11 0
0-037
10
Rain.
11 30
0-034
10
,,
12 30 p.m.
10
,,
2 30
0-095
10
-
June 29th, 1864.
Mean Temp. Dry bulb 13o,0.
Barom. =759-2 millims.
Wet bulb ll°-4 C.
7 40 A.M.
0-11
10
Clouds.
8 30
0-13
10
„
9 40
0-042
10
„
10 20
0-044
10
„
11 20
0-047
„
11 35
0-026
„
12 0
0-022
„
12 30 p.m.
0-040
„
1 15
0-018
„
2 20
0-013
,,
3 0
Rain.
4 0
0-028
Clouds.
5 0
0-014
”
REGISTRATION OF THE CHEMICAL ACTION OF TOTAL DAYLIGHT.
629
Daily Chemical Intensity, Manchester, 1864 (continued).
June 30th, 1864. Mean Temp. Dry bulb 12°-6.
Barom.=758 millims. „ Wet bulb 12°T.
July 4th, 1864 (continued).
Barom. =759-5 millims.
Mean Temp. Dry bulb 20° -3.
„ Wet bulb 11 °-8.
Solar time.
Chemical
intensity
of light.
Amount
of cloud.
Sun’s disk.
h m
12 0
0-065
9
Rain.
12 30 p.m.
0-070
9
„
1 0
0-097
8
„
1 30
0-090
8
„
2 0
0-14
8
„
2 30
0-14
Clouds.
3 0
0-34
Unclouded.
3 30
0-25
5
„
4 0
0*11
7
Clouded.
4 30
0-095
7
„
5 0
0-074
6
„
5 30
0-072
6
6 0
0-056
6
„
6 30
0-067
2
Sunshine.
7 0
0-043
0
Unclouded.
7 30
0-023
0
”
July 5th, 1864.
Mean Temp. Dry bulb 14° -0.
Barom. =761-6 millims. „
Wet bulb 10° -7.
8 10 A.M.
0-12
10
Clouds.
8 30
0-10
10
„
9 0
0-033
10
„
9 30
0-14
10
„
10 0
0-11
10
„
10 30
0-077
10
„
11 0
0-14
10
„
11 30
0-15
10
„
12 0
0-18
10
„
12 30 p.m.
0-12
10
„
1 0
0-10
10
»
1 45
0-32
7
Light clouds.
2 15
0-13
10
Clouded over.
2 45
0-28
6
Unclouded.
3 30
0-25
6
Clouds.
4 0
0-18
6
Light cloud
4 30
0-26
6
„
5 0
0-072
7
„
5 30
0-093
6
6 0
0-067
4
Clouds.
7 30
0-035
4
Unclouded.
July 6th, 1864.
Mean Temp. Dry bulb 17°-6.
Barom. =765’3 millims. „
Wet bulb 13 -4.
7 30 A.M.
0-058
1
Hazy.
8 0
0-083
1
„
8 30
0-10
3
„
9 0
0-077
7
Clouds.
9 30
0-20
7
Hazy.
10 15
0-13
4
„
10 45
0-078
10
Clouded over.
11 20
0-071
6
Light clouds.
11 50
o-io
. 7
”
Chemical
intensity
Amount
of cloud.
Sun’s disk.
h m
7 15 A.M.
8 15
9 10
10 0
11 0
11 30
12 0
12 30 p.m.
1 45
3 0
4 0
4 30
5 20
6 10
0-021
0-10
0-21
0-060
0-37
0-12
0-46
0-077
0-090
0-061
0-075
0 054
0-010
Clouded over.
Sunshine cloud.
Clouds.
Sunshine cloud.
Clouds.
Unclouded.
Clouded over.
Rain.
Light clouds.
Sun shining.
July 1st, 1864.
Barom. =758-2 milli
Mean Temp. Dry bulb 14° -6.
„ Wet bulb 11°-1.
8
15 A.M.
0-067
9
Clouded over.
9
5
0-11
4
Light clouds.
9
40
0-12
9
10
0
8
Rain.
10
30
0-17
Light clouds.
11
0
0-19
7
Clouds.
11
45
0-086
Clouded over.
12
30 p.m.
0-040
1
0
0-20
Sunshine.
2
15
0-25
5
Unclouded.
3
45
0-085
Clouded.
4
30
0-063
5
30
0-050
”
July
2nd, 1864.
Barom. =752 millims.
8
10 A.M.
0-042
10
Rain.
10
0
10
Rain.
12
0
0-028
3
45 p.m.
0-071
Fair, clouded.
4
20
0-046
4
50
0-043
Rain.
July 4th, 1864.
Mean Temp. Dry bulb 20° -3.
Barom. =
759'5 millims. „
Wet bulb ll°-8.
7
30 A.M.
0-076
8
Clouded.
8
0
0-11
6
”
8
30
0-077
9
9
0
0-041
10
Rain.
9
30
0-023
10
Clouded over.
10
10
0-055
9
10
30
0-056
9
11
0
0-038
9
Rain.
11
30
0-034
10
”
4 R
MDCCCLXV.
630
PROFESSOR ROSCOE ON A METHOD OE METEOROLOGICAL
Daily Chemical Intensity, Manchester, 1864 (continued).
July 6th, 1864 (continued). Mean Temp. Dry bulb 17°-6.
July 8th, 1864 (continued). Mean Temp. Dry bulb 19°-6.
Barom, =765-3 millims.
,. Wet bulb 13 -4.
Barom. =765*1 millims.
,, Wet bulb 13°-8.
Chemical
Chemical
Amount
Solar time.
intensity
of cloud.
Sun’s disk.
Solar time.
intensity
of cloud.
Sun’s disk.
of light.
of light.
b m
h m
12 30 p.m.
0-22
3
Light clouds.
12 0
0-11
Clouded over.
1 0
0*21
6
„
12 30 p.m.
0-13
9
Light clouds.
1 30
0-17
9
„
1 10
0-15
7
„
2 0
0*28
7
„
1 40
0-16
2 30
0-36
7
„
2 15
0-26
4
Unclouded.
3 0
0*15
„
3 0
0-29
3
3 30
0-17
4
„
3 30
0-26
„
4 0
0-21
Unclouded.
4 0
0-22
4 30
0-24
4
Light clouds.
4 30
0-15
1
5 15
0-092
5 0
0-12
1
6 30
0-063
4
”
6 10
0-011
”
July 7th, 1864.
Mean Temp. Dry bulb 16°-4.
July 9th, 1864.
Mean Temp. Dry bulb 15°-5.
Barom. = 764-7 millims.
”
Wet bulb 13°-2.
Barom. =764-1 millims.
»
Wet bulb ll°-7.
7 30 A.M.
0-040
10
Clouds above.
8 0 A.M.
0-060
O
Hazy,
1 8 0
0-058
10
„
9 0
0-15
8 30
0-10
10
„
10 0
0-14
9 15
0-079
10
„
11 0
0-18
Unclouded.
9 45
0-073
10
„
12 20 p.m.
0-15
10 10
0-069
10
„
1 30
0-23
„
10 45
0-056
7
„
2 30
0-22
11 30
0-020
7
„
3 30
0-22
„
12 0
0-055
9
„
4 30
0-14
12 30 p.m.
0-021
10
„
5 30
0-10
„
1 0
1 45
0-12
0-064
9
„
2 25
3 0
0-022
0-15
10
7
Light clouds.
September 26th, 1864.
| 3 30
4 0
0-092
0-070
Clouded over.
8 50 a.m.
0-11
Cloudless sky.
4 30
0-11
„
9 25
0-13
5 0
0-10
Clouds.
10 0
0-070
99
7 20
0-025
10 30
11 0
11 30
0 071
0-11
0-12
99
1 July 8th, 1864..
Mean Temp. Dry bulb 19°-6.
99
99
Barom. =765-1 millims.
Wet bulb 13°-8.
12 10
0-10
99
12 40 p.m.
0-11
99
7 10 A.M.
0-055
8
Clouded over.
1 5
0-15
99
7 50
0-068
7
Clouds.
1 55
0-17
99
8 25
0-089
9
„
2 30
0-12
9 0
0-12
„
3 0
0-096
9 30
0-12
„
3 40
0-078
99
10 30
0-13
„
4 10
0-056
99
ill 0
0-12
10
Clouded over.
4 45
0-038
99
11 30
0-13
”
5 15
0-018
REGISTRATION OE THE CHEMICAL ACTION OF TOTAL DAYLIGHT.
631
Daily Chemical Intensity, Heidelberg, Dingwall, and Manchester, 1864.
July 4, 1864. — Heidelberg.
September 27, 1864. — Dingwall, N.B. (continued).
Solar time.
Chemical
intensity
of light.
Amount
of cloud.
Sun’s disk.
Solar time.
Chemical
intensity
of light.
Amount
of cloud.
Sun’s disk.
h m
h m
6 56 A.M.
0-072
Clouded.
10 23 A m.
0-22
Unclouded.
7 1
0-170
Unclouded.
10 30
0-18
Haze.
8 6
0-208
Clouds.
10 35
0-16
„
8 21
0-206
Unclouded.
10 50
0-13
Cloud}-.
8 50
0-244
5?
11 25
0-16
Clouds.
9 21
0-290
„
11 26
0-15
„
9 40
0-394
2
„
12 45 p.m.
0-24
Unclouded.
9 42
0-470
2
„
2 37
0-19
„
10 23
0-475
2
„
2 45
0-13
Clouds.
10 35
0-590
2
,,
2 58
0-18
Unclouded.
11 30
0-620
„
3 57
0-066
Clouded.
11 49
0-60
12 18 p.m.
0-52
1 5
0-516
September 27, 1864. — Manchester.
2 21
0-248
Clouded.
3 5
0-300
Unclouded.
8 50 a.m.
0-13
Unclouded.
3 50
0-270
„
9 30
0-16
4 30
0-126
Overclouded.
10 0
0-13
4 50
0-163
Unclouded.
10 40
0-18
5 25
0-124
0
”
10 50
0-18
”
11 30
0-13
y>
September 27, 1864. — Dingwall, N.B.
12 0
0-098
Cloud.
12 40 p.m.
0-16
„
9 16 A.M.
0-18
Unclouded.
1 10
0-13
„
9 26
0-17
„
1 40
0-17
„
9 36
0-16
„
2 10
0-14
10 0
0-17
„
2 55
0-12
„
10 5
0-19
„
3 40
0-081
„
10 10
0-19
”
4 20
0 052
1 ”
Fh£b. Irons. HDCCCIS^ Jto SXHH
_L
i j
T=j
J
I
■ i - -
it
!
1
:
;
ii
iv
±j
v. | |v|'"|
JF
!
■20
■is
■is
■17
■IS
■15
■14-
■13
■n
■ii
u>
. V
1J
'ii
►
_2J
—
—
-
up
~ i lkt
-
!
'[ \
iu
_L
_L
— U
4-4
V
4-
=t
t
—r
+4-
; .
V
A
v
1.
-4-
~-H-t
v
A-
_l_
-f
L
\
V
_|
±J
r t"
v
\
A
_J
1 • T
%
v.
3:
—ii
4
'
v
—
-L
tj H \\
sf
h-
:$s
N
'
4..
,
\
V
_L
1
..
'
sN
IS
0-
— A
lightt
i
;v
=E
S
j
V;
;roi
Os
- >
tv
\
¥ H — 1 — T — r
\'
A
O'
x.
i' ’ll
| '
k
A
vv
si.
■\
s
—
Ti
i
0
n\
i i r
1
4
t-T
|h
\
1
.
TE
rt
S\\
i
1
vs
■os
■os
07
■06
T
TT
i
.
V
i_L
a i
Nu
V
*
i
® — i—
vf
M
j
\V
> 1
\
T 1
N,
=k
s
.
M
\v
i i i
L
; 1
.
'0
r.
"T
\
i
r
0
S
kNk
T
Os
pp
: '
r — |
VN
'1
7
—
1
J
Y
T
1 |
’ I
T
i
it
,
~
"I
P"
,\
in'
, . ;
"T0i
^ i
;
ii
Oi
’
;
r
L:
t
...
J
■
1
l:
L
■ J 50
40 £0 6(7 70
5(7 00 750
110 120
130
L
20
30 40
0 G
0 7
0 SO
90
100
no no
ISO
Phi Trtms.lPDCCCCW Flouts JSK
634
MR. W. H. FLOWER ON THE CEREBRAL COMMISSURES
Its fibres principally connect, across the middle line, the parts of the cerebral hemi-
spheres forming the inner wall of the middle horn of the ventricle, especially the folded
part constituting the hippocampus major. As its free edge forms the hinder boundary
of the region called the “psalterium” in human anatomy, the fibres composing it may
be distinguished as the “ psalterial fibres” of the corpus callosum. At a little distance
behind and rather lower than the point of the rostrum of the corpus callosum, is the
very distinct oval outline of the section of the white “anterior commissure” (F), and
between this and the under surface of the corpus callosum, and prolonged into the con-
cavity of the genu, is a portion of the inner wall of the hemisphere (G) closing the
lateral ventricle towards the middle line, and with the corresponding portion of the
opposite side forming the median septum which divides the two cavities from each
other, as will be better seen in the transverse section. This important region Professor
Huxley has distinguished as the “septal area”*.
To return to the upper arched border of the ventricular aperture. The middle part,
which when united to the corresponding portion of the other hemisphere constitutes
the “ body of the fornix” (K), is composed of a considerable number of white fibres
closely adherent posteriorly to the under surface of the body of the corpus callosum, and
running in a longitudinal direction. Tracing these fibres forwards, a small round white
cord (L) is seen to pass down from them behind the anterior commissure, constituting
the part commonly spoken of as the “ anterior pillar ” of the fornix, but which, to avoid
confusion, had better be designated as the “column” of the fornix ( Columna fornicis,
Reichert). The further course of this into the corpus albicans and optic thalamus need
not be detailed here. But a large portion of the fibres (I) running forwards from the
body of the fornix do not pass down into these cords, being continued above the anterior
commissure, and then curve downwards in front of that structure to join the inner wall
of the anterior lobe of the hemisphere. For these fibres the name of “ precommissural
fibres ” has been suggested by Professor Huxley. The presence of the precommissural
fibres, as well as that of much grey matter, gives to the lower part of the septal area a
much greater thickness than the upper part (to which the name of “ septum lucidum ”
is applied) possesses. But the two divisions of the area are perfectly continuous in
structure, the upper thin part also containing fibres prolonged from the fornix, radiating
forwards and upwards to the under surface of the corpus callosumf .
Posteriorly the fibres of the fornix, following the border of the aperture they encircle,
change their longitudinal direction, and gradually turn outwards, downwards, and finally
forwards, and even slightly inwards. Although in their anterior and middle portions the
fibres of the fornix run at right angles with the fibres of the corpus callosum, this change
of direction in their posterior part brings them parallel to, and allows them to blend with,
the transverse fibres of that body. The prominent sharp free margin of the ventricular
aperture formed by the “ posterior pillars ” of the fornix is called “ corpus fimbriatum ”
* Lectures at the Royal College of Surgeons, Medical Times and Gazette, March 5th, 1864.
t See Solly ‘ On the Human Brain,’ 2nd Edit. 1847, p. 261.
OE THE MAESUPIALIA AND MONOTEEMATA.
635
(M). A little way external and parallel to this, on the surface of the hemisphere, is a
deep sulcus, corresponding in direction and extent with the hinder third of the ventricular
aperture. This is the “ dentate ” or “ hippocampal ” sulcus (Q). It terminates above
under the posterior end of the corpus callosum. If the cortical grey matter of the hemi-
sphere is traced from the external border of the hemisphere towards the ventricular
aperture, it will be found to dip down into this sulcus, and rising again to the surface to
terminate abruptly just external to the corpus fimbriatum. The free border in which it
terminates, lying between the “ hippocampal sulcus ” and the “ corpus fimbriatum,” is
called the “ fascia dentata ” (P), its surface being generally somewhat notched or indented
at' intervals. The cerebral wall folded inwards at the sulcus just described, forms a cor-
responding projection in the cavity of the ventricle called the “hippocampus major.”
The relation of some of the parts above mentioned will be better understood by a
reference to Plate XXXVI. fig. 2. It is drawn from a vertical transverse section of the
human brain, at the point indicated by the line drawn across Plate XXXVI. fig. 1, viz.,
through the middle of the anterior commissure. B is the corpus callosum, passing from
hemisphere to hemisphere, across the bottom of the great longitudinal fissure*. As its
fibres pass outwards from the middle line, they curve slightly upwards before separating
to radiate throughout the medullary substance of the hemispheres. Immediately under-
neath the corpus callosum lie the cavities of the hemispheres or “ lateral ventricles,” com-
pletely separated from each other in this section by a septum (G), attached above to the
under surface of the corpus callosum, and below resting on the small transverse “anterior
commissure” (F). This part, the “septal area” of the former section, may be demonstrated
to consist throughout of two lateral portions, applied closely together in the middle line
below, but in the upper part slightly separated, the interval constituting the fifth ventricle,
or ventricle of the septum lucidum. The lower part of the septum, much thicker than
the septum lucidum, contains the precommissural fibres of the fornix with much grey
matter interposed. It seems never to have received any special name, or to have been
sufficiently distinguished from the septum lucidum, although it is the most constant, and
therefore important division of the septal area, as will be shown hereafter. The grey
masses (B, R) forming the outer boundaries of the ventricles are the “ corpora striata.”
The anterior commissure is seen as a small cylindrical bundle of white fibres (F) passing
between the corpora striata.
The true nature of these parts cannot be perfectly understood without a glance at their
development. This is a subject confessedly still involved in some obscurity. I follow,
however, the observations of F. Schmidt, who has given a detailed and apparently truthful
account of the process^. Without entering into previous changes, it may be stated that
each hemisphere consists, in a very early condition, of a hollow thin-walled body, with a
fissure (O) in its inner surface, leading to the cavity within (Plate XXXVI. fig. 3, 1).
* “ — the cross portion of white substance which lies between the hemispheres at the bottom of the longi-
tudinal fissure,” Qttain and Shaepey’s ‘ Anatomy,’ 5th edit. vol. ii. p. 464.
f Zeitschrift fur Wissenschaftliche Zoologie, vol. xi. (1861) p. 43.
4 S 2
636
ME. W. H. FLOWER ON THE CEREBRAL COMMISSURES
Through this a portion of the pia mater (afterwards developed into the choroid plexus)
enters. The fissure is at first perpendicular in direction. In front of it (at G) the two
hemispheres are united across the middle line, immediately behind it (A) they are con-
nected with the parts formed by the second cerebral vesicle, the subsequent optic thalamus
and crus cerebri. The last-named point (the crus or “ hirnstiel”) forms a pivot around
which the whole hemisphere curves itself as development proceeds. The fissure under-
goes a corresponding change of form and direction. The anterior edge becomes its
upper convex border. The upper end gradually becomes depressed until it is finally
the lowest part, and the characteristic form of the ventricular aperture is already recog-
nized at this early age (Plate XXXYI. fig. 3, III). The point of union between the
hemispheres is still confined to the part immediately in front of the anterior end of the
fissure, the “ septal area.” About this time the wall of the hemisphere commences to
undergo a folding upon itself, producing certain definite grooves or sulci on the outer
surface, and corresponding elevations upon the interior. At a very early period an
arched sulcus (bogenfurche) appears parallel to the upper border of the fissure, marking
off an arched convolution or gyrus between it and the fissure, the “ marginal arch”
( randbogen , Schmidt). It is the hinder part of this groove which afterwards forms the
“hippocampal sulcus.” Into the further development of the convolutions and sulci it
is unnecessary to enter. A more important subject in connexion with the present com-
munication is the mode of formation of the corpus callosum, the fornix, and adjacent
parts. Kolliker* has given so good an abridgement of Schmidt’s views, that I have
thought it best to follow pretty closely his words.
The convolutions of the hemispheres are distinctly seen from the third month to
consist of two layers, an external with perpendicular fibres, which at a later period con-
stitutes the grey or cortical substance of the convolutions, and an inner layer with fibres
running horizontally. The fibres of the inner layer, constituting the medullary substance
of the hemispheres, are found already in the third month, before the corpus callosum
exists, to converge towards two points ; first, towards the crus ( hirnstiel , A), where they
form the so-called stabJcranz ; and secondly, towards a point situated immediately above
the place of union of the two hemispheres. This last arrangement of fibres is the first
indication of the radiation of the corpus callosum ( balkenstrahlung ). It is at this
spot (B) that in the fourth month the horizontal fibres break through the cortical
substance and unite with the corresponding fibres of the opposite hemisphere.
This is the commencement of the corpus callosum, which in its earliest form (see
Plate XXXVI. fig. 3, IV) is a very small nearly cylindrical commissure, situated in the
“marginal arch ” immediately above the most anterior part of the ventricular aperture.
In order to indicate more closely the relation of the marginal arch to the corpus callo-
sum, it is to be noticed that the former separates into two parts, a lower division imme-
diately bordering the ventricular aperture, consisting only of horizontal or antero-pos-
terior fibres, without the cortical layer, and an upper division possessing both layers.
* Entwicklungsgeschichte des Menschen und der hoheren Thiere, p. 237, Leipzig 1861.
OF THE MARSUPIALIA AND MONOTREMATA.
637
Now the corpus callosum breaks through just at the limit between these two divi-
sions, and by its further growth backwards, the upper division comes to lie on its outer
surface and is converted into the stria alba Lancisi and stria obtecta of the corpus cal-
losum, and into the fascia dentata of the hippocampus major; whilst the inferior or
inner arch, with its longitudinal fibres, forms the fornix and septum ( scheideivand ).
The fornix is thus, as was known to Arnold and Retzius, a transformation of the upper
margin of the transverse fissure. The lower margin of the fissure is formed into the
taenia semicircularis or stria cornea, which, as is well known, is connected at each end
with the extremities of the fornix. It will be seen from the preceding observations that
the anterior perpendicular part of the fornix is originally united with the corresponding
part of the other side, and the body of the fornix developes itself out of the uppermost
part of this spot, adjoining the primitive corpus callosum. Lower down the parts sepa-
rate and then resolve themselves into the columnae fornicis, or anterior crura, and the two
halves of the septum lucidum, the ventricle of which is thus no primitive formation. In
this part also originates, not by growing together from opposite sides, but by histological
differentiation, the anterior commissure (F), which is evident a short time before the
corpus callosum. The septum lucidum and body of the fornix, in the beginning very
small, gradually increase in extent with the development of the corpus callosum.
According to Schmidt, the opinion formerly entertained that the genu of the corpus
callosum was the part first formed, and that the hinder part developed afterwards, is not
correct. The rudimentary corpus callosum on its first appearance already contains the
elements of all its subsequent parts, as from the very first, fibres radiate from it into the
hinder and middle, as well as the anterior lobes, and the intimate connexion of the
former with the posterior crura of the fornix can already be recognized. It increases,
with the rest of the hemisphere, chiefly in longitudinal extent, spreading both backwards
and forwards from the point of its first appearance, but principally in the former direc-
tion. The curved part in front, called the genu, is not formed until the end of the fifth
month, and about a month later, the thickening and extension of the hinder end over
the corpora quadrigemina gives the permanent form to this part of the brain.
I will next proceed to trace the modifications of the parts of the brain above indicated,
in certain of the placental mammalia. The preparations from which the figures are
taken were all made in the same manner as that adopted in the case of the human brain,
viz., (I.) a vertical longitudinal section in the middle line, exhibiting the inner surface
of a single (the right) hemisphere, the thalamus opticus and crus having been removed
so as to show clearly the whole surface with the parts forming the upper boundary of
the ventricular aperture; (II.) a vertical transverse section through the middle of the
anterior commissure.
The Sheep. — In the longitudinal section of the sheep’s brain (Plate XXXVII. fig. 1),
the elongated narrow corpus callosum (B) is seen lying in a line nearly horizontal, or
corresponding with the long axis of the hemisphere ; slightly concave in the middle
638
ME. W. H. FLO WEE ON THE CEEEBEAL COMMISSIJEES
above, with a thickened posterior end (E) turned somewhat downwards, and a distinct
genu (C) and rostrum (D) in front. The latter has a smaller proportional development
than in the human brain. On the other hand, the slightly projecting posterior fold
observed in the human corpus callosum is prolonged forwards as a thin layer of transverse
fibres (N) arching across the under surface of the longitudinal fibres of the fornix, and
ending in no abrupt edge in front. The difference in the form and extent of this part
of the great transverse commissure may be clearly seen to depend upon the difference in
the form, and more extensive proportions of the parts that have to be brought into rela-
tion to each other by it, viz. those forming the inner wall of the descending cornu of the
lateral ventricle. At a considerable distance below the anterior part of the corpus cal-
losum the small anterior commissure (F) is seen, with the wide septal area (G) in front
of and above it. The portion of this part to which the term “ septum lucidum ” can
be applied, is reduced to a small strip beneath the anterior third of the corpus callosum,
exactly defined below and in front by the extent of the rostrum of that body. The
greater part of the septum is formed by a thick layer, consisting of a great development
of the precommissural fibres of the fornix, associated with much grey matter. The small
white column (L) of the fornix is seen passing down behind the anterior commissure.
The ventricular aperture is less regularly curved than in man, being bent almost at a
right angle. Above and behind it is seen a broad corpus fimbriatum (M), behind which
the abrupt termination of the cortical substance of the hemisphere in the fascia dentata
(P) is very distinctly seen. The regularly curved hippocampal sulcus (Q) ends beneath
the hinder end of the corpus callosum, the grey matter of the fascia dentata being con-
tinued superficially round its extremity into that of the next succeeding gyrus.
In the transverse section (Plate XXXVII. fig. 2), at the bottom of the deep longitu-
dinal fissure, is seen the corpus callosum (B), a transverse white band of moderate thick-
ness, and slightly arched upwards externally, where its fibres radiate out in the medullary
substance of the hemisphere. The anterior commissure (F) is readily recognized near
the lower part of the section. The cavities of the lateral ventricles are somewhat tri-
angular in form and bounded above by the under surface of the corpus callosum,
towards the middle line by the septum, and externally by the corpora striata. The
septum obviously consists of two halves, one belonging to each hemisphere, but more or
less joined together in the middle line. The upper part (septum lucidum) is extremely
thin, and here the absence of union between the two halves allows the existence of a
minute cavity, the fifth ventricle. The lower and larger part is very thick, with rounded
outer surface. It contains much grey matter, with white longitudinal fibres externally.
Within it, near the middle line, on each side, can be seen two bundles of white fibres,
standing nearly perpendicularly and slightly diverging from each other below ; they are
the upper part of the columns of the fornix.
The most essential deviations in the commissures of this brain from those of Man con-
sist in the reduction of the rostrum of the corpus callosum and the septum lucidum, and
the augmentation of the inferior thick part of the septal area and of the psalterial fibres.
OF THE MARSTJPIALIA AND MONOTREMATA.
639
The Rabbit. — Plate XXXVII. fig. 3 represents the inner surface of the cerebral hemi-
sphere of a rabbit. The corpus callosum (B) is no longer horizontal in its general
direction, but, like the upper margin of the hemisphere, is elevated at the posterior end.
In front it is slightly thickened, but the rostrum is scarcely perceptible. Although
this commissure in its median section appears elongated from before backwards, it is
very thin from above downwards. The inferior layer of transverse (psalterial) fibres
are well developed, and, except posteriorly, distinct from the main part of the great
transverse commissure. The septal area is large in extent. The anterior commissure
is proportionally larger than in man or in the sheep. The hippocampal sulcus, corre-
sponding with the large size of its internal projection into the ventricle, is deep, and
prolonged for some distance beneath the hinder end of the corpus callosum. The hollow
for the reception of the optic thalamus and corpora quadrigemina is very large, and the
fascia dentata (P) lying in it very broad. The smooth inner wall of the hemisphere
shows no other sulcus than that of the hippocampus.
The transverse section (Plate XXXVII. fig. 4) shows the corpus collosum at the
bottom of the longitudinal fissure, curving up at the two extremities, in consequence
of the form of the lateral ventricles. The anterior commissure is of actual greater
depth in the section than the corpus callosum. Between the two is the septum, now
only represented by the thick lower portion, very considerably increased in develop-
ment. The thin upper part, together with the fifth ventricle, has entirely disappeared
with the rostrum of the corpus callosum.
In the Two-toed Sloth ( Cholcepus didactylus), Plate XXXVII. fig. 5, the same parts
can be recognized, though somewhat changed in proportions. As compared with the
sheep especially, the whole hemisphere is greatly shortened in the antero-posterior
direction, and a greater shortening still has taken place in the corpus callosum. Instead
of bearing, as in the sheep, the proportion to the hemisphere of 53 to 100, it is but as
32 to 100. It rises at the posterior part, where it is slightly enlarged. The anterior
end is simple and obtusely pointed, without a trace of the reflected rostrum. The
anterior commissure is considerably larger, relatively to the hemisphere, than in the
sheep. The ventricular aperture is nearly vertical in general direction. At the poste-
rior edge of the body of the fornix there is a considerable thickening, caused by the
transverse psalterial fibres of the corpus callosum. The hippocampal sulcus may be
traced upwards to near the hinder end of the corpus callosum ; it then makes a sudden
curve backwards, and almost immediately after another nearly equally sudden bend
forwards, then arches over the end of the corpus callosum, and gradually approaching
the upper surface of that body, at about its middle disappears in the lower margin of
the callosal gyrus. Thus a thin portion of the dentate gyrus (fascia dentata) is continued
over the hinder edge, on to the upper surface of the corpus callosum. In its principal
part the gyrus itself is longitudinally grooved by a shallow sulcus, anterior and parallel
to the hippocampal sulcus. The characteristic indentations are faintly indicated on the
posterior edge.
640
ME. W. H. FLOWER ON THE CEREBRAL COMMISSURES
The transverse section (Plate XXXVII. fig. 6) shows the corpus callosum curving up
at the outer extremities owing to the upward development of the lateral ventricles, as
in the rabbit, and in the foetal condition of the higher mammals. The corpora striata
(K, K) are very large. The anterior commissure exceeds in vertical depth the corpus
callosum. The septum, broad below where it rests on the anterior commissure,
diminishes above to a narrow edge, where it touches the under surface of the corpus
callosum; but there is no part which can properly be called septum lucidum. On
each side of the middle line are seen the vertical white fibres, forming the commence-
ment of the columns of the fornix.
Plate XXXVII. figs. 7 & 8 are taken from the brain of the Common Hedgehog
(Erinaceus europceus). The transition from the Sloth’s brain to this is easy, although it
presents a wide difference from that of the Eabbit. The inner surface of the cerebrum
shows no trace of any sulcus, except the deep one of the hippocampus (Q), which is
placed very near the hinder border of the truncated hemisphere, and terminates a little
way behind and below the posterior end of the corpus callosum. The last named body
is extremely reduced in size, its length being but one fifth that of the entire hemisphere.
Its obliquity is so much increased that its general direction is rather vertical than hori-
zontal. The psalterial fibres form a distinct projection (N) in the section closer to the
body of the corpus callosum than in the two previously described brains. The septal
area is much reduced, and the anterior commissure increased in bulk. The great size of
the olfactory ganglion is very remarkable.
The transverse section shows a corresponding simplicity, and agrees in all its essential
characters with that of the Sloth. The oblique position of the corpus callosum gives its
section an apparent thickness, which it would not possess if divided, as in the higher
mammals, at a right angle to the plane of its upper surface.
These are examples of some of the modifications of the commissural apparatus of the
cerebral hemispheres among the placental mammals. They might be considerably multi-
plied, but they are sufficient for the purpose of affording a basis of comparison with the
same parts in the Marsupials and Monotremes.
Before entering upon this part of the subject, it may be desirable to give an outline of
the present condition of knowledge upon it. A reference to the works of comparative
anatomists who wrote before the year 1887, shows that up to that period no important
distinction had been suspected to exist in the cerebral organization of the placental and
the implacental mammals. In the Philosophical Transactions of that year, however,
appeared the memoir of Professor Owen “ On the Structure of the Brain in Marsupial
Animals,” in which was announced the absence in these animals, of the “ corpus callo-
sum and septum lucidum.” A transverse commissure between the hemispheres superior
to the anterior commissure is described, but called by Professor Owen “fornix” or
“ hippocampal commissure.” Of this it is stated, “ This commissure may, nevertheless,
be regarded as representing, besides the fornix, the rudimental commencement of the
OP THE MAESUPI ALI A AND MONOTEEMATA.
641
corpus callosum; but this determination does not invalidate the fact that the great
commissure which unites the supraventricular masses of the hemispheres in the Beaver
and all other placentally developed Mammalia, and which exists in addition to the
hippocampal commissure, is wanting in the brain of the Wombat: and as the same
deficiency exists in the brain of the Great and Bush Kangaroos, the Vulpine Phalanger,
the Ursine, and Mauge’s Dasyures, and the Virginian Opossum, it is most probably the
characteristic of the marsupial division of Mammalia.” The relatively large size of the
anterior commissure in the marsupials is referred to in the paper as worthy of notice,
as also is the proportionally very large size of the hippocampi majores.
The description given in this important memoir was subsequently reproduced in the
Cyclopaedia of Anatomy and Physiology, art. Marsupialia, and it was shown that the
same peculiarity also existed in the Monotremata, and therefore was characteristic of the
whole implacental division. In the paper by the same author “ On the Characters,
Principles of Division and Primary Groups of the Class Mammalia”*, the Subclass
Ly encephala (“ loose” or “ disconnected” brain), equivalent to the Implacentalia, are
characterized as having “ the cerebral hemispheres but feebly and partially connected
together by the ‘ fornix’ and 4 anterior commissure,’ while in the rest of the class a part
called ‘corpus callosum’ is added, which completes the connecting or commissural
apparatus’^. The views of Professor Owen have been adopted without hesitation or
qualification, in this country at least, and have been incorporated in almost every text-
book on Anatomy and Physiology subsequently published. The same has been the case
to a great extent upon the continent, and what is more important, they have received
confirmation apparently from original dissections of several of the marsupials by the
editors of the third edition of Cuvier’s ‘ Anatomie Comparee,’ MM. F. Cuvier and
Laurillard (1844), and in the case of the Echidna by MM. Eydout and Laurent
(Voyage de la Favorite, 1839).
But expressions of dissent have also been raised. Leuret, speaking of the brain of
* Proc. Linn. Soc. 1858.
t [The necessity of doing full justice to the labours of one who has made this subject so peculiarly his own,
will excuse my quoting the following succinct account of the distinctive characteristics of the views of this
eminent anatomist, as set forth in his most recent publication bearing upon the question.
“ In investigating and studying the value and application of the cerebral characters of Man in the classifica-
tion of the Mammalia, I have been led to note the relations of equivalent modifications of cerebral structure to
the extent of the groups of mammals respectively characterized by such conditions of brain. The Monotremes
and Marsupials, which offer numerous extreme modifications of the limbs, all agree in possessing a brain in
which there is no connecting or commissural mass of fibres overarching the lateral ventricles of the cerebrum.
The surface of this part shows, however, a few symmetrical convolutions in Echidna and Macropus, especially
the largest species ; but in the majority of marsupials the hemispheres are smooth. The £ corpus callosum,’ or
great commissure, makes its appearance abruptly in the Eats, Shrews, Bats, and Sloths, which in general
organization and powers are next the ‘ loose-brained ’ marsupials or Ly encephala : but this commissure is
associated with a similarly smooth unconvolute cerebrum, and with so small a size of the cerebrum as leaves
uncovered the cerebellum and in most the optic lobes.” — Contributions to the Natural History of the
Anthropoid Apes, No. VIII., by Professor Owen, Trans. Zool. Soc. vol. v. part 4, 1865, p. 270. — April 1865.]
MDCCCLXV. 4 T
642
MR. W. H. FLOWER ON THE CEREBRAL COMMISSURES
the Kangaroo, says,* “ J’y ai vu bien manifestement nn corps calleux, situe entre les deux
lobes cerebraux, comme chez les antres mammiferes.”
Foville, in a note to p. 172 of his well-known treatise on the Nervous System (1844),
says, “ M. de Blainville a toujours sontenu l’existence du corps calleux chez les didel-
phes, et me l’a fait voir de la maniere la plus manifeste chez plusieurs de ces animaux.
II a si peu de volume qu’on s’explique facilement comment on a pu croire a son absence.”
F. J. C. MAYERf, speaking of the brain of the Common Opossum ( Didelphis virginiana),
says, “Das corpus callosum betreffend, so ist dasselbe ebenfallsund namentlich bei Didel-
phis vorhanden, nur schmal oder kurz, allerdings etwas schmaler oder kurzer, als bei den
Nagern, allein noch kurzer ist das corpus callosum beim Igel [hedgehog] wo es ebenfalls
nur ein vorderes schmales Markblatt bildet. Aber schon bei den Nagern treten der
Eingang in den dritten Ventrikel und der Sehhiigel hinter dem corpus callosum zu Tage,
am meisten aber bei dem Igel, und die Beutelthiere stehen nur zwischen beiden, den
Nagern und dem Igel in der Mitte, und es ist somit im Gehirne derselben keine abwei-
chende Organisation wahrzunehmen, welche mit der Geschlechtstheile etwa eine Parallele
liefern konnte”$.
The more detailed description of this structure in the brain of the same animal, given
by Pappenheim § in language remarkable for its precision, deserves to be quoted in full,
as it has received little attention from subsequent authors. It agrees in the main with
the observations recorded in this paper.
“ Mais je crois devoir m’occuper, avant tout, de la nature du corps calleux. C’est
une opinion tres-repandue, que ce corps n’existe pas chez les Marsupiaux. Cependant
les dessins et la description de M. Owen prouvent que ce corps a ete tres-bien vu par cet
anatomiste habile ; mais que, d’un cote, il n’a pas reconnu sa marche entiere, et que,
de l’autre, il a ete frappe par la situation de cette commissure, qu’il a consideree plutot
comme un fornix (voute a trois piliers). Comme cet organe se trouve dessine en partie
dans le paquet cachete que l’Academie a bien voulu me faire l’honneur d’accepter, je me
bornerai aujourd’hui a signaler quelques faits qui, rapproches de mes observations
anciennes, prouveront que le corps en question est bien un corps calleux.
“ 1°. La commissure dont je parle est situee en avant des couches optiques, la ou leur
* Anat. Comp, du Systeme Nerveux, t. i. p. 412 (1839).
t Neue Untersuchungen aus dem Gebiete der Anatomie und Physiologie. Bonn, 1842, p. 24.
t Professor Owen (Annals and Mag. Nat. Hist. vol. xvi. p. 101, 1845), in replying to Mater’s statement,
says, “The great transverse band or commissure which unites the two hemispheres, spanning from one to the
other above the lateral ventricle — which is plainly visible, as such, in the lowest Rodent or other placental mammal,
with the smoothest, and, to outward appearance, simplest brain, — this great commissure or corpus callosum, I
again affirm, after reiterated dissections, to be absent in all the known genera of Marsupials. If the narrow
transverse hand, which unites together the hippocampi majores, at the front part of the fornix, be regarded, as
I originally stated it might he, a rudiment of the ‘ corpus callosum,’ the comparative anatomist is at liberty to
apply that name to it.”
§ “ Notice preliminaire sur 1’ anatomie du sarigue femelle ( Didelphis virginiana ),” Comptes Rendus, tom. xxiv.
p. 186 (1847).
OF THE MAESUPIALIA AND MONOTKEMATA.
643
premier developpement s’opere, au-dessus de la commissure anterieure du cerveau.
Toutes ses fibres rayonnent au-dessus du corps strie, dans les hemispheres, ou elles se
terminent en faisceaux paralleles aux fibres des pedoncules cerebraux.
“ 2°. Elle s’allonge en avant dans un corps genouille, qui ne peut etre compare aux
pedoncules du fornix, lesquels entrent dans les couches optiques, tandis que ce dernier
corps rayonne dans les hemispheres.
“ 3°. Les fibres de cette commissure sont purement transversales, direction qui n’a
aucun rapport avec celles des fibres du fornix.
“4°. Les fibres du fornix ne s’etalent jamais dans les parois des ventricules; aussi
n’occupent-elles pas toute la longueur du ventricule lateral.
“ Cette commissure n’est done ni un fornix, ni un melange du fornix avec le corps
calleux.
“ La partie posterieure est composee de fibres accumulees en un faisceau tres-epais,
tandis que les fibres anterieures du corps calleux sont etalees dans une couche large, mais
extremement mince et tellement transparente, que l’on voyait a travers le corps strie.
Du reste, quand on ecartait les hemispheres, les fibres du corps calleux, etalees, se lais-
saient detacher facilement de l’autre substance blanche, sous forme de feuillet mince,
tapissant, pour ainsi dire, la paroi du ventricule lateral dans chaque hemisphere.
“ Les hemispheres etaient composes d’une maniere tres-simple, savoir ; des fibres des
pedoncules cerebraux, qui etaient les plus externes; des fibres de la commissure ante-
rieure, en avant et en dedans, et d’un feuillet appartenant au corps calleux, situe en
dedans du rayonnement des fibres du pedoncle ; tout autour, enfin, etait une couche
corticale tres-epaisse et peut-etre plus considerable que toutes les fibres blanches.”
Such are the main results of the researches of those anatomists to whom we are
indebted for all that is known upon the cerebral commissure of the Implacental Mam-
mals. I will next give an account of these structures as actually observed in several of
the leading types of the group, and afterwards discuss the relation which the conclusions
derived from the present examination (differing somewhat in method from those pre-
viously used) bear to the opinions most generally received.
Kangaroo. — Several specimens of the brains of both Macropus major and Macropus
Bennettii have been examined. They agree so closely in all essential points that one
description will suffice for either, unless otherwise specially stated.
On looking at the upper surface of the brain (Plate XXXVI. fig. 4), the two hemi-
spheres being partly separated, a transverse white band (B) is seen extending across the
bottom of the longitudinal fissure, roofing over the anterior portion of the third ven-
tricle, and occupying the same general position as the corpus callosum in the ordinary
mammal, but developed to a smaller extent even than in the Hedgehog. In a brain of
Macropus Bennettii it was found to cover, when still undisturbed by removal from the
cranial cavity or contracted by spirit, about half the optic thalamus, and to measure from
before backwards in the middle line, a quarter of an inch, or one-sixth of the entire
4 t 2
644
ME. W. H. FLOWEE ON THE CEEEBEAL COMMISSURES
length of the hemisphere. It is situated deeply in the great longitudinal fissure, is
thickened and most elevated posteriorly, where the margin, slightly and evenly concave,
crosses the cavity of the third ventricle (S), the peduncles of the pineal gland (T), and
the optic thalami (U). The anterior margin is also concave, but extremely narrow, the
white substance being continued on each side of a longitudinal median cleft for some
distance towards the front of the cerebral hemisphere, as if in this anterior part the two
lateral halves of the commissure had not been joined together in the middle line. On
close examination it is seen to be composed of fibres of which the general direction is
transverse, but on its upper surface can be distinguished a longitudinal median raphe,
and on each side of this a few longitudinal white fibres, corresponding to the “striee late-
rales” of other mammals.
On either side, the transverse fibres are lost beneath the overlapping grey matter
constituting the margin of the convolution of the corpus callosum, the “labia cerebri”
of some authors. To follow them further, the last named parts must be carefully
removed with the handle of a scalpel or some similar instrument, when a delicate broad
lamina formed by the lateral expansion of the narrow transverse band will come into
view, passing at first horizontally outwards and then curving upwards above the precom-
missural fibres of the fornix (I), the cavity of the lateral ventricle, and the corpus stri-
atum (R), and finally losing themselves in the medullary substance of the upper part of
the cerebral hemispheres. The fibres radiate extensively forwards and backwards but
forming a continuous lamina, posteriorly conterminous with those on the surface of the
hippocampus major, anteriorly becoming much more delicate, so much so, indeed, that
it is not easy to make a complete dissection of them without causing some rents, like
that on the left side shown in the figure, through which the cavity of the ventricle below
is exposed. This expansion of the transverse commissure in the hemisphere, though
described by Pappenheim in the Opossum, appears not to have been observed by Owen
in any of his dissections.
Plate XXXVIII. fig. 1 is a view of the inner surface of the right hemisphere of the
Great Kangaroo. The hemisphere is short, and deep from above downwards, obtusely
pointed in front and flattened or abruptly truncated behind. The temporal lobe is
largely developed. Several well-marked sulci are seen upon the surface of the hemi-
sphere. One of the most striking characteristics presented by this section is the
great development of the anterior commissure (F), far exceeding that seen in any
placental mammal. The form of its section is oval, with the long diameter nearly
vertical, or inclining slightly forwards at the upper end. It consists of firm, white,
transverse fibres, distinctly defined from the surrounding part, and forms a good
landmark to the adjoining structures, as about its homologies there can be no ques-
tion. At a very short distance above this is seen the section of the median part of
that transverse band before described (B). This is oval, elongated from before back-
wards, slightly arched on its upper border. Its anterior and posterior extremities are
rounded, the former is the narrowest. To the under surface of the latter, a body of
OP THE MARSTJPIALIA AND MONOTREMATA.
645
transverse fibres (N), almost equal in size to the upper portion of the commissure,
is intimately united. Beneath the anterior part of this, close to the middle line, a
distinct white cylindrical band of fibres is seen to pass down, behind and in close con-
tact with the anterior commissure, at first directed somewhat backwards and afterwards
downwards until it loses itself in the thalamus opticus. This evidently answers to one of
the columns of the fornix, its position being somewhat disturbed by the immense deve-
lopment of the anterior commissure. Between the superior transverse commissure (by
which name I propose for the present to call the part marked B) and the anterior com-
missure are some fibres continued forwards from above the anterior end of the ventri-
cular aperture, and mixed in this region with much grey matter, forming the greatly
reduced septal area (G). They curve forwards and downwards, encircling the anterior
half of the anterior commissure, and represent, doubtless, those designated as “ precom-
missural ” fibres in the higher mammals. The ventricular aperture is seen to occupy
its ordinary position. Its upper margin is formed by the edge of a broad white band,
corpus fimbriatum (M). On tracing this band forwards, it is found to be continuous
with the hinder edge of the whole of the upper transverse commissure. The superficial
grey layer (P) external to the corpus fimbriatum is readily recognized as the fascia den-
tata. This is bounded on the outer side by the hippocampal sulcus ; but in respect to
this sulcus a great peculiarity presents itself. On tracing it forwards, instead of stop-
ping short beneath the projecting posterior rounded end of the corpus callosum, as in
most, if not all placental mammals *, it is continued on, passing over the top in close
contact with the upper transverse commissure, and is not lost until it reaches the inner
surface of the anterior lobe, considerably in advance of both the upper and anterior
commissures. The remarkable disposition of this sulcus must be particularly noted in
reference to the nature of the commissure in close relation with it.
In the transverse section (Plate XXXVIII. fig. 2) the immense size of the anterior
commissure (F) is as conspicuously seen as in the longitudinal section. It occupies
one-fourth of the whole height of the brain in the middle line. Its fibres spread them-
selves outwards, the lower ones sweeping first slightly downwards, then curving up into
the white medullary substance of the middle of the hemisphere. The higher fibres,
taking a course more directly upwards, penetrate the grey matter of the corpora striata
(R R), which they here divide into two distinct masses, and finally reach the medullary
substance of the upper part of the hemisphere. Lying immediately upon the anterior
commissure, close to the median line, are two bodies, which, taken together, present a
surface broad from side to side, slightly concave above, nearly flat below, and rounded
off at the outer inferior angles. These consist mostly of grey substance, with some white
fibres, especially collected into two bands close to the median line (the roots of the
columns of the fornix). These bodies are the two lateral halves of the very much
thickened and depressed ventricular septum. Below they are in contact with the anterior
commissure, on each side with the cavity of the lateral ventricle, above with a white
* A partial exception was shown in the Two-toed Slotln
646
ME. W. H. ELOWEE ON THE CEEEBEAL COMMISSUEES
transverse band. This band, lying at the bottom of the great longitudinal fissure of
the cerebrum, is the one previously mentioned as the superior transverse commissure.
Traced outwards, its fibres, spreading into an extremely thin layer, form the upper
and inner boundary of the superior portion of the lateral ventricle. They have a regular
curve, outwards, upwards, and finally inwards, losing themselves in the medullary sub-
stance of the hemisphere at its upper and inner angle. Their internal concave border
is in contact with a fold of cortical grey matter, surrounding a deeply penetrating sulcus,
which from the very bottom of the longitudinal fissure runs outwards and then upwards
in the hemisphere, and which, as shown in the previous section, is continuous with the
hippocampal sulcus in the posterior part of the hemisphere. The lateral ventricle, as
seen in this section, is prolonged to a considerable height in the hemisphere, but other-
wise its relations are similar to those of the same part in the placental mammals.
Figs. 3 & 4, Plate XXXVIII. are taken from the brain of the Wombat ( Phascolomys
vombatus). In general form the cerebral hemispheres are more depressed and elongated
than those of the Kangaroo, and the temporal lobe obtains a comparatively slight
development. Corresponding with this general elongation, the ventricular aperture
and the surrounding parts have a wider curve backwards. The essential characters are,
however, precisely the same. The anterior commissure attains an equal magnitude.
The superior transverse commissure has the same form and relations, and the con-
tinuation of the hippocampal sulcus extends above it, though it is not prolonged to
quite the same extent on the anterior lobe. Seen in transverse section, the septum is
narrower from side to side.
The large carnivorous Marsupial, the Thylacine ( Thylacinus cynocephalus), so widely
separated in external characters from both the Kangaroo and Wombat, shows the same
general peculiarities of cerebral organization, but attended with a smaller development
of the superior transverse commissure, especially of its anterior part, and a greater reduc-
tion of the thickness of the interventricular septum (see Plate XXXVIII. figs. 5 & 6).
Dissections of the brains of Phalangista vulpina and of Didelphis virginiana have
yielded similar results, so that it may be presumed that the principle upon which the
cerebral commissures are arranged is uniform throughout the Marsupial Order.
Of the two genera of Monotremes, I have only had the opportunity of dissecting the
brain of one, the Echidna. This most remarkable brain, with its largely developed and
richly convoluted hemispheres, conforms in the main with the Marsupial type in the
disposition of the commissures, but in detail presents a still further deviation from the
ordinary mammalian form. As seen in Plate XXXVIII. fig. 7, the anterior commissure
is as large relatively as in the Marsupials. Above it is seen the section of the superior
transverse commissure, very much reduced in extent, and in which the two portions,
upper and lower, observed in the Kangaroo are no longer distinguishable. Its relations
to the hippocampal sulcus, to the ventricular aperture, to the columns of the fornix, to
the precommissural fibres, and to the lateral ventricles are however the same, so that
whatever parts of the placental mammalian brain are represented by this commis-
OF THE MABSUPIALIA AND MOXOTREMATA.
647
sure in the Kangaroo, are also represented by it, though in a reduced degree, in the
Echidna. Perhaps the greatest change is in the extreme reduction of the septum, as
best seen in the transverse section (Plate XXXVIII. fig. 8). In dissecting the brain
from above, the fibres of the superior commissure are found to spread out into a delicate
layer roofing in the ventricles quite to the anterior part of the hemisphere, as described
in the Kangaroo.
Having described the actual condition of an important and well-marked region of the
cerebrum in several members of the two great groups of the Mammalia, it now remains
to trace out the relation that the several structures entering into the formation of this
region bear to one another in each of the two groups. It will be necessary also to
inquire how far the results brought out by the present method of examination are in
accordance with the views generally received.
At the outset a distinct confirmation is afforded by the dissections recorded in this
paper, of the great fact, first observed by Professor Owen, that the brains of animals of
the orders Marsupialia and Monotremata present certain special and peculiar characters,
by which they may be at once distinguished from those of other mammals. The appear-
ance of either a transverse or longitudinal section would leave no doubt whatever as to
which group the brain belonged. In the differentiating characters to be enumerated,
some members of the higher section present a considerable approximation to the lower ;
but, as far as is known at present, there is still an interval between them unconnected
by any intermediate link.
The differences are manifold, but all have a certain relation to, and even a partial
dependence on, each other.
They may be enumerated under the following heads : —
1. The peculiar arrangement of the folding of the inner wall of the cerebral hemi-
sphere. A deep fissure, with corresponding projection within, is continued forwards
from the hippocampal fissure, almost the whole length of the inner wall. In other
words, the hippocampus major, instead of being confined as it is, at least in the higher
forms of placental mammals, to the middle or descending cornu of the lateral ventricle,
extends up into the body of the ventricle, constituting its inner wall.
2. The altered relation (consequent upon this disposition of the inner wall) and the
very small development of the upper transverse commissural fibres (corpus callosum).
3. The great increase fin amount, and probably in function, of the inferior set of
transverse commissural fibres (anterior commissure).
These propositions must now be considered a little more closely. Arguing from our
knowledge of the development of the brain in placental mammals (for of that of the
marsupials we have at present no information), it may be supposed that the first-
named is also first in order of time in the gradual evolution of the cerebral structures.
Before any trace of the budding out of the fibres which shoot across the chasm sepa-
rating the two hollow sac-like hemispheres, before the differentiation of a portion of the
648
MR. W. H. FLOWER ON THE CEREBRAL COMMISSURES
septal area into the anterior commissure, that remarkable folding of the inner wall, indi-
cated by the deep furrow on the surface and the corresponding rounded projection in
the interior, has already become distinctly manifest, and the future form of the ventri-
cular cavity, with its elevations and depressions, has been sketched out. Now the first
rudiment of the upper transverse commissure is found undoubtedly at the spot after-
wards situated near its middle — that part to which in the lowest placental mammals it
is almost entirely confined. This spot is situated a little way above and in front of the
anterior end of the ventricular aperture, at the upper edge of the region of adherence of
the two hemispheres (the future septal area). In the placental mammals this part is in
direct relation to the great mass of the internal medullary substance of the hemispheres,
which have to be brought into communication. In the Marsupial, on the other hand,
the prolonged internal convolution or hippocampus extending up to and beyond this
part, forms the inner wall of the hemisphere from which the fibres pass across, and it
is necessarily through the medium of this convolution, and following the circuitous
course of its relief in the ventricle, that the upper part of the hemisphere alone can be
brought into connexion.
Can this transverse commissure, of which the relation is so disturbed by the dispo-
sition of the inner wall of the hemisphere, be regarded as homologous with the entire
corpus callosum of the placental mammals 1 or is it, as has been suggested by Professor
Owen, to be looked upon as only representing the psalterial fibres or transverse com-
missure of the hippocampi'? Undoubtedly a large proportion of its fibres do come
under the latter category. But even if they should nominally be all so included, it is
important to bear in mind that we have still a disposition in the marsupial brain very
different from that which would remain in the brain of any placental mammal after the
upper and main part of the corpus callosum had been cut away. In the latter case the
commissure of a very small part of the inner wall of the hemisphere alone is left, that
part folded into the hippocampus. In the former there is a commissure, feeble it may
be, but radiating over the whole of the inner wall, from its most anterior to its posterior
limits. Granted that only the psalterial fibres are represented in the upper commissure
of the marsupial brain, why should the name of “ corpus callosum ” be refused to it 1
These fibres are part of the great system of transverse fibres bringing the two hemi-
spheres into connexion with each other ; they are inseparably mingled at the points of
contact with the fibres of the main body of the corpus callosum, and are only separated
from it in consequence of the peculiar form of the special portions of the hemisphere
they unite. Indeed, as mentioned before, they are not more distinct than is the part
called “ rostrum ” in front. And although they blend at each extremity with the fibres
of the diverging posterior crura of the fornix, they certainly cannot be in any sense
confounded with that body, the essential character of which is that it is a longitudinal
commissure consisting of two halves closely applied in the middle, but each composed
of fibres belonging to a single hemisphere only.
But is the main part of the corpus callosum of the placental mammal not also repre-
OF THE MAKSUPIALIA AND MONOTEEMATA.
649
sented by the upper and anterior part of the transverse band passing between the hemi-
spheres of the marsupial brain 1 The most important and indeed crucial test in deter-
mining this question, is its position in regard to the septum ventriculorum, and especially
the precommissural fibres of the fornix. Without any doubt in all marsupial and
monotreme animals examined (sufficient to enable us to affirm without much hesitation
that it is the character common to all) it lies above them, as distinctly seen in the trans-
verse sections. Moreover, passing outwards into the hemispheres, it overarches or forms
the roof of the lateral ventricles of the cerebrum. This is precisely the same relation-
ship as that which occurs in Man and all other mammalia.
The defective proportions of the part representing the great transverse commissure
of the placental mammal, which appears to me to result from, or, at all events, to be
related to the peculiar conformation of the wall of the hemisphere, must not lead to
the inference that the great medullary masses of the two halves of the cerebrum are by
any means “disconnected.” The want of the upper fibres is compensated for in a
remarkable manner by the immense size of the anterior commissure, the fibres of which
are seen radiating into all parts of the interior of the hemisphere. There can be little
doubt but that the development of this commissure is, in a certain measure, comple-
mentary to that of the corpus callosum. That it is not simply correspondent with the
large size of the olfactory ganglion, as Professor Owen has suggested, is shown by the
fact that in the Hedgehog and some other placental mammals this ganglion attains a
far greater proportionate volume than in many marsupials, and yet the commissure is
very considerably smaller.
In descending the series from Man to the Placental Mammals of lowest cerebral
organization, the great change in the condition of the corpus callosum has been seen to
be, the disappearance of the rostral portion, and the coincident greater development of
the posterior folded or psalterial portion ; the latter being connected with the relative
increase of the hippocampal region of the cerebrum. In the brain of the marsupial a
change of precisely the same nature is carried to an excess. There is, however, as far as
my observations show, no structure characteristic of the higher group which is absent in
the lower.
The step from the marsupial or monotreme brain to that of an animal belonging to
one of the lower vertebrate classes is very great. Indeed it is difficult to see in many of
the peculiarities of their brain even an approach in the direction of that of the bird.
We may allow that the diminution of the volume of the corpus callosum leads on to its
entire absence ; but in the great development of the anterior commissure is presented a
special characteristic of the lowest group of mammalia, most remarkable because it is
entirely lost in the next step of descent in the vertebrate classes. The same may be
said of the cerebral folding constituting the hippocampus major.
Plate XXXVI. figs. 5 & 6 are views of the brain of a Goose, corresponding to those
given of the various mammals. The smooth, thin, inner wall has no trace of that folding
upon itself which gives rise to the hippocampus major in the mammal. In this respect
mdccclxv. 4 u
650
MR. W. H. FLOWER ON THE CEREBRAL COMMISSURES
there is a vast difference from the brain of the marsupial. The ventricular aperture (0 0)
is extremely reduced. Its upper border may be properly compared to the fornix, and
the thickened part of the inner wall (G), above and in front of the small anterior com-
missure (F), evidently corresponds to the lower part of the septal area and precommissural
fibres, as well seen in the transverse section. The walls of the hemispheres are in close
apposition at this part, as the two lateral halves of the septum are in the mammals;
but a distinct band of fibres passing across the middle line from one hemisphere to the
other, above the anterior commissure, has never yet been satisfactorily demonstrated. The
homology of the minute and delicate transverse lamella of nerve-substance, described by
A. Meckel as situated above the ventricular aperture posterior to the anterior commis-
sure, is very questionable.
Great as is the difference between the placental and implacental mammal in the mode
and extent of the connexion between the two lateral hemispheres of the cerebrum, it is
not to be compared with that which obtains between the latter and the oviparous verte-
brate.
Description op the Plates.
All, except fig. 3, Plate XXXVI., are from original dissections. For convenience of
comparison the cerebral hemispheres are reduced to the same absolute length.
PLATE XXXVI.
Fig. 1. Inner surface of the right cerebral hemisphere, Human brain.
Fig. 2. Vertical transverse section (through the anterior commissure), Human brain.
Fig. 3. Development of the Human brain (after F. Schmidt). I. Sixth week. II. Eighth
week. III. Tenth week. IV. Sixteenth week. V. Sixth month.
Fig. 4. Brain of Kangaroo ( Macropus Bennettii) dissected from above, natural size. A
portion of the extremely delicate great transverse commissure (B) has been
removed on the left side to show the structures lying beneath it.
Fig. 5. Brain of Goose. Inner surface of right hemisphere.
Fig. 6. Brain of Goose. Vertical transverse section.
PLATE XXXVII.
Fig. 1. Brain of Sheep. Inner surface of cerebral hemisphere.
Fig. 2. Brain of Sheep. Vertical transverse section.
Figs. 3 & 4. Brain of Rabbit.
Figs. 5 & 6. Brain of Sloth ( Cholcepus didactylus).
Figs. 7 & 8. Brain of Hedgehog (Erinaceus europceus).
OF THE MARSUPIALIA AND MONOTREMATA.
651
PLATE XXXVIII.
Figs. 1 & 2. Brain of Kangaroo ( Macropus major).
Figs. 3 & 4. Brain of Wombat ( Phascolomys vombatus).
Figs. 5 & 6. Brain of Thylacine ( Thylacinus cynocephalus).
Figs. 7 & 8. Brain of Echidna ( Echidna hystrix).
Explanation of the Letters used in all the Figures.
A. Crus cerebri, divided between thalamus
opticus and corpus striatum.
B. Body of corpus callosum.
C. Genu of corpus callosum.
D. Rostrum of corpus callosum.
E. Splenium of corpus callosum.
F. Anterior commissure.
G. Septal area.
H. Septum lucidum.
I. Precommissural fibres.
K. Body of fornix.
L. Columns of fornix.
M. Corpus fimbriatum. Edge of posterior
crura of fornix.
N. Psalterial fibres of corpus callosum.
O. Ventricular aperture.
P. Fascia dentata.
Q. Hippocampal sulcus.
R. Corpus striatum.
S. Third ventricle.
T. Peduncles of pineal body.
U. Thalamus opticus.
V. Corpora quadrigemina.
Bub.
Tig
Tig. 3.
WS1 ?. ad.-nat. 3 eL ( wMpt/lv). 3)
EdmaM.WEams.I’.L.S. Sc.
Bui. Trane. MDOOCI ^T.BLaJx,7£mi.
^g-2.
Fig. 4.
Fig. 6.
Kg. 8.
HTH.T. adaiat. dA.
IEc3wiiiM.T,BIli£aiis,P.L.S. Sc.
Fh£U. Trane. MDCCCEXF. Rales WX HL
Tig.Z.
Tig'. 4
Tig. 6.
Tig.7.
'VOTE: SLti.Tiab. deL
Ectmia M.TOEa:mslT'JJ.S. 8c.
[ 653 ]
XIV. On the Sextactic Points of a Plane Curve.
By William Spottiswoode, M.A., F.B.S., &c.
Received June 15, — Read June 15, 1865.
The beautiful equation given by Professor Cayley (Proceedings of the Royal Society,
vol. xiii. p. 553) for determining the sextactic points of a plane curve, and deduced, as
I understand, by the method of his memoir “ On the Conic of Five-pointic Contact ”
(Philosophical Transactions, vol. cxlix. p. 371), led me to inquire how far the formulae
of my own memoir “ On the Contact of Curves ” (Philosophical Transactions, vol. clvii.
p. 41) were applicable to the present problem.
The formulae in question are briefly as follows : If U=0 be the equation of the curve,
H=0 that of its Hessian, and V =(a, b, c,f g, h)(x, y, zf= 0 that of the conic of
five-pointic contact ; and if, moreover, a, /3, y being arbitrary constants,
b=ux-\-fiy-\-yz,
□ = (y^U - U)d, + («B,U -- yBJJ)^ + (,3d,U - «d,U)b2, J '
then, writing as usual
BJJ=w, bJJ=w; ^H=^, B,H=r,
^i=vlw1—u'2, . . Jf=v'w'—u1u', . .
vy — w(3=X, wot — uy—gj, u\ 3 — vu—»,
the values of the ratios a : b : c :f : g : h are determined by the equations
v=o, □ v=o, □2v=o, □3v=o, n4v=o. . . .
Now, if at the point in question the curvature of U be such that a sixth consecutive
point lies on the conic V, the point is called a sextactic point ; and the condition for this
will be (in terms of the above formulse) □5Y=0. From the six equations Y=0,
□ Y=0, . . D5Y=0, the quantities a , b, c, f, g , h can be linearly eliminated; and the
result will be an equation which, when combined with U = 0, will determine the ratios
x:y:z, the coordinates of the sextactic points of U. But the equation so derived con-
tains (beside other extraneous factors) the indeterminate quantities a, (3, y, to the
degree 15, which consequently remain to be eliminated. Instead therefore of pro-
ceeding as above, I eliminate a, (3, y beforehand, in such a way that (W=0 repre-
senting any one of the series Y=0, □V=0, . . from which a, (3, y have been already
mdccclxv. 4 x
(1)
(2)
(3)
654 ME. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OF A PLANE CURVE.
eliminated) the equations W= 0, □ W = 0, □ 2W = 0 are replaced by
^W==VV=BfW = AW (4)
where ts is a numerical factor, and
a=(b, & c, #, e, ** (5)
To this preliminary transformation the first section of the paper is devoted *. The
second section contains the actual elimination of the constants of the conic, and the
reduction of the resultant to six forms, 3£=0, JH=:0, =j^,=0, %!= 0, JH'=0,
of which % and 01 and 4jW, and ffl! differ respectively only by one and the same
numerical factor, viz. (n— 2)3. All these forms, however, contain extraneous factors,
the determination of which is the object of the remainder of the paper. The third
section is devoted to the establishment of some formulae of reduction, the demonstra-
tions of which are rather too long to be conveniently inserted in what would otherwise
be their more natural place (§ 4). Besides these I have established many others of a
like nature ; but the specimens here given will doubtless suffice to suggest the mode of
proof of the rest to any one desirous of pursuing the subject further. In the fourth
section it is shown that all six forms are divisible by the Hessian of U, and
that %, %! are also divisible by u3, 01, 0\! by v3, and by w3, and that the result
of these divisions is a single expression of the degree Yin— 27.
§ 1. Preliminary Transformation.
The first two equations of the system (3) are, as is well known, equivalent to the
following, viz.
U V w
(6)
where 0 is indeterminate. The third equation, viz. □2V=0, when written in full, is
o= □?a,v+ n^y+ □^zy+x2h2y+^2y+^2Y+2(p^,y+ABAV+^^v). (7)
Noww being the degree of U, we may without difficulty establish the following formulae
given by Cayley (Z. c. p. 381) :
(n—l)u2=—$$z2-\-lJfzy—&y2,
(n—l)v2 = — €x2-j-2(Bxz— Qz2,
(n—l)w2=— %2 +■ 2^yx — B#2,
(n— 1 )vw = — $x2 — <Bxy —^xz-\- Qyz,
{n—l )wu = — $yx + <%2 — ^foyz -f- Y>zx,
(n— 1 )vw= — fzx—<Bzy + $}z2 -f- €xy.
(8)
* In a paper recently published in the ‘ Quarterly Journal of Mathematics,’ vol. vii. p. 114, I have given a
transformation having the same object in view ; but its form is partial and in some sense incomplete, and the
mode of proof less direct and obvious than that given in the text.
MU. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OF A PLANE CTJEVE. 655
whence writing
<E>=(a, b, c,f, g, h)(u, (3, y)2,
we may derive
(n-l)X2 =-^ + 2 to(Zlu-hW+<B>y)-x2<P,
(n-iy
(n— l)v2 = — ^2C-l-2^(#a+Jf/3+Cy)— z2<&,
(n— l)p = — &2#+&z(i§a+3$0 + JV)+^(#a+ Jf/3+Cy) —
(w— 1)j>A =— + Jf/3 + Cy)+^(S a +H/3+#y)—
(w — 1 )Kfb = — h2$ + fy(&a + W + 7 ) + Ml «+Bf3+Jy)—
But, as will be found on calculating the expressions,
(n— l)DX=^(9[a + ^/3 + #y)— x$>, 1
(n— l)DiM-=^0|a+B^+4fy)— y®, 1
(n—l)Uv =&(#a+4f/3-|-Cy)--:s< I>, J
so that
(w-l)2X2 =-^a+2(w-i>nx+^,
(n—lfgJ1 = — §2^3 + 2(w— l)yn(A-\-y2®,
(n— 1)V = — £2C + 2(w— l)z CH -|-z2<I>,
(w— l)2p =— &tf+(n— l){yUv +znp)+yz<i>,
(n—Yfvk =— h20-\-(n— l)(z Wk-\-xnv)-\-zxQ,
(n-l)\gj = —l2$l+(n—l)(x Dp+y □ x)+^. ,
Hence, if m be the degree of V,
(9)
• (10)
(11)
(12)
(^-i)2{A2B2y+iy/b2y+v2B2v+2(pB^2y+^3,Y+^^y)}
= -S2(<3, 33, C, f, 0, l)a, 3„ B JV+2(%-l)(m-l)(n^,V+ D^V+ D^2V),
whence, substituting in (7), and bearing in mind that
(n— 1)S1w+D + ^w)=H^, 1
(n—l)^u+Mv+fw)=B.y, i (13)
(n— l)#M+Jfy + Cw)=H2, j
we have
(»- 1 )! (i +2ar) ( □ *3,v+ □ j»a,v+ O -3.-V) - 8*(a, Ji.i.jr. 6, ® )(3„ 3,, a,)5v= o.
But
□ aV + □ i«aV + □aV=^(wDX+'yD1M/+^(;Dv)
= ,7^1 ( (&u + D + + (Ifou + 33fl + fw)(3 + {<&u + tfv + €w)y }
4x2
656 ME. W. SPOTTSWOODE ON THE SEXTACTIC POINTS OE A PLANE CURVE,
so that (7) finally takes the forms
(a <B, C, Jf, 6, a.)5V- (l+^^)«H=0 .... (14)
or, in the case where V is a conic, and consequently m— 2,
gffl+3BJ+Co+2(4r/+%+»7i)-i^ildH=0; ..... (15)
2 [m i)
and in general making sr=l+ n_ f , (14) takes the form indicated above, viz.
AY— w0H=O, v
°r AZ [ (16)
u v w otH J
§ 2. Elimination of the Constants of the Conic of Five-pointic Contact.
Before proceeding to the application of the formulae (16) to the investigation of the
sextactic points, it will be convenient to premise that if s, t be any two homogeneous
functions of x, y, z, the nature of the operation A is such that
Astf=sA#+tfAs+2(&, 35, C, tf, (B, ||)(b,s, b/, dzs)(dj, df, dzt), . . (17)
and also that
AV=3H, A u=_p, Av=y, A w—r (18)
This being premised, our first object is to establish an equivalent for □3V=0, divested
of the extraneous quantities a, (3 , y. Now, since
X v'dzY-w'dyY)=xDY,
Z(w\Y-udMV)=yU Y,
Xu'dff- vb,V)=snV,
and DS=0, it follows that
i □ ( vbzY - wdyV)=*. □ V +ar □ 2Y,
S □ (wbxY — uby)=(A □ V + y □ 2Y,
&D(wb,V_ »b,V)= *DV+zp2V;
and consequently not only do vbzY — wbyV, vfdxv — ubzY, udyY — vbaY vanish with mV,
but, when this is the case, □ (ybsV— wb^Y), .. vanish with D2V. The same will
obviously be the case if the operation □ be continued ; so that, in general terms, we
may, by operating upon vb^—w'b^Y, . . with the symbol □, 0, 1, 2, . . times, form a
system of equations equivalent to that formed by operating on V with the same symbol
1, 2, 3, . . times. And if we represent any of the three quantities vdzY — vfbyY, . . by W,
the equations W=0, DW=0, •□2W=0 will be equivalent to the system
b«w ayw_a,w aw
u v w ra-jH 5
(19)
MR. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OF A PLANE CURVE. 657
analogous to (16). More generally, if
Ay=u A — xffHd,,
A2=v A— arHdj,,
A3=wA — zzrHc)*,
and if A' stands for any of the three symbols A,, A2, A3, then the equations V=0,
□ V = 0 are equivalent to
-Bjry=-Bwy=-Bsy;
U * V y wz
the equations CPV^O, 0^=0 are equivalent to
-^A'V=-d A'y=-^A'y.
U x v y W z
Similarly, if A'7 stands for any one of the symbols A,, A2, A3, either the same as A' or
not, then D4y=0, [H5V=0 are equivalent to
- d. A" A'V =- A" A'V = - A" A'V,
U x V y w z
and so on indefinitely, for □ 2iV = 0, □2i+iy=0. If the series should terminate with
□ 2iV=0, e. g. D6y=0, then the last equivalent would be A"'A"A'V=0 , where A!"
stands, like A", for any one of the symbols AM A2, A3 indifferently. The form W,
however, presents peculiar advantages for the application of the operations A, as will
be more fully seen in the sequel. And it follows from what has been said above that,
if W retain the same signification as before, we may replace the equations W = 0,
□ W=0 (and consequently the equations Qy=0, D2y=0) by
-d,W=-^W=-B,W,
u x v y w z ’
and in the same way the equations Q2W = 0, □ 3 W = 0 (and consequently □ 3y = 0,
□ 4V=0) by
- A'^W = - A'S,W=- A'B.W,
U x V y w z ’
and so on. I do not, however, propose on the present occasion to pursue the general
theory further.
Returning to the problem of the sextactic points, and forming the equations in W
(19), we have
hx(v B,y- w^y)=^> wB,y)=^B> ^v- wB,v)=^s a(v zzv- w^v) ]
^B>^y-MB,y)=^y(wB,v-MBzv)=:^,(wB,v-w5,y)=^|IA(wb,v-wS,y) .
ldz(u dyV-v *.V)=\b,(u t, JfV)=^« dyV—v dzV) A(« B,V).
(20)
658 ME. W. SPOTTISW OODE ON THE SEXTACTIC POINTS OF A PLANE CUEVE.
2 (n
j =8. Also since BZV, B^V, BZV are
But since W is of the degree n, ^,=1 +
linear in x, y, z, it follows that AB,Y=0, AB^Y = 0, ABzV=0; hence, applying the
formulae (17), (18),
AflB,Y=£d,V+2(a. • JT. • )« Vi, W)(dJdzV, B„B,V, B*V).
But since
9lw' + %)vt + 0u!= 0, + (Bu' = H, Bw' -\- Jfrv1 + Cm' = 0,
it follows that
Similarly,
so that (20) become
A«B,V=2B,V+2HB,B,V.
AwB,y=rB,V+2Hd„B,V,
qdzY—rdpY ■■
3H
:YT<
3H
fBzY — v' B^Y+2^ —2wh)= . .
rBzV— pBzV= =— («/ BZY— w1BzV+2wa— 2ug)= . .
_pByV-jB#V=^(«1BfV-w,d#V+2«^-2m)= . . ,
whence, multiplying by p, q, r respectively, and adding, we have
0 =
p
ux
B*Y
+2
JP
2
w'
a,v
<?
r
if
BZY
b
=
to, BZV=
to>, (22) b
P
u
2a— 6u
=0;
2
V
2 h—6w'
r
w
2 y— to'
u a
v h
w g
(23) takes the form
vr—wq=X , wp—ur= Y, uq—vp=Z ,
w.X+w'Y+t/ Z=P
w'X+^j Y+w' Z=Q
«/X-f«i' Y-j-w1Z=R, ]
2(aX+AY+yZ)-4P=0;
(21)
(22)
(23)
(24)
or finally substituting 2 (ax-\-hy -\-gz)=6u, and forming similar equations in Q and R,
we have the system
a(uK—x P ) + h(u Y — yP ) +g(uZ — zP ) = 0
k(vX— xQ) -j- b(v Y — y Q) -f- g(v Z — zQ) = 0
g(wX—x R) +f(wY — yR) + c(wZ — sR) = 0,
(25)
ME. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OE A PLANE CTJEVE. 659
which may be regarded as the three forms by any one of which □3Y=0 may be
replaced. Before proceeding farther, it will be convenient to notice that the quanti-
ties uX— #P, . . are capable of being transformed in a manner which will be useful
hereafter, as follows : —
TlX = Xuxx + (ww' — vv')jjx -\-(v'q— w'r)ux
=Xu1x + ( ww ' — vv’)( 3n—2ll—qg—rz)—(v'q— w'r)(vy — wz)
= Xfax + w'y + v'z) + 3 (n — 2)H (ww' — vv')
=(n—l)uX-\-3(n—2)~H.(ww'—vv'),
i. e.
— uX+x¥=(n— 2){uX— 3H(W — ww')} 1
-wY+^P=(w-2){mY-3H(ww1-W )} l (26)
— vJL -\-z¥=(n— 2){uZ — ■3H(W — vux )}. J
Returning to (25), and taking any one of the three as W, we shall have for □3V=0,
□ 4V=0, □5V=0,
a~bJ(uX Kbx(uY —yF)-\-gdx(uZ — ^P) — 02u =0 1
ddy(uX-xF)-\-liby(uY—yF)-{-gby(uZ—zV) — 02v =0 |
adz(uX—xV)-\-Jidz(uY—yV)-\-g'bs:(uZ—zF)— 02w =0
a A (uX — x~P) + A A(wY — yP) + gA(uZ-zT) - ^11= 0 ; ,
and similar groups may be formed from the other two equations of (25). Now as (27)
contain only three out of the six constants a, . . fx . . , and the single indeterminate A,, they
are sufficient for the elimination in view, and give for the equation whereby the sextactic
points are to be determined,
B,(mX-^P)
B/«*Y-yP)
B>Z-zP) a,
d>X-tfP)
B/*Y-yP)
B/wZ— zP) u
=0, j
i
B>X-#P)
B/uY-yP)
c)z(uZ—zP) w
r
J>
1
%
A(WY-yP)
A(uZ-zF) „2H
i
which, in virtue of (26), may also be written in the form
(^{wX— 3H)w/— vow')} 'bx{uY—‘YSi(wul—uv')} B*{>Z— 3H(W— vux)}
dy{wX— 3H)W— ww')} 'by{uY—oH.(wul—uv')} ~by{uZ— 3H(W— vuj}
BJ.{wX— 3PI)W— ww’)} Bz{wY— 3H(«nq — uv ')-} ~bz{uZ— 3H(W— vux)}
A{wX— 3H)W— ww1)} A{wY— 3H(mq— uv')} A{uZ— 3H(W— vux)}
=0,
v
w
G3r2H
with similar expressions in v, Q ; w, R. Calling (28) and (29) %, %' respectively,' we
may designate the entire group of six forms, three of the form (28), and three of the
form (29) by
1=0, ifl=0, #=0, 31' =0, iH'=0, $,=0.
(30)
660 ME. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OF A PLANE CUEYE.
And as %, differ only in respect of a numerical factor, any other factor that can be
predicated of % may he affirmed of %!, and vice versd ; and similarly for the other pairs
§ 3. Formula? of Reduction.
The degree of the expressions (28) or (29) is 18w— 36; it remains to show that existence
of certain extraneous factors, which when divided out will reduce the degree to 12 n — 27,
and at the same time render the three forms identical. But before entering upon this,
it will be convenient to premise the following formulae, the first group of which are easily
verified.
y7j —zY =3(w— 2)Hm 1
zX—x Z = 3(n— 2)Hy
xY-yX=3(n-2)Hw
ybxZ — zB^Y — (3n—7)up—(n—l)wp -\-3{n—2)FLux
ydyTi —zdyY =(3n—7)uq ~{n — 1 )vp -\-3{n— 2)Hw'
y~bzZ — zdeY =(3n—7)ur -(w-l)wp+3(rc-2)IR/
zbxX-x'bxZ =(3n—7)v]) -(n-l)uq + 3(n-2)Hw' ^
zbyX.—x'byZ =(3n—7)vq — ( n — 1 )vq +3 (n — 2)11?;,
zB2X— x'dJZ =(3n—7)vr —(n—l)wq-\-3(n—2)11u!
x~b^Y —ybzX=(3n—7),wp—{n—\)ur -\-3{n— 2)HV
x~by Y —ydfL =(3n-7)wq—(n—l)vr-\-3(n— 2 )Hu'
#B2Y —ydzX=(3n—7)wr — (n—l)wr + 3(n—2)Hw,. >
And writing
-P1=^>I+Yr'+Z2' |
-Q-Xr' +Yq1 + Zf (32)
— R^X#' + Yf-^-Zr^ j
then also
Y^Z-Zd,Y=-(i?P+wP1) ZB.X-XB^-feP+flPJ XB2Y — YB ^X = — (rP + wP, ) 1
YByZ-ZbyY=-(i?Q-fwQ1) ZB.X-XB^-^Q+uQ,) XB^-YB^-^Q+wQ,) 1(38)
YB2Z-ZB2Y=-(^R+wR,) Zh2X— XBzZ= — (g'R+'yRj) XB2Y-YB2X=-(rR+wR1)J
Moreover, writing with Professor Cayley,
(& b, c, jr, 0, i)(B„ b„ hz)2H=o
3$, C, f, 0, fc)(B„ B„ B.ft, B yQjj= . . , BsQy= . .
BA=(B,a B,£, B2c, Bjf, dx0, BJ>)(B„ B„ dJH, B,Qh= • •
ME. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OE A PLANE CIIEYE. 661
and noticing that
X-dj-Ou-}-!! ByQu-{-/3zQu — Jac. (U, H, Qu),
. . . (35)
and that
AX= vdzQv—wds O0 1
AY -wdx£lv- dd., OrJ 1
AZ = wd^Qu— wb^Ou, |
. . . (36)
then we have
YAZ -Z AY —u Jac. (U, H, tjAZ -z AY=(5w-12)Qm 1
Z AX— XAZ s=v Jac. (U, H, Qn) zAX-xAZ =(5n-l2)Qv i. . (37)
XAY— YAX=w Jac. (U, H, QD) ®AY— yAX=(5»-12)Qw.' I
Again, if 33', C', 4F, 0', be the same quantities with respect to H that
3, 33, C, jf, 0, are with respect to U, i. e. if Q!=qlrl— p'2, . . jfl=q'r'—plp', . . ,
and if
©=($', 33', C', f, 0', H')(w> wf ] _ ^
^=(& 33, C, f, 0, H)(ih q , r)2,
then
Uy
c^Z=Jac. ( u , Yr, Z,)=w,
if p — ux r + wpx — uqf
w'
^Z w'
dp—w'r-\-wif —up1
if
dzY
dsZ «/
Wy p—v' r-\-wq' —urx
=Hp2
— Hp2 — Qpu + (%{p j + $|r' + 0#' )pu
— (!?*' +33^1 +Jfp')pw
+ (11^1+33/ + Jfy' )pv
+(<®Pi+$rr' +€q')wp
+(0^i+ + CV )ww
-(02' +4^ +Cr» )pt*
+(91'mi +Hfw'+0V)w2
+ (H'^i+33V+ f'v')uv
+(Hih + 33/ +jf2/)jw
+(0Pi +4^ 4-C^'
+(&'%, +^V + 0V)m2
+(H'wi+35 V -j-ffi'v'juv
+ (0'w i + 4f V + C )mt?
Similarly,
Jac. (w, Z, X)=wt ■w/p+wr' — w'r—v1 q-\-vq’ — wr'
■y' w' ^ — dp + up' —vq' dr — Wjy-f- Wj — wp1
4 Y
MDCCCLXV.
662 ME. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OF A PLANE CUEVE.
=Hjpff
3^ 7
= — Op — (0/ + + <&p’)up — H pq — Qpv + $t>d,0D + %|
— (<%' + Jfjp' + Cr, )vp — 0fyr' +36#, +$p')uq
\udy"tyv
+ (W +ffql +€/ )wp
—(<3r' +fqx +Cy )ur
-(W +33$'i +tfp')uq
+ (9'Mj +^'w'+(B'v')uv
+ (#i>i +4^ +C^ )w
+(fe+^' +4^ >2
+ (3^'te, +2SV + fv'y
+ (&ut +4fV +CV)w
Hence •
-(<gr' +#^+Cp>r
+(9^
+{W +
+(#/ +4f2i+Cp')wp
+($P1
+(?%L+23/ +4^')^
+(%i+ JV +C£')n>
Jac. («, Y, Z)=%^Hp! -(Qi)-ia,©u)M
Jac. («, Z, X)=i£=f> Hp?-(Qp-i3.,0o>+J«9^„-iM9,^u
Jac. (w, X, Y)=4^’i_12) Hpi — (Qp — ja,0„)w+iw3t'I,n—
4 (72 — 2)
Jac. («, Y, H#p— (Gj— J9y0u)«+^B,^u—
Jac.(t>, Z,X)=i^Hf-(O2-i3,0„)» l . (39)
Jac. (v, X, Y )=~~ H(?r— (O^—
4(n~2) 1
Jac. (tv, Y, Z)=-^rr; Hrp-(Qr-pz0u>+i^^u-iw^u
Jac. (w, Z, X)=^rHi-2-(Q,— p,0„)*+i«3,^„-iw3,^o
Jac. (w, X , Y)=^|^Hr! -(Qr-|a,0,)w.
Again,
•r Jac. 0, Y, Z)+?/ Jac. (v, Y, Z)+z Jac. (w, Y, Z)=(»— 1) Jac. (U, Y, 7) ;
whence, bearing in mind that
^»+?3,^u+*3.^o=2(3»- 7)¥„,
^*0o+y3»0tI+23,©„=2(K-l)0u,
ME. W. SPOTTISW OODE ON THE SEXTACTIC POINTS OF A PLANE CTTEVE. 663
because in the differentiations £5, . . . SI', . . are supposed constant, it follows that
Jac. (U, Y, ]
Again,
12 (n
Jac. (U,
3 n — 7
3(n — i
Jac. (U,
X, Y)=^
Mi d*Y
~dxZ=ux
w' ByY
a,z «/
i/ d2Y
s2z
(40)
=^2H —(%rr +43?! +Jfp')wp +(<3'u1+$r,w'+€lv')wu
+(®p, +#/ +C?')wp+($'w1 +?I)V +<§V)w2
— ((Bq1 +fj>'+^rl)uj) +(W?L+4$V +4fW)w>
+(li>i+43r' +#?>?>
. . JT, . .)(**, v, w){u„ w', v')u.
Whence
Jac. (u, Y, Z)=^£^ Hp2 -O Mp + (g', . . jf', . .)(««, w)(%„ w', v')u
Jac. (m, Z, X)=^^ Hp?-1%+(ST, . . 4f', . .)(«, v , w)(«/, w>
Jac. (m, X, Y)=^^ Hpr-Qwr +(3', . . jf', . .)(«, «, w)(®*, < w>.
(41)
A similar process of reduction conducts to the relation
Jac. (X, Y, Z)=— (A, . . f, . .)(p, q, r)(p„ r', ?')X— (£', . . f:. . .)(u, v, w)(u„ w\ t/)X
— (3, • • S, • -)(JP» A* r)(^ )Y— ($', . . JT, . .)(w, V, w)(w\ w')Y
—(SI, . . JT, . •)(?> ^)(?',i>', )Z— (S', . . jT, . .)(«*, «, w)(+ w,)z
= — Jac. (U, H, ^u)— Jac. (U, H, ©„).
Whence also
Jac. (wX, %Y, u7i)=v? Jac. (X, Y, Z)+w2{X Jac. (w, Y, Z)+Y Jac. (X, u, Z)+Z Jac. (X, Y, u)\
= -w3Jac.(U, H, ^D).
4 y 2
664 MB. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OF A PLANE CURVE.
$4.
The resultant equation which, when combined with that of the original curve, will
determine the sextactic points, was exhibited in § 2 under six different forms, there
designated by
1=0, iH=0, #=0, £'=0, iW=0, #=0.
Now since % and %!, i'H and XW, iX and -ffij respectively differ only by the numerical
factor (n— 2)3, we shall, in seeking to discover the extraneous factors, employ either
S., . . or ■%!, . . as most convenient for the purpose. And in the first place it will be
shown that H is a factor of all these expressions. Putting H=0, %! becomes
oxuX bxuY bxuZ u — 0 ;
byuY byuZ • v ....... (43)
bzuX bzuY bzuZ w
A uX AuY AuZ gt2H
also
AwX=j)X+mAX+2HB#X I
AmY=jpY+wAY+2HB,Y (44)
AuZ =pZ -\-uAZ +2HdxZ ; |
so that the above equation, written in full, is
uYX +wb^X UjY -f-wdxY w,Z -\-ubxZ u
w'X +wb?X w'Y +mc^Y w'Z -f- ubyZ v
v’X+ubzX v'Y +ubzY . v'Z+nbzZ iv
p X +uAX+2HbxX p Y +mAY+2HBxY p Z +uAZ + 2llbxZ ar2H.
Although this expression contains terms explicitly multiplied by H, which might on
the present supposition be omitted, it will still perhaps be worth while to develope it
completely. Expanding in the usual way, it becomes
u*X ux <3,Y bJZ u +w2Y ul bJZ bxX u +u2 Z u, bxX bxY u +u3 bxX bxY bxZ u
V) ' b,Y byZ V W' byZ ^ ,X V ^ b,X V d,X b y Y V
v' bzY bzZ w v' bzZ bzX w v' bzX bzY w bzX bzY bzZ w
p AY AZ *t2H p AZ AX st2H p AX AY sr2Ii AX AY AZ
+H u^X-\-ub^X MjY+wB^Y u{L-\-iib^L u
w'X+wc^X w’Y+ubyY w'Z-\-ubyZ v
P X + wbzX v'Y-\-ubzY v'Z-\-ubzZ w
2 b,X 2bxY ' 2bxZ sr2.
ME. W. SPOTTIS WOODE ON THE SEXTACTIC POINTS OF A PLANE CUEVE. 665
In this the coefficient of — p
=±{d„X Zb,Y-Yd,Z u +B,Y X^Z-Z^X u +d„Z Y^X-X^Y u)
^X Z^Y-Y^Z v d,Y Xd,Z-Zd,X v ~byZ Y^X-Xd.Y v
d,X Zb.Y—Y'dJZ w b,Y X^Z-Z^X w ~dzZ Yd*X-X^Y w
=±{p'bxK+qdieY+rdxZ P u +udxK+v'bxY+w'd;Z P, u}= P, P u
pbyK+qbyY +rdyZ Q v ubyX-\-vb^-\-wbyZ Q, v Qt Q v
jpdzX-j-^dzY-j-rdzZ R w ub^X-\-vbzY -\-wbzZ R, w R, R w.
Now
« «. P, = ^I{2(»P,+SQ,+4rEl)-y(1gP,+jrQ,+CE1)}
v w' Q,
w t/ R,
« »' P.=^{*(@P,+4fQ,+CE1)-z(aP,+®Q,+®R,)}
V v , Q,
w v! R,
« »' P. = ~ i{y(aP,+®Q1+©R1)-*(®PI+33Q1+JrK,)}
w id Q,
w ro, R, ;
so that multiplying these equations by X, Y, Z respectively, and adding,
» P P, =^T{(aP,+BQ, + ©E,)(yZ-2Y)
» QQi +(lP1+SQ,+JrE1)(zX-xZ)
w R R, +(eP,+^Q,+CK,X«Y-yX)}
= 3tx2> H { a»+®» + ®ro)P, + ( J) « +33» + Jfw)Q, + (i6k+ jfo + C»)E, }
= f^H’fp-*+9'?+E-*)
= ~ vi(i"r ^(Xp+Yg+Zr)
(45)
= 0.
666 MR. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OE A PLANE CURVE.
Hence the whole expression
=zz2{zz, zz YB,Z-ZB,Y B^+zz, zz ZB.X-XB.Z B^Y+zz, zz XB.Y-Y B,X B,Z}
w' v YB,Z-ZB,Y B,X w' v ZB.X-XB.Z ByY zy' v XB,Y-YB,,X B,Z
V1 w YBaZ-ZB*Y B*X v' w ZB2X-XB2Z B*Y v' w XB, Y-YB*X B*Z
. W.2H YAZ-ZAY AX . st2H ZAX-XAZ AY . sr2H XAY-YAX AZ
-fzz3B;X B*Y B,Z u
B,X B^Y B,Z v*
B2X B2Y B2Z zy
AX AY AZ tir2H ;
or in virtue of (33),
— ZZ2{ZZ, ZZ — (^P+ZzP,)
B^X+zz, zz
-(jP+yPJ
B^Y+zz, zz
— (rP+zyPj)
3.Z}
zy' y — (pQ+zzQ,)
ByX zy' v
— (ffQ+yQi)
B,Y zy' y
— (rQ+zyQ,)
3,Z
y' zy — (^zR+zzR,)
B2X y' zy
— (^R+yR,)
B2Y y' zy
— (rR+zyR,)
3,Z
w2H zz Jac.(U, H,Ou) AX . et2Hz; Jac.(U,H, Oy) AY . ®2Hro Jac. (U, H, 00) AZ
+zz3B.,X B*Y B,Z zz
B^X B^Y ByZ v
B,X B2Y B2Z zy
AX AY AZ *t2H
=2zz2ot2H zzj Pj P+zz2Jac. (U, H, Q^zz, zz P +zz2 Jac. (U, H, Ou) zz, zz P+zz3B*X B2Y B,Z zz
zy' Q, Q zy' v Q zy' v Q B^X B^Y B^Z z;
z;' Ej R y' zy R y' w R B,X B2Y B2Z w
AX AY AZ kt2H.
But
*1 P. P=Z(lP1+BQI+4TPi)-Y((gP1+4fQ1+CB1)
zy' Q, Q
y' R, R
=zz(a 33 C jf # i?)0 2 r)(P1Q1R1)-^(9[ 33 € f 0 Mu v ^XP.Q.R,)
=«(a 33 c # e Mp 2 rXPABi),
(a 33 C jr <§ £)(«. y, «)P1Q1RI)= J^TH(P1af+Q1y+B1*)=0,
(a 33 c jr - (a . .)(? ? ^ »•' <z')x
+(a..)(p^ ^ ^y)Y
+(a ..)(!» 2 rXa'jp' rjz
= Jac. (U, H, N^).
also
ME. W. SPOTTISWOODE ON THE SEXTACTIC POINTS OF A PLANE CURVE. 667
Hence the whole expression above written
= 2w3 jsr2 Jac. (U, H, ^u)+ H Jac. (U, H, Q^H+w3
^X.., •
But
and
b*x
B,Y
B,Z u = - H2 Jac. (U, H, Q*),
B,X
B,Y
B,Z «
B,X
BZY
BzZ to
AX
AY
AZ .
B*X
B,Y
BzZ = - Jac. (U, H, ^)- Jac. (U, H, 00;
B,X
B,Y
B,Z
BZX
BZY
b2z
Hence, finally, the whole expression
=v? H^Jac. (U, H, yn)+ (^Ef - ‘(i-7^8) H Jac’ (U- H’ Q)-®.Jac.(U, H, 0„)}
(U, H, ¥„)— Jac. (U. H, 0„)) - H Jac. (U, H, Q„)j.
which is therefore divisible by H u3. Consequently H is a factor of all the expressions
H, . . %! . ., which was to be proved.
Although not absolutely necessary to our argument, it is perhaps worth while to show,
as may readily be done, that % is divisible by u. Omitting the terms explicitly multi-
plied by u in the first three columns, the equation becomes
WjX— B^P WjY—d^P w,Z— BirzP
w'X-B^P w'Y-B^P w'Z-B,zP
t/X-B^P t/Y-B^P t/Z-BzzP
p X-AtfP+2HB;X p Y-A?/P+2HBZY p Z-AzP+2HBzZ vrJEL
In this the coefficient of w2H,
~P — (Yz — Zy)
w'B, P
+ V(Zx-Xz)
t/B,P
H-P(Xy-Y^) 1 MjBJ*
i/B,P
w,BzP
1 w'B^P 1
+P(M1X+wYP+«,Z)-Pa(arB#P+yByP+»BltP)-P8,
which, writing
=0. )
(47)
= -(w-2)(3HK-}-5P2)P.
K —u ux B*P
v to' ByP
w v' B„P
668 MR, W. SPOTTISWOODE ON THE SEXTACTIC POINTS OE A PLANE CURVE.
Similarly, it will be found that the coefficients of
(^X— A#P+2HbrX)
(pY — AyP + 2HB ,Y)
(pZ -AsP+2Hb,Z)
are
-(w-2)(3HK+5P>,
-(w-2)(3HK+5P>,
_(w_2)(3HK+5P>
respectively ; and consequently the whole expression
= — (w — 2)(3HK-f-5P2) { (^>X— A#P -f 2Hb^X)%
+Q>Y-AyP+2Hd#Y)t>
+(_pZ - As P + 2Hd,Z )w + ^2HP }
= -(?*— 2)(3HK + 5P2){—2HP—2(a. .)(«, % w)(b,P, byP, B,P)-f-«raHP}
= _(„_2)(3HK+5P){-2-^=S+-!}HP.
2)
But ro-2=l-f- — * so that above expression
=(rc-2)(3HK + P2)HP.
Now
-(w-2)(3HK+P2)=w
u
p
a,p byp
v w n\J
w' v' (n—l)(u—u)
q r , ‘6{n— 2)H
5(w— 2)P.
u w xu -\-yv -\-zw
w' v' xut -\-yvo' -\-zv'
p q r xp -\-yq -\-zr
b,P ByP BJP a?a.P+yBrP+*a,P
= — (n — 1 )u u p b^P
v q dyP
w r d,P :
—u
u
i-l>
• (48)
so that the whole expression is divisible by u. Similarly, it might be shown that M,
or M' is divisible by v, and N or N' by w.
It follows from what has gone before that %, are all divisible by
H, that %, are divisible by u, iPT by v, by w, and consequently dividing
ME. W. SPOTTIS W OODE ON THE SEXTACTIC POINTS OE A PLANE CURVE. 669
out those factors, the three expressions %, JB, ^ are of the form
Am2 +B,w +C1=0,|
Kv2 +B2v + C2=0,1 (49)
Aw2-fiB3w+C3=0,j
in which the coefficients of u2, v2, w2 are the same, viz. the expressions given in (46).
From these equations it follows that
BjW + Cj B2W + C2 BgW -f Cg
~77 7 77 • { }
But as u, v, w do not in general vanish simultaneously, these relations can hold good
only in virtue of B, being divisible by ux and C, by u2 ; B2 by v, and C2 by v2 ; B3 by w and
C3 by w2. Whence, finally, % is divisible by H u3, JB by Hw3, ^ by Hw3; and yhe
degree of the equation is reduced to
(18»-36)-3(»-2)-3(»-l)=12»-27.
Also, since the ratios (B^+Cj) : u2, (B2-y+C2) : v2, (B3w+C3) : w2 are in virtue of (50)
equal (say =B), it follows that JB, %!, JB', all lead to the same result,
viz. A+B=0, which it was our object to prove.
4 z
MDCCCLXV.
’
[ 671 ]
XV. On the Marsupial Pouches , Mammary Glands , and Mammary Foetus of the
Echidna Hystrix. By Professor Owen, F.B.S., &c.
Beceived February 18, — Bead March 2, 1865.
In the year 1834* it was known that the ovum of the Ornithorhynchus paradoxus left the
ovarium with a spherical yelk or vitellus about If' (lines) in diameter, and that, having
reached the uterine portion of the oviduct, it had acquired a smooth subtransparent
chorion or outer tunic separated from the proper membrana vitelli by a clear fluid.
Such ova, usually two in number, had been detected in females killed in the month of
October, in the left uterus, of sizes ranging from to 3^"' (lines) in diameter, without
any sign of organization of the chorion, or of preparation for placental adhesion on the
uterine wall.
The increase of size in the uterine over the ripe ovarian ovum was due to increase of
fluid between the chorion and vitelline tunics.
This fluid, homologous with the albumen of the egg of oviparous vertebrates, did not
coagulate in alcohol, and the only change presented by the vitellus of the largest
observed ovum was a separation from the “ food-yelk ” of a “ germ-yelk ” in the form of
a stratum of very minute granules, adhering to part of the membrana vitelli. There
was no trace of decidua in such impregnated uteri ; the smooth chorion was firmer than
that of uterine ova of Bodentia ; whence, and for other reasons given in the paper above
cited, it was inferred “ that the Monotremata are essentially ovo-viviparous.”
In the same year (1834) I received a young of the Ornithorhynchus paradoxus from a
nest of that animal, discovered by Lieut, the Hon. Lauderdale Maule in the banks of the
“ Fish Fiver,” Australia. This progeny, Plate XLI. fig. 5, measured in a straight line
about 2 inches (other admeasurements will be subsequently given) ; it was naked, blind,
with short, broad, flexible, and softly labiate mandibles ; the tongue was proportionally
large, and reached to near the end of the mandibles ; the mouth was not round, as in the
mammary foetus of marsupials, but in the form of a wide transverse slit ; a pair of small
nostrils («) opened upon the upper mandible, and between them was a small prominence
( e ), resembling the knob on the beak of the newly-hatched chick, but softer, and lacking
the cuticle which had been torn off. There was no trace of navel or umbilical cicatrix f.
The mouth of this young Platypus, or Ornithorhynchus , was adapted to be applied to the
flat teatless areola upon which the numerous lactiferous ducts of the parent opened J,
* “ On the Ova of the Ornithorhynchus paradoxus ,” Philosophical Transactions, vol. cxxiv. p. 555.
t “ On the Young of the Ornithorhynchus paradoxus,” Zoological Transactions, vol. i. p. 221.
X “ On the Mammary Glands of the Ornithorhynchus paradoxus,” Philosophical Transactions, vol. cxxli. p. 517.
MDCCCLXV. 5 A
672 PROFESSOR OWEN ON THE MARSUPIAL POUCHES, MAMMARY GLANDS,
and it was inferred that thus it received the lacteal nourishment with the aid of the com-
pressor muscle of the large mammary gland.
The principal points in the generation of the Monotremata which remained to be
determined by actual observation were —
1st. The manner of copulation.
2nd. The period of gestation.
3rd. The nature and succession of the temporary structures developed for the
support of the foetus during gestation.
4th. The exact size, condition, and powers of the young at the time of birth.
5th. The period during which the young requires the lacteal nourishment.
6th. The age at which the animal attains its full size.
“ Notes ” of these desired facts, with indications of the times and places most likely to
supply them, have been sent by me far and wide, through Australia and Tasmania ; and
after the lapse of thirty years, I have been favoured with materials for making some
further advance in this interesting physiological problem — a small one, it is true, but
such as seemed to me worthy of being submitted to the Society as an addition to former
records on the subject contained in the Philosophical Transactions.
For these materials I am indebted to my friend the accomplished botanist, Dr. Fer-
dinand Mueller, F.R.S., of Melbourne, Australia. They consist of a female Echidna
( Ornithorhynchus Hystrix of Home, Echidna Hystrix of Cuvier, the “Porcupine Ant-
eater” of the colonists) and her young one, or one of her young, which was observed,
as the captor supposed, suspended to a nipple when the animal was first secured. After
five days’ confinement the young was found detached and dead, was put into a bottle of
spirits, and, with the mother still living, was transmitted from “Colac Forest,” Victoria,
the place of capture, to Melbourne. Here the female Echidna was examined by
Dr. Mueller and Dr. Rudall of Melbourne, and was then transmitted to me, together
with the young animal, and the following “ Notes” of their dissection.
“ Brief Notes on the Generative Apparatus of the female Echidna.
“ The animal being excessively difficult to handle it was immersed in cold water, and
by these means and the additional use of hydrocyanic acid its life was extinguished. A
longitudinal incision was made from the orifice of the cloaca upwards to the length of
about 5 inches. Five larger and some smaller ovules were found arranged in a grape-
like manner, the largest measuring from l1" to If' ” [lines] “ in diameter. Fine vessels
expanded reticularly over the surface of the ovules. We vainly endeavoured to trace an
opening at the ovarian end of the oviduct. Oviduct about 2" ” [inches] “ long ; its upper
extremity expanded and attached to the ovarium. As a probable sign of recent functional
activity, were noted a number of large distended veins lying between the layers of the peri-
toneum. Numerous oval mesenteric glands were seen. ‘ Meatus urinarius ’ lying in the
inferior wall of the cloaca about f from the orifice. The ureter terminates in a con-
spicuous conical protuberance from 3'" to 4'" long. No other exit for the urine from the
AND MAMMAET FCETUS OF THE ECHIDNA HYSTRIX.
673
bladder being found but the point into which this conical protuberance fits, the ingress
and egress of the urine, as far as we believe, takes place at the same aperture. In close
proximity, and lateral to it, the oviducts terminate by slit-like openings. The mucous
membrane of the thick walls of the oviducts are, at least in the lower portion, longitudi-
nally folded. The oviducts are suddenly narrowed for about from the lower orifice,
offering some resistance to the passage of an ordinary sized probe.
“The upper portion of the oviduct seems of a structure capable of considerable ex-
pansion during gestation. The upper portion was dilated and thin, and a probe could be
passed to near one of the ova. The lower portion of the rectum is so large and so capable
of distension as to admit of the periodical inclusion of the young animal, in case its great
size should possibly be provided for that purpose, as it is a receptacle large enough for a
young animal twice the size of that found now with the mother. The foetal young may
possibly have been extruded prematurely after the capture of the animal. We found
no cicatrix of an umbilical cord on the abdomen of the young animal. ^
“A rough sketch of the young as seen by us is appended (fig. 1). It was
of a pale colour* ; no apertures for the eyes were yet visible in the skin, nor
were any tegumentary appendages formed. The finder contends that he saw
the young external to the mother and alive. We purposely abstained from
the internal examination of the young one, so as not to mutilate the only
specimen available. The four mammary glands at this time are apparently
quite rudimentary ; they are destitute of nipples, as are those of the Orni-
thorhynchus. N or was there the least appearance of milk in these glands.
From the imperfect means of judging we had, we incline to the opinion that Young Echidna,
the Echidna cannot be oviparous.
(Signed) “ James T. Rudall.
“ Feed. Mueller.”
“ Melbourne, August 25, 1864.”
On receiving the specimens I proceeded to examine the female Echidna, and was gra-
tified by finding unmistakeable evidences of marsupial structure. On each side of the
abdominal integument, about two inches in advance of the cloaca, and about three inches
and a half from the base of the tail, there was a semilunar pouch, with an aperture lon-
gitudinal and directed towards the median line, half an inch in depth and two-thirds of
an inch in length of aperture, forming a symmetrical pair with their orifices opposite
each other (Plate XXXIX. a, b).
These pouches were not at first apparent, being concealed by the hair which covers
the under part of the body. It was in turning over this hair in quest of any rudiment of
nipple, that I came, to my surprise, upon one of the pouches. The first doubt was
whether it might have been produced by an accidental pressure of the end of a thumb
or finger in the previous dissection of the animal, which depression had afterwards got
hardened in the spirit ; and to solve that doubt I proceeded to examine the opposite half
* “ Said originally to be bright red. — F. M.”
5 A 2
674 PROFESSOR OWEN ON THE MARSUPIAL POUCHES, MAMMARY GLANDS,
of the ventral integument, when a pouch or inverted fold of precisely similar shape,
depth, and dimensions appeared, but with the opening turned the opposite way ; the
folds were closer and less conspicuous on that side, the cavity of the pouch being flatter
(see section, Plate XL. fig. 3), whence I inferred that the more open pouch (ib. section,
fig. 2, c) had been the seat or nest of the very small and probably recently-born animal,
whose position there, as in the figure, Plate XXXIX. a , had naturally led the original
captor of the Echidna to conclude that it was hanging by a nipple.
No such projection, however, presented itself in any part of the inner surface of either
pouch ; but at the fundus of each was an “ areola ” or elliptic surface, about four lines
in diameter (Plate XL. fig. 4), on which, with the pocket lens, could be discerned the
orifices of about fifty ducts of a gland. The canals or roots of fine scattered hairs and
several minute white papillae (ib. fig. 5,^?, p, magn.), about one or two lines apart, on
which opened sebaceous follicles, were all the appearances characterizing the otherwise
smooth and even surface of these inflexions of the abdominal integument.
The contrast which this pouch presents with that of a true marsupial quadruped con-
taining the mammary foetus* is great; for even in the uniparous species, e. g., the larger
Kangaroos, two, if not four, long slender nipples are conspicuous, to one of which the
foetus hangs, closely embracing the pendulous extremity of the nipple by its small, round,
terminal, tubular mouth.
My next step was to test the statement in reference to the number and condition of
the mammary glands.
I found, as in a former dissection of a younger unimpregnated female Echidnaf , that
these glands were two in number, forming, like the pouches, a symmetrical pair (Plate
XL. fig. 1). Each gland (a, a!) was of a flattened, subelliptic form ; the left (a) being
1 inch 10| lines, the right (a!) 1 inch 8^ lines in long diameter, the left 1 inch 5 lines,
the right 1 inch 3 lines in short diameter across the middle, and both glands about 5
lines in thickness at the middle part (figs. 2, 3). Each gland consists of about 100 long,
narrow, flattened lobes, obtusely rounded at their free ends, and beginning, at about half-
way towards the opposite side, to contract gradually to the duct which penetrates the
corium (Plate XL. figs. 2 & 3, 5), to terminate on the mammary areola (ib. c ) at the fun-
dus of the pouch. From the small size of the areola compared with that of the gland,
the lobules have a convergent arrangement thereto, each terminating in its own duct,
without blending with the substance of a contiguous lobe ; and, as a general rule, with-
out anastomosis of contiguous ducts to form a common canal. Each gland is enclosed
in a loose capsule of cellular tissue (fig. 1, e, e) and lies between a thick “ panniculus car-
nosus” (figs. 1, 2, 3, d, d1), adherent to the abdominal integument (f,f) and the “ obli-
quus externus abdominis ” muscle, on a plane exterior or “ lateral ” to the pouch. The
glands had not been exposed or disturbed by any dissection in the preliminary examina-
* For the signification of this term see “On the Generation of the Marsupial Animals,” Philosophical Trans-
actions, vol. cxxiv. p. 333.
f “On the Mammary Glands of the Ornithorhynchus ,” Phil. Trans., tom. cit. p. 537, PI. XYII. figs. 2 & 3.
AND MAMMARY FCETUS OR THE ECHIDNA HYSTRIX.
675
tion of the animal at Melbourne. The lobules of each gland converge toward the mesial
line, in their course to terminate in the fundus of the pouch. Each lobe is a solid
parenchymatous body ; the duct is more directly continued from a canal which may be
traced about halfway toward the fundus of the lobule; the canal gives otf numerous
short branches from its circumference, which subdivide and terminate in clusters of sub-
spherical “ acini ” or secerning cellules. The structure is on the same general plan as
that of the mammary glands in higher mammals, but the cellules are proportionally
larger ; it closely resembles the structure of the lobes of the same glands hi the Orni-
thorhynchus, and in neither Monotreme can the elongated lobes be properly termed
“pyriform cgecal pouches.”
The converging termination of the lacteal ducts at the fundus of a pouch, or inverted
fold of the skin, resembles the disposition of those parts in the Cetacea ; save that here
the ducts terminate on a prominence or nipple projecting from the fundus of the pouch
into its cavity ; whilst in the Echidna they terminate in the smooth and even concave
surface of the fundus of the pouch.
Calling to mind Mi'. Morgan’s observation of the concealed nipple in an inverted sac
of the tegument at the fundus of the pouch in the young or non-breeding Kangaroo,
where, instead of a nipple, there was seen only “ a minute circular aperture, resembling
in appearance the mouth of a follicle” *, I made sections of both the marsupial or
mammary pouches and glands (Plate XL. figs. 2 & 3) satisfactorily demonstrating that no
inverted or concealed nipple or any rudiment or beginning of such existed ; and, indeed,
had any such arrangement like that of the Kangaroo been characteristic of the mam-
mary organization of the Echidna, the glands being functionally active and well deve-
loped in the female dissected, such nipple would have been everted, and would have
served, as the first observer of the young animal in the pouch believed, to have attached
and suspended it to the parent.
But it is evident that the young simply nestles itself within the marsupial fossa,
clinging, it may be, by its precocious claws to the skin or hairs of that part, and im-
bibing by its broad, slit-shaped mouth the nutritious secretion as it is pressed by the
muscles acting upon the gland from the areolar outlets of the ducts.
The skin of the abdomen, where it begins to be inverted, loses thickness, and at the
fundus of the pouch (ib. fig. 1, b, fig. 3, c) is only half as thick as where it overspreads
the abdomen (ib. fig. 1 ,f). This modification, and the relation of the pouches to the
mammary glands, prove the structures shown in Plate XXXIX. a, b , and Plate XL.
figs. 2 & 3, c, to be natural, not accidental.
The pair of lateral folds or clefts into the bottom of which the lacteal ducts open, in
the Echidna are homologous with those similarly related to the mammary glands in
Cetaceans, and also to the more developed folds or pouches in Marsupials. In Ceta-
ceans the pair of tegumentary clefts have exclusive functional relations to the mam-
mary organ ; in Marsupials the superadded office of receiving and protecting the young
* “ A Description of the Mammary Organs of the Kangaroo,” Linn. Trans., vol. xvi. p. 62, pi. 2. fig. 1, 5.
676 PROFESSOR OWEN ON THE MARSUPIAL POUCHES, MAMMARY GLANDS,
is associated with so great a development of the inverted tegumentary fold, as to make
the mammary relation seem a very subordinate and reduced one. But in the Marsu-
pial series there is a gradation ; and both in Thylacinus and in the small dorsigerous
Opossums of South America ( Didel'phys dorsigera, D. murina , D. pusilla , &c.), the mar-
supial structure, if shown at all, is represented by a pair of shallow semilunar fossse,
with their concave outlets opposite to each other, as in Echidna.
In this comparison the distinctive peculiarity of the parts in the terrestrial Mono-
treme is the absence of a teat, or of any rudiment of such : no part of the fundus of the
pouch is again everted, produced, or folded about the terminal ducts of the mammary
gland, so as to form a pedicle by which the young could take hold with the mouth, and
so suspend itself and suck.
The question remains, whether the marsupial pouches of the Echidna increase with
the growth of the young 1 It is certain that they commence with the growth or
enlargement of the mammary glands preliminary to birth.
In that young specimen of female Echidna in which the glands were first discovered*,
their ducts opened upon a plane surface of the abdominal integument. In a nearly
full-grown unimpregnated female, preserved in spirits, which I examined and com-
pared with the breeding mother here described, there is also a total absence of inflected
folds of the integument where the mammary ducts terminate.
Some movement, perhaps, of these ducts in connexion with the enlargement of the
mammary lobes, under the stimulus of preparation for a coming offspring, may, with
associated growth of the abdominal integument surrounding the areola, be amongst
the physical causes of the first formation of the pouch.
It has already been remarked that the integument of the pouch, especially as it
approaches the fundus, is thinner than that covering the abdominal surface of the
body, from which the pouch is continued. Such tegumentary growth, continued with
the pressure of the part of the growing young within, may lead to a marked increase
of size ; to he reduced, perhaps, by absorption and shrinking of the skin concomitantly
with reduction of the mammary glands after the term of lactation has expired. I much
doubt, however, whether the increase of size of the pouch would ever be such as to
include and wholly conceal the young animal ; it more probably, at the later period of
lactation, serves only to admit the head or beak. Thus the ordinary condition of sucking
would be reversed in these Australian Mammals ; instead of the excretory ducts on
an everted process of integument being taken into the mouth, this is received into an
inverted pouch into which the milk is poured.
I have not hitherto met with any trace or beginning of such abdominal pouches in
the various Ornithorhynchi in which I have had occasion to note different phases of the
development of the ovaria and mammary glands f.
* Philosophical Transactions, 1832, p. 537, PI. XVII. figs. 2 & 3.
t “On the Mammary Glands of the Ornithorhynchus jparadoxus ,” Philosophical Transactions, 1832, p. 517.
PI. XY.-XYIII.
AND MAMMARY FOETUS OF THE ECHIDNA HYSTRIX.
677
A warm-blooded air-breather, compelled to seek its food in water, could not safely
carry the progeny it had brought forth in a pocket beneath its body during such quest ;
and all observers have noted the nest-making instinct of the Platypus , in which tempo-
rary and extraneous structures only the young have hitherto been found *. Mr. George
Bennett states that the nest “ appears to be found about the time of bringing forth the
young, and consists merely of dried grass, weeds, &c.” f
Whether the Echidna prepares any extraneous nest is not known. The specimen
transmitted to me by Dr. Mueller was caught in the hollow of a prostrate “ cotton tree.”
Being a terrestrial animal, she can carry her young about habitually concealed or partly
sheltered in her pouches ; and the present observations show the nearer affinity in this
respect of the Echidna to the marsupial Ly encephala. The Echidna may further mani-
fest this relationship by the more minute size of the young when born and transferred
to the pouch, as compared with the Ornithorhynchus ; but the size of the new-born or
newly-excluded young of that monotreme is unknown. The smallest specimen of a young
Ornithorhynchus which I have yet seen is that (Plate XLI. fig. 5) to which allusion has
been already made as being about two inches in length in a straight line.
The following are the comparative dimensions of this, and of the young of the female
Echidna (ib. fig. 3 (magn.), Plate XL. figs. 6-10 (nat.
size)), the subject
of the present
communication : —
Young
Young-
Ornithorhynchus.
Echidna.
in.
lin.
in.
lin.
Length from the end of the upper jaw, over the curve of
the back, to the end of the tail ....
3
9
1
10
Length from the same points in a straight line along the
abdomen
2
1
1
1
Greatest circumference of the body ....
2
9
1
o x
Length of the head
0
8i
0
4
Length of the upper mandible from the gape .
0
3
0
1*
Breadth of the upper mandible at the base
0
4
0
1
Length of the tail from the vent
0
4±
0
1
Breadth of tail at the root
0
4
0
X.
Length of the fore foot
0
3
0
2
Breadth of ditto
0
0
H
Length of the hind foot
0
4
0
l
Breadth of ditto
0
3
0
H
The circumstances under which this young Echidna
was obtained are given in
a letter
by the captor, Mr. G. O. Harris, to Dr. Mueller, dated “ Colac Forest, August 31,
1864.”
* Tom. cit. p. 533. f Trans. Zool. Soc. vol. i. pp. 247 & 253.
+ This might have been more before the body had become somewhat dried, or shrunk in rwt*,
678 PROFESSOR OWEN ON THE MARSUPIAL POUCHES, MAMMARY GLANDS,
It appears that Mr. Harris, being in Colac Forest, Victoria, on the 12th of August,
1864, his attention was attracted by his dogs to a fallen tree, in the hollow of which the
Echidna had taken refuge. “ On examining her I found the young one attached to one
teat, presenting the appearance of a miniature Porcupine *, with an absence of quills,
partially transparent, of a bright red colour.” The mother was placed in a porter-cask
with earth containing ants.
“ On Wednesday the 17th of August it still remained attached to the teat, presenting
the same appearance as when first captured, evidently in a living state. I avoided
handling it more than necessary, as it evinced signs of terror by a protrusion of the
vagina and frequently emitting urine.
•“ On Thursday, 18th of August, I emptied the earth out of the cask, to replace it with
fresh earth containing ants, and to my surprise found the young one removed from the
teat. I ‘ panned off’ the earth, as for gold, and found the young considerably shrunk.”
Mr. Harris thereupon placed it in a bottle of spirits, and transmitted it, with the
mother alive, to Dr. Mueller, Botanic Gardens, Melbourne. Mr. Harris concludes his
letter by stating, “ My dates are correct, as I keep a diary, and you may rely upon what
I have stated being authentic.”
The condition in which the young Echidna has reached me accords with the above
account. It is naked, devoid of prickles, the integument thin, but with its transparency
affected by the action of the alcohol, and somewhat wrinkled from contractions of the
tissues through the same action. The new-born Kangaroo, of similar size and con-
dition, described in the Philosophical Transactions for 1834, p. 344, Plate VII. fig. 5,
was also red, like an earthworm, “ resembling it not only in colour, but in the semi-
transparency of the integument.” Mr. Harris’s observation of the young Echidna
closely accords in this character with my own on the new-born living Kangaroo.
Mr. Harris observed the young Echidna attached to the mother, and he concluded
from analogy that the mode of attachment was as in the other land-quadrupeds of the
colony and in mammalia generally ; whereas it was kept in situ by the duplicature of
the skin, and by clinging with the precociously-developed claws of the fore feet to the
interior of the pouch. There was most assuredly no nipple : in that particular my own
scrutiny accords with the results of the examination of the recent animal by Drs.
Mueller and Rudall. What appearances suggested to them the idea of four quite
rudimentary mammary glands I have been unable to discover; the pair of large mam-
mary glands, together with the pouches into which they pour their secretion, had
escaped their observation.
The youn ^Echidna (Plate XLI. figs. 3 & 4), of which the admeasurements have been
given, resembles the young Ornithorhynchus (ib. fig. 5) in the general shape and
curvature of the body ; it also resembles the new-born Kangaroo above cited in the
proportions of the limbs to the body, in the inferior size of the hinder pair, in the
degree of development of the digits, and in the feeble indication of eyes or eyelids.
* The name by which the Echidna is commonly known to the settlers and gold-seekers of the colony.
AND MAMMAEY FCETTTS OF THE ECHIDNA HYSTKIX.
679
But the mouth is proportionally wider, and has the form of a transverse slit (Plate XL.
fig. 9, Plate XLI. fig. 4, n) ; it is not circular. Upon the upper lip (ib. fig. 4, m), in the
mid line between the two nostrils (a), is a small protuberance (e), corresponding to that
in the young of the Ornithorhynchus paradoxus (ib. fig. 5, e), and wanting the cuticle.
The tongue (ib. fig. 4, l) is broad and flat, extending to the “ rictus oris,” but very short
in proportion to that of the parent, and of a very different shape.
The traces of ears are less conspicuous than in the young Kangaroo, the conch being
little if at all developed in the mature Echidna. The tail is much shorter than in the
young Kangaroo, and shows as much proportional size as in the full-grown Echidna, in
which it is a mere stump (Plate XXXIX. c) concealed by the quills and hair.
The head is proportionally longer and more slender in the marsupial foetus of the
Echidna than in that of the Kangaroo, and already, at this early period, foreshows the
characteristic elongation and attenuation of that part in the mature animal.
The form of the mouth as a transverse slit, in Echidna as in Ornithorhynchus , is a good
monotrematous character of the young at that period, since in all true or teated marsu-
pials the mouth of the mammary foetus has a peculiar circular and tubular shape.
A scarcely visible linear cicatrix at the middle of the lower part of the abdomen is
the sole trace of umbilicus (Plate XL. fig. 9). A bifid, obtuse rudiment of penis or
clitoris (Plate XLI. fig. 3, d) projects from the fore part of the single urogenital or
cloacal aperture, and in advance of the base of the tail-stump (ib. c).
The brain, of which the largest part is the mesencephalon, chiefly consisting of a
vesicular condition of the optic lobes, has collapsed, leaving a well-defined elliptical
fossa of the integument indicative of the widely open “ fontanelle ” at the upper part of
the cranium (Plate XL. fig. 10, Plate XLI. fig. 3, o ). The skin of the shrunk body
shows folds indicative of the originally plump, well-filled abdomen.
The fore limbs (Plate XL. figs. 11 & 12), in their shortness and breadth, foreshow
the characteristics of those of the parent, which may be said, indeed, to retain in this
respect the embryonic character with superinduced breadth and strength. The digits
have already something of the adult proportions, the first or innermost of the five
(fig. 12, i) being the shortest, the others retaining nearly equal length, but graduating
shorter from the third to the fifth. The characteristic disposition of the digits is better
marked in the hind limb (ib. figs. 13 & 14), the second (ii) already being the strongest
and longest, the rest more rapidly shortening to the fifth ( v ) than in the fore leg ; the
innermost (i), agreeably with the law of closer retention of type in the embryo, though
the shortest of the five, is less disproportionately so than in the adult.
It thus appears that the exterior characters of the young animal, figured in Plates
XL. & XLI., accord with what might be expected, from the correspondingly immature
characters in Macropus and Ornithorhynchus , in the offspring of the species alleged.
In a question of this kind, as the liberal transmitters of the specimens were not them-
selves the captors or original observers of the young with the mother, every possibility
mdccclxv. 5 B
680 PEOEESSOE OWEN ON THE MAESUPIAL POUCHES, MAMMAEY GLANDS,
of error had to be considered. But I know of no pentadactyle ecaudate marsupial
animal which could have afforded a mammary or marsupial foetus with the characters of
that which Mr. Harris affirms to have discovered attached to the female Echidna, and
which he transmits to his correspondents in Melbourne as the young of that monotreme.
The condition of the mammary glands, and the presence of heretofore unobserved mar-
supia, accord moreover with her alleged maternity and with the state of development of
her offspring.
It occurred to me that an additional test might be afforded by the more essential parts
of the female organs of generation. These had been examined in a general way by
Drs. Mueller and Rudall, whose “ Notes ” have been already quoted. I proceeded,
therefore, to remove these organs (Plate XLI. fig. 1), with the rectum (ib. m), urinary
bladder (r), urogenital canal (u), and cloacal vestibule (ml).
The left ovarium (o), as in the Ornithorliynchus paradoxus , is of an oblong flattened
form, developed from the posterior division of the ovarian ligament ( i ) and corre-
sponding wall of the ovarian capsule (c) ; it consists of a rather lax stroma invested by
a smooth, thin, firm “tunica propria,” which glistens where stretched over the enlarged
ovisacs. Of these there were five, of a spherical form, most of them suspended to the
rest of the ovarium by a contracted part of the periphery, not stretched into a pedicle.
The largest had a diameter of 1^ line, the least of the five had a diameter of rather
less than one line. In the recent state, very fine vessels were spread reticularly, according
to the original dissectors, over the ovisacs. Beneath these, or nearer the ovarian liga-
ment, was a cluster of smaller ovisacs, the largest not exceeding ^rd of a line, the rest
so small as to give a granular character to the part. External to this, at the end of
the ovarium nearest the bifurcation of the ligament, was an empty ovisac (g% 2f lines
in length, and 2 lines in diameter, of a flattened pyriform shape, with a somewhat
wrinkled exterior, attached by the base, with the apex slightly tumid, and showing a
trace of a fine cicatrix. This is a “corpus luteum” or ovisac from which an ovarian
ovum had been discharged.
The oviducal branch of the ovarian ligament passes, as in the Ornithorliynchus , to the
outer angle of the wide oviducal slit or aperture (e), which occupies or forms the margin
of the ovarian pouch ( c ), opposite to that to which the ovary is attached. The ligament
spreads upon the inner wall of the infundibular part of the oviduct, and rejoins the
ovarian division of the ligament, to be continued along the oviduct, puckering up its
short Convolutions into a small compass.
The “ fallopian” aperture of the infundibulum (e), is a longitudinal slit of 9 lines in
length, with a delicate membranous border extending about a line beyond the part
where the muscular and mucous tissues of the oviduct make the thin wall of the infun-
dibulum opake ; its transparency against a dark ground, contrasting with the opake
beginning of the proper tunics of the oviduct, which nevertheless are here very thin.
No part of this delicate free margin is produced into fimbriae ; in this respect the
AND MAMMAEY ECETTTS OF THE ECHIDNA HYSTEIX.
679
Echidna accords with the Ornithorhynchus, and equally manifests the character by
which the Monotremes differ from the Marsupials*.
The infundibular dilatation suddenly contracts about an inch from the opening into a
“ fallopian tube,” about a line in diameter, which is puckered up into four or five short
close coils. The oviduct, after a slight contraction, suddenly expands into the uterus
(ib. d ). This is about 2 inches long, and appears to have been about 6 lines in diameter,
before being cut open. It commences by a short well-marked band, convex outwards,
and then proceeds nearly straight, the pair converging to the urogenital compartment,
slightly contracting at its termination, which projects, as an “ os tincse ” (ib. s'), into the
side of the fundus of that division of the cloaca.
The tunics of the uterus are, externally, the peritoneum (ib. fig. 2, a), which is attached
by a lax cellulosity to the “ tunica propria” (b) ; this, with its fibrous or muscular layer,
is thin, not exceeding ^th of a line in the present specimen. The inner layer of the
uterine wall ( c ) is the thickest, and chiefly composes it, consisting of delicate vascular
lamellae stretched transversely between the fibrous layer and the fine smooth lining
membrane ( d ), the whole being of a pulpy consistence, and doubtless in the recent
animal highly vascular, especially in the impregnated state.
The lining membrane was thrown into delicate irregular rugae, which assumed the
longitudinal direction at the “cervix” or contracted terminal part of the uterus. It is
laid open in the left uterus ; a style (s) is passed through it in the right uterus.
The orifice in the 44 os tincae” was a puckered slit, about a line in extent ; below it, on
a produced or papillose part of the prominence, was the small circular orifice of the
ureter; a fine hair is passed through each of these tubes in fig. 1, u, Plate XLI.
The right ovarium (o'), was proportionally more developed and larger than in the
Ornithorhynchus paradoxus \ three ovisacs were enlarged and attached to the stroma,
as in the left ovarium ; and there was also a compressed ovisac (g), similar in size and
shape to that in the left side, and exhibiting an apical cicatrix; whence it is to be
inferred that, in this instance, the right as well as the left ovarium had furnished an
impregnated ovum ; and the near equality of size and close similarity of structure and
condition of the right oviduct and uterus equally evinced that they had participated in
the last operations of the season of generation.
Figure 2 gives a magnified view of the structure of the right uterine walls, as seen in
transverse section.
The urinary bladder (r), opened into the middle of the fundus of the urogenital com-
partment, as indicated by the stylet (r, fig. 1, Plate XLI.), the uterine orifices intervening
between the vesicular one and those of the ureters, as in the Ornithorhynchus paradoxus.
* See Philosophical Transactions, 1834, Plate YI. fig. 1- — “fimbriae” of Kangaroo” ; and art. Marsupialia,
Cyclop, of Anatomy and Physiology, vol. iii. fig. 137, “fimbriae” still more remarkably developed in the
Wombat ( Phascolomys ). The absence of these fimbriae, and the resemblance of the true abdominal orifice of
the oviduct to that of the ovarian pouch, or to an ordinary duplication of membrane, appear to have prevented
its recognition by Drs. M. and R.
5 b 2
682 PROFESSOR OWEN ON THE MARSUPIAL POUCHES, MAMMARY GLANDS,
The urogenital canal is 1 inch 4 lines in length, and about 9 lines in diameter : its
inner surface shows by some coarse wavy longitudinal rugae its capacity for dilatation.
The rectum was here of great width ; it terminated by a contracted puckered aper-
ture (m'), in the back part of the beginning of the vestibule, behind the aperture of com-
munication of the urogenital with the vestibular canal. The distal half of the vesti-
bule is lined by a denser and less vascular epithelium than the proximal one.
I conclude from these appearances that the present Echidna had produced two young,
of which one only was secured ; and that, either, one was left in a nest in the fallen
hollow tree, while the other was imbibing milk from the pouch ; or that, if she had
carried a mammary foetus in each pouch prior to her capture, one had fallen out in the
scuffle that drove her from her place of shelter and concealment. The slight difference
in size between the right and left mammary glands may relate to the longer continuance
of the left one in functional activity, after the loss of the young from the right pouch.
The chief points in the generative economy of the Monotremes which still remain to
be determined by actual observation are —
1. The manner of copulation.
2. The season of copulation.
3. The period of gestation.
4. The nature and succession of the temporary structures for the nourishment and
respiration of the foetus prior to birth or exclusion.
5. The size, condition, and powers of the young at the time of birth or exclusion.
6. The period during which the young requires the lacteal nourishment.
7. The age at which the animal attains its full size.
In respect to the second point : as Mr. Harms caught the female Echidna with the
young, about an inch in length, on the 12th of August, she may be impregnated at the
latter end of June or in July. Females killed in the last week of July and the first
week of August, in the Province of Victoria, would be most likely to afford the capital
facts noted under the fourth head ; viz. the impregnated ovum in utero showing some
stage of embryonal development in the spiny terrestrial Monotreme. As to the hairy
and aquatic Ornithorhynchus , the impregnated females in which ova were found in the
uterus, of small size, and prior to the formation of the embryo, were caught on the 6th
and 7th of October*. Young OrnithorJiynchi , measuring in length in a straight line
1 inch and ffhs, were found in the nest on the 8th of December. The period of im-
pregnation is, therefore, in this species, in the locality of the Murrumbidgee River,
probably the latter end of September or beginning of October. Females captured in
the latter half of October and in the month of November, would be most likely to have
ova in utero exhibiting stages of embryonal development.
On this point I have been favoured with the following letter, one of a kind including
most which reach me from Australia on the subject, exciting, instead of allaying,
curiosity.
* See figure of the impregnated specimen in Philosophical Transactions, 1834, Plate XSY. a, a'.
AND MAMMARY FOETUS OF THE ECHIDNA HYSTRIX.
683
“ "Wood’s Point, September, 21st, 1864.
“ To Professor R Owen,
“ Sir, — I have great pleasure in being able to inform you of a very interesting disco-
very in the economy of the Ornithorhynchus paradoxus, and one which I have no doubt
you will hail with delight. About ten months ago, a female Platypus was captured in
the River Goulbum by some workman who gave it to the Gold-Receiver of this district.
He, to prevent its escape, tied a cord to its leg and put it into a gin-case, where it
remained during the night. The next morning, when he came to look at it, he found
that it had laid two eggs. They were about the size of a crow’s egg, and were white,
soft and compressible, being without shell or anything approaching to a calcareous
covering.
“ I had an opportunity of examining them externally, and I found no evidence of
their having had any recent vascular connexion with the maternal organs ; but I am
sorry to say that I never had a chance of examining their contents, as, on inquiring for
them a day or two afterwards, I found they had been thrown away, much to my chagrin
and disappointment.
“ The animal itself was afterwards killed (next day), and I was told that numerous
ova [in the words of my informant ‘ eggs’] were found in it, in various stages of develop-
ment, which in the aggregate somewhat resembled a bunch of grapes ; but this I can-
not personally vouch for.
“ It may appear to you a matter of surprise that I did not examine more minutely
this most interesting animal ; but I am sorry to say that the same spirit that dictated
the throwing away of the eggs, prevented me making a more detailed investigation.
“ I am in hopes that I shall be able to get another pregnant specimen, if so, I shall
have much pleasure in sending it to you for your inspection.
I have the honour to be, Sir,
“ Your obedient Servant,
“ Jno. Nicholson, M.D., &c.”
Wood’s Point, Victoria, Australia.”
By a following mail I was favoured by my esteemed correspondent, Dr. Mueller,
with a letter from the “Gold-Receiver” referred to by Dr. Nicholson, in reply to
inquiries which vague reports of the occurrence had induced Dr. Mueller to make.
“ Wood’s Point, September 25, 1864.
“Dear Sir, — In reply to your inquiries relative to the Ornithorhynclius paradoxus, I
must in the first place correct an erroneous impression which the newspaper paragraph
has conveyed.
“ The Platypus is not now in my possession, and the eggs were layed the day after its
capture. The animal was captured in the Goulburn and given to me. It was then
fastened by a cord in a gin-case, and on examining it the next morning the two eggs
were found in the bottom of the box, both of them having undoubtedly been laid
684 PROFESSOR OWEN ON THE MARSUPIAL POUCHES, MAMMARY GLANDS,
during the night. In the course of the day the creature was killed by a would be scien-
tific friend of mine, with the intention of preserving its skin ; and on opening the body
the ovaries were found to be clustered with ova in different stages of growth ; but none
of them so large as the eggs which were laid. These eggs were white, soft, and with-
out shell, easily compressible, and about the size of a crow’s egg.
“ Not being sufficiently versed in the subject I am not prepared to say whether these
eggs might not have been abortions caused by fear, but there was no appearance on the
surface of their ever having been vascularly connected with the maternal uterus, and
reviewing all the facts observed I should undoubtedly say that the animal was oviparous.
“ I am, dear Sir,
“ Yours faithfully,
(Signed) “ Geo. J. Rumby.”
Dr. Mueller, in transmitting me the foregoing copy of the Gold-Receiver’s letter,
writes (November 25th, 1864), “ Since writing to you by last mail I have received the
enclosed letter respecting the Ornithorhynchus having proved to be ‘ oviparous .’ How are
all these statements to be reconciled]”
Assuming the fact of the oviposition, in the month of December 1863 (Dr. Nicholson
writes of the occurrence as having happened “ about ten months” before the date of his
letter, September 21, 1864) by a female Ornithorhynchus , of two ova, about the size of a
crow’s egg, “ white, soft, compressible, without shell or anything approaching to a calca-
reous covering,” the question is — What did they contain 1 Had the unvascular chorion
been cut or torn open, an embryo or a yelk might have been seen. Better still would it
have been if both ova had been at once immersed in a bottle of whatever colourless
alcoholic liquor might be at hand. Probably no medical man had ever an opportunity
or a chance of settling a point in Comparative Physiology of more interest, and with less
trouble, than the gentleman who was privileged to be the first person to see and handle
the new-laid eggs of the Ornithorhynchus paradoxus.
For the reasons given in my Memoir of 1834*, I concluded that the Monotremes were
not “ oviparous” in the sense of the author of the memoir in the ‘ Annales des Sciences
Naturelles,’ vol. xviii. (1 829)*^, but that they were ovo-viviparous, and in a way or degree
more nearly resembling the generation of the Viper and Salamander than occurs in the
Marsupialia.
The young Viper is provided with a specially and temporarily developed premaxillary
tooth for lacerating the soft, but tough, shell of its egg, and so liberating itself J. From
this analogy I imagine that the young Monotremes may be provided with a horny or
epidermal process or spine upon the internasal tubercle, for the same purpose. This
temporary tubercle is obviously homologous with the hard knob on the upper mandible
* “ On the Ova of the Ornithorhynchus paradoxus ,” Philosophical Transactions, vol. cxxiv. p. 555.
f R. E. Grant, “ (Eufs de l’Ornithorhynque,” Ann. des Sciences Nat. 1829.
+ W einland, in Muller’s Archiv fur Physiologie, 1841.
AND MAMMARY DCETTJS OF THE ECHIDNA HYSTRIX.
685
of chelonians and birds, by which they break their way through the harder calcareous
covering of their externally hatched embryo.
Some modification of epiderm has been removed from the tubercle in the young
Echidna (Plate XLI. fig. 11, e ), as in the young Ornithorhynchus *.
Desckiption op the Plates.
PLATE XXXIX.
*>
Female Echidna {Echidna Hystrix , Cuv.), two-thirds nat. size.
a. Left “ Marsupial ” or “ Mammary ” pouch, with young as seen therein.
b. Right ditto empty.
c. Tail-stump of Echidna.
d. Outlet of cloacal vestibule.
e. Young or “ mammary foetus,” as removed from the pouch ; two-thirds nat. size.
PLATE XL.
Fig. 1. Section of abdominal integument, with mammary glands of the Echidna exposed
from the inner side.
a. Left mammary gland ; a'. Right mammary gland.
b. Ducts converging to fundus of mammary pouch.
d, d'. Part of “ panniculus carnosus ” acting as compressor of the gland.
e. Fascia forming a capsule of the gland, reflected.
f Skin of abdomen.
Fig. 2. Section of abdominal integument, and left mammary gland and pouch.
Fig. 3. Section of abdominal integument, and right mammary gland and pouch.
c. Cavity of pouch ; the other letters as in figure 1.
Fig. 4. Orifice of mammary pouch, expanded to expose the mammary areola.
Fig. 5. Mammary areola magnified to show the orifices of the lacteal ducts, and p, seba-
ceous papillse.
Fig. 6. Young or “mammary foetus” of Echidna Hystrix : nat. size: side view.
Fig. 7. Ditto : front view.
Fig. 8. Ditto : back view.
Fig. 9. Ditto : under view.
Fig. 10. Ditto: upper view.
Figs. 11 & 12. Ditto : fore-foot magnified.
Figs. 13 & 14. Ditto: hind-foot magnified.
* Transactions of the Zoological Society, vol. i. pi. xxxiii. fig. 8.
686
PEOFESSOE OWEN ON THE ECHIDNA HYSTEIX.
PLATE XLI.
Fig. 1. Female organs of Echidna Eystrix ; letters explained in the text.
Fig. 2. Section of uterus : magnified ; ditto.
Fig. 3. Young of Echidna Eystrix: twice nat. size; ditto.
Fig. 4. Ditto: mouth and end of upper jaw: five times nat. size: — «, nostril; inter-
narial tubercle ; m, upper lip ; n, lower lip ; Z, tip of tongue.
Fig. 5. Young of Ornitliorhynchus paradoxus: — a, nostril; b , eye-orifice; c, ear-orifice;
e, internarial tubercle ; relatively smaller than in fig. 3, as being in progress
of disappearance in a more advanced young one.
Fkol. Trans. MDCCCLXV TlateXXX IX
J.WcJf del
Pful. Trans . MD CCC13CV, PlateY, L
R-Owen.F.RS. del.
Edwin H. Williams, El.S. Sc.
Phil. Trans. MDCCCL Tf, Plate XL1
Pig. 5
Fig.4<
Fig 3.
R. Owen,F.R.S. del.
Edwin M Williams F.L.S^Sc,
[ 687 ]
XVI. On the Influence of Physical and Chemical Agents upon Blood ; with special
reference to the mutual action of the Blood and the Bespiratory Gases.
By George Harley, M.D. , Fellow of the Boyal College of Physicians , Professor
of Medical Jurisprudence in University College , London. Communicated by Pro-
fessor Sharpe y, M.D., Sec. B.S.
Received March 3, — Read March 10, 1864.
In order to prevent repetition, as well as to facilitate the understanding of the researches
about to be described, it is deemed advisable at once to give a brief explanation of the
manner in which the experiments were conducted. In the first place, it may be men-
tioned that all the gas-analyses herein detailed were made in strict accordance with
the justly celebrated method of Professor Bunsen, so ably explained in his work on
Gasometry. In the second place, the blood employed in the experiments was always
obtained from apparently healthy animals, and with the few exceptions, presently to be
alluded to, operated upon while still perfectly fresh. In the third place, the apparatus
used in the majority of the experiments consisted of a graduated glass receiver of the
shape represented in the accompanying figure (A), the neck of which was drawn out to
a fine capillary tube, upon the end of which was placed a piece of caoutchouc tubing.
mdccclxv. 5 c
688
PROFESSOR HARLEY ON THE INFLUENCE OF
After a certain quantity of blood (usually 62 cubic centimetres) or other fluid was
introduced at the mouth (b), the latter was firmly closed with a tightly fitting cork, and
the remaining opening (f) secured by a ligature, so that all communication between
the external atmosphere and the gas confined with the blood was effectually interrupted.
When the experiment was completed, the gas was obtained from the receiver by
plunging the lower end of the vessel into mercury, and carefully removing the cork,
while it was still retained in that position, so that neither the contained gas could find
an exit, nor the external air obtain admittance. A tube (B) partly filled with mercury
was now carefully adjusted to the mouth of the receiver by a well-fitting cork ( d ); the
receiver was next removed from the mercury trough, and a fine capillary glass tube (C)
inserted into the free end of its piece of caoutchouc tubing ; the end of this tube was
dipped under the surface of mercury and the ligature at f removed. The mercury in
B immediately descended and forced the atmospheric air out of the tube C, which in
its turn became filled with gas from the receiver. The end of the tube C was then
brought under an inverted eudiometer filled with mercury, and more of that liquid
poured into B until sufficient gas was obtained from the receiver for analysis. In the
fourth place, the temperature of the human body was imitated by employing an artificial
digesting apparatus which could be readily kept at a constant heat of 38° C.
Lastly, the experiments were performed in a gas-laboratory, the temperature of which
varied but slightly during the twenty-four hours, and their performance was thereby
greatly facilitated. For the use of this laboratory I am deeply indebted to the President
and Council of University College, London, who most liberally placed it at my entire
disposal during a period of three years.
As indicated by the title of the paper, the series of researches about to be detailed is
devoted to the influence of some physical and chemical agents on the blood with refe-
rence to its action on the respiratory gases. For the sake of convenience, the communi-
cation is divided into two parts.
The first includes the influence of the following physical agents.
a. The effect of simple diffusion in producing a change in the mixture of gases con-
fined with blood.
b. The influence of motion on the changes reciprocally exerted upon each other by
blood and atmospheric air.
c. The influence of time on the interchange of the respiratory gases.
d. The effect of temperature on the same, from 0° C. to 38° C.
e. The influence of the age of the blood, including the effect of the putrefaction.
The second part of the communication is devoted to the consideration of the influence
of chemical agents, especially such as are usually denominated powerful poisons. These
agents are selected from the three kingdoms.
a. Animal.
b. Vegetable, and
c. Mineral.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
689
In relating the experiments, I have sedulously avoided advancing any theories with
regard to the mode of action of any of the agents studied, and on one or two occasions
only has even as much as a hint been given that the results obtained might in any way
tend to the elucidation of the action of remedies or the mode of death by poison. The
reticence in this instance has arisen from the circumstance that several of the results are
so novel and at the same time so pregnant with material for theorizing, that the indi-
vidual facts might soon be lost sight of in a sea of speculation. It appears to me there-
fore that the ends of science will be much better served if I confine myself to a descrip-
tion of the bare data, rather than propound the numerous theories which the different
results suggest, and which, although they might make the paper more interesting, could
not in reality add to its true value.
I may also mention that the material is so arranged as to be easily accessible, each
fact having been made as far as possible independent of its associates, in order that
future inquirers may find no difficulty in isolating any particular result they may desire
specially to investigate. Moreover, the progressive details of each experiment are given
in the form of an appendix, so that the initiated investigator can follow it with facility
through its different stages, either for the purposes of comparison or verification *.
Past I. — INFLUENCE OF PHYSICAL AGENTS.
(a) The effect of Diffusion in modifying the composition of atmospheric air confined
with fresh blood.
The influence of both venous and arterial blood was studied.
1st. As regards arterial blood.
A certain quantity of arterial blood was allowed to flow directly from the femoral
artery of a healthy dog into a glass receiver, and after being carefully secured along with
100 per cent, of atmospheric air, was placed aside in a warm room during forty-eight
hours. At the end of this time the receiver was opened in the manner already described,
and a certain quantity of its gas removed for analysis.
* The Appendix is deposited for reference in the Archives of the Loyal Society. The first analysis only is
given in detail as a specimen.
5 C 2
690
PROFESSOR HARLEY ON THE INFLUENCE OF
No. 1. — Air from arterial blood of Dog.
Volume.
Barometric
pressure.
Temperature.
Vol. at 0° C. and
1 metre pressure.
For carbonic acid.
Air employed
140-3
718-7
7-7
98-08
After absorption of carbonic acid
139-0
719-4
5-8
97-91
For oxygen.
Air employed...
244-2
359-0
6-2
85-72
After addition of hydrogen
331-8
449-9
6-1
146-00
After explosion
258-0
372-9
4-5
94-64
No. 1. — In 100 parts of air.
Oxygen . .
Carbonic acid
Nitrogen .
1 9-928'>
0 ^g0>Total oxygen 20-111
79-889
2nd. As regards venous blood.
A certain quantity of venous blood was allowed to flow directly from the jugular vein
of an apparently healthy dog into a glass receiver. It was then secured along with 100
per cent, of atmospheric air, and kept, as in the previous case, in a room of moderate
temperature during forty-eight hours. The gas from this blood gave the following
result : —
No. 2. — In 100 parts of air.
Total oxygen 20-557
Oxygen . . . 18-400
Carbonic acid . 2-157
Nitrogen . . . 79-443
As the composition of ordinary atmospheric air is supposed to be : —
l 100 parts.
“}TM oxygen 20-962
79-038
it appears from the results of these experiments that both arterial and venous blood act
in precisely the same manner, the amount alone of their action being different. As
might have been expected, the venous blood has yielded by simple diffusion a much
greater amount of carbonic acid than the arterial blood. Moreover, under the same
circumstances it has absorbed a much larger quantity of oxygen.
Oxygen . .
Carbonic acid .
Nitrogen .
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
691
In 100 parts.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
Atmospheric air operated upon
20-960
0-002
79-038
20-962
Air after forty-eight hours’ contact
with —
Arterial blood
19*928
0-183
79*889
20-111
Venous blood
18-400
2-157
79-443
20-557
The total amount of oxygen is in both cases slightly diminished, and with this diminu-
tion the proportion of nitrogen, which is calculated by “ difference,” is necessarily
increased.
(b) Effect of Motion on the action of blood on atmospheric air.
The mere effect of motion was attempted to be ascertained in the following manner.
Two portions of the same blood of a calf, after being thoroughly arterialized by being
repeatedly shaken with renewed portions of air, were confined in receivers with 100 per
cent, of air, and treated in a precisely similar manner during forty-eight hours, except
that one blood had a small quantity of quicksilver added to it in order to render its
agitation more complete. The following were the results obtained.
Pure blood of calf, forty-eight hours’ action with 100 per cent, of atmospheric air: —
No. 3. — In 100 parts of air.
Oxygen
Carbonic acid .
Nitrogen . .
^.Jgj-Total oxygen 18-22
81-78
Same blood shaken with quicksilver, forty-eight hours’ action with 100 per cent of air,
yielded the following result : —
No. 4. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen
4-11)
7*63/
88-76
•Total oxygen 11-64
Oxygen.
Carbonic acid.
Nitrogen.
Ox-blood
15-14
3-08
81-78
Ox- blood plus quicksilver...
4-1
7*53
88-76
The difference between these results is very striking, so much so, that it was thought
advisable to discover if the mercury had not exerted some undefined chemical action,
either on the air or blood, in addition to its mere mechanical influence in facilitating
their thorough mixing. With the view of solving this question, other two portions of
blood were taken, and while to one a small quantity of quicksilver was added, the other
692
PROFESSOR HARLEY ON THE INFLUENCE OF
had an equal amount of powdered glass mixed with it. Both receivers were put aside
in a place where the temperature never exceeded 7° C. At the end of five days, during
which period they were repeatedly shaken, the air was analyzed for carbonic* acid.
No. 5. — In 100 parts of air.
Carbonic acid from blood, plus quicksilver . . I- 72
„ „ „ „ „ glass . . . T30
As it appeared from this and the foregoing that the action of the mercury was some-
thing more than merely mechanical, in order to ascertain the influence of motion alone,
two equal portions of the same fresh venous blood from an ox were placed in receivers
with similar proportions of atmospheric air (1 vol. of blood to 3 vols. air) and kept at a
temperature of 30° C. during six hours. In each receiver was placed a small quantity of
powdered glass, in order the more effectually, when the receivers were shaken, to mix the
blood. The first receiver was shaken only three minutes at a time, the second five. In
all other respects they were treated exactly alike*.
Air after being enclosed during six hours at a temperature of 30° with venous blood
shaken with glass, three minutes at a time. Result : —
No. 6. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
J^j-Total oxygen 18-20
81-80
Same blood as the preceding, under precisely the same circumstances, but shaken
during five minutes at a time. Result : —
No. 7. — In 100 parts of air.
Oxygen ....
Carbonic acid . .
Nitrogen . . .
It thus appears that the mere effect
gases interchanged.
1 4.40}
4-44) Total ox^en 18'93
81-07
of motion has an influence on the amount of
(c) Influence of Time on the interchange of gases between the blood and air.
It was found from a series of experiments (as might have been expected from our
knowledge of the respiratory process) that the longer air is retained in contact with
blood, the greater is the change worked in its chemical composition. Thus it was found
* It may be bere mentioned that during tbe course of these experiments it was found necessary, in order to
arrive at anything like correct results, not only to use (in the comparative experiments) the blood of the same
species of animal, but of the same bleeding ; as for some cause or other, the state of the digestion or the health
of the animal, different bleedings invariably gave slight differences in result.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
693
that if the ordinary respiratory act was imitated as closely as possible, by simply passing
a current of pure atmospheric air through a series of twenty-four blown glass bulbs,
partly filled with defibrinated arterialized ox-blood, kept in a digestive apparatus so con-
structed as to be capable of being retained at the temperature of the human body, the
air underwent the following change.
Air after passing through twenty-four bulbs half filled with blood, at a temperature of
38° C., gave the following results: —
No. 8. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen .
20-61)
0-96/Total °Wn 21-57
78-43
It is thus seen that the blood out of the body exerts a similar chemical action upon
air brought in contact with it as it does in the lungs of the living animal, at least so far
as the interchange of gases is concerned. The next point being to retain the air longer
in contact with the blood at the same temperature, the following experiment was per-
formed.
Defibrinated fresh ox-blood, after being well arterialized by shaking it with renewed
portions of air, was kept during 1| hour in contact with 100 per cent, of pure atmo-
spheric air at a temperature of 38° C.
No. 9. — In 100 parts of air.
Oxygen ... .19 76)^^ 0Xygen 22-68
Carbonic acid . . 2-921
Nitrogen . . . 77’32
Another portion of the same blood as the preceding was heated in precisely the same
manner, but instead of being kept only 1^ hour in contact with the air it was retained
34 hours.
No. 10. — In 100 parts of air.
^ [-Total oxygen 22-87
Oxygen. . . . 18-80
Carbonic acid .
Nitrogen . . . 77-13
The effect of time is well illustrated in these three examples, for with the single
exception of the period during which the air was in contact with the blood, all the other
factors were identical. By placing the results in a tabular form, the influence of time is
more easily appreciated.
Oxygen.
Carbonic acid.
Nitrogen.
Air employed
20-96
00-00
79-04
After a few seconds’ action by blood
20-61
00-96
78-57
After 1^ hour’s action
19-76
02-92
77-32
After 3^ hours’ action
18-80
04-28
76-92
694
PROFESS OB HARLEY ON THE INFLUENCE OF
It is here seen that the reciprocal action of blood and air is gradual, and one requiring
time, a fact which supports the view that the inspired air gradually combines with the
constituents of the blood in the torrent of the circulation.
(d) Influence of Temperature.
1st. As regards the amount of carbonic acid exhaled.
Three equal portions of freshly-defibrinated ox-blood, after being well arterialized by
repeated agitation, were put into receivers with 100 per cent, of air, and kept at the
following different temperatures during 3J hours : —
1st. At 0° C.
2nd. At 26° C.
3rd. At 38° C.
No. 11. — The results when calculated yield in 100 parts of air, —
1st. Temperature 0° C.=0-00 carbonic acid.
2nd. „ 26°C. = 3-08
3rd. „ 38° C.=4-07
Thus the higher the temperature, up to a certain point, the greater is the amount of
carbonic acid exhaled.
In order to see if the same rule is applicable to the oxidation of the constituents of
the blood, other three portions of defibrinated ox-blood were taken, and after being
treated in the usual way, were kept at different temperatures during twenty-four hours.
(a) In an ice cellar.
(b) In a room at 12° C.
(c) In an artificial digesting apparatus heated to 38° C.
(a) Ox-blood with 100 per cent, of air, twenty-four hours’ action at 0° C. Result
No. 12. — In 100 parts of air.
Nitrogen . . . 81-98
This experiment was made in foggy weather.
(b) Ox-blood with 100 per cent, of air, twenty-four hours’ action at 12° C. Result
No. 13. — In 100 parts of air.
Oxygen. . . . 12‘54lm , „ ^
Carbonic acid. . 2.77}Total oxygen 15-31
Nitrogen . . . 74*69
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
695
( c ) Ox-blood with 100 per cent, of air, twenty-four hours’ action at 38° C.
No. 14. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
22-4o}T°tal oxygen 22'40
77-60
Result : —
The amount of carbonic acid exhaled in this case seems very extraordinary, neverthe-
less I believe that it is perfectly correct, for another portion of the same blood, used as
a controlling experiment, yielded to within a fraction of the same amount of carbonic
acid. The fraction of difference, too, was an excess, being 22-6 instead of 22*4. Thus
24 hours at 38° C. Result: —
No. 15. — In 100 parts of air.
Carbonic acid =22* 6.
As the weather was exceedingly foggy at the time these experiments were made, it
was deemed advisable to analyze the fog in order to ascertain how much carbonic acid
it contained, lest the extraordinary results obtained in the last two experiments might
be due to that cause, or to some disease in the blood.
No. 16. — Result of an analysis of fog in 100 parts of air.
Carbonic acid =0-52.
This is the greatest amount of carbonic acid 1 ever obtained from London fog, and
large though it be, it is still far too small a quantity to account for the results in the
last two cases.
By placing the different effects of temperature in a tabular form, the influence exerted
by that factor over the chemical changes occurring in blood will be still better appreciated.
Defibrinated ox-blood.
Oxygen.
Carbonic acid.
Nitrogen.
Temperature 0° C. 24 hours
17*43
00-59
81-98
„ 12° C. „
12*54
02-77
74-69
„ 38° C. „
00-00
22-40
77-60
The influence of temperature on the interchange of gases is equally well illustrated by
comparing the results of experiment 13 with that of experiment 10, when it will be
seen that 3J hours’ action at a temperature of 38° C. (the temperature of the animal
body) yields much more carbonic acid than 24 hours’ action at a temperature of 12° C.
100 per cent, of air with ox-blood.
Oxygen.
Carbonic acid.
Nitrogen.
24 hours’ action at 12° C
12-54
2-77
74-69
3i „ „ 38° C
18-80
4-07
77-13
The effect of temperature on the individual constituents of the blood was also studied,
mdccclxv. 5 D
696
PROFESSOR HARLEY ON THE INFLUENCE OF
but only with red coagulum was it found sufficiently well marked to merit being noticed
here. Three equal portions of coagulum from fresh ox-blood were confined with 100
per cent, of atmospheric air during six hours at the following temperatures.
(a) At 21° C. ; ( b ) at 30° C. ; (c) at 36° C., with the following results: —
Amount of carbonic acid in 100 parts of air in
No. 17. ( a ) 6 hours at temperature of 21° C.=2-34 carbonic acid.
No. 18. (b) „ „ 30° C.=5T8
No. 19. (c) „ „ 36° C.=7-29
It is thus seen that the amount of carbonic acid exhaled by red-blood coagulum in-
creases with the temperature as far as the experiment went, namely from 21° to 36° C.
2nd. As regards the influence of cold in retarding the reciprocal chemical changes
which occur between atmospheric air and blood, a striking proof of which is to be found
in the result of the following experiment.
Two ounces of arterial blood were allowed to flow directly from the carotid artery of a
dog into a glass receiver, which in order still further to ensure its being thoroughly oxi-
dized, as well as to prevent its coagulating into a solid mass, was shaken with renewed por-
tions of air during two hours ; a small quantity of fluid mercury being also employed to
prevent the coagulation. After this treatment the receiver was firmly corked and kept
(with occasional agitation) in a room the temperature of which never exceeded 7° C.
during five whole days.
Dog’s arterial blood five days at a temperature under 7° C.* Result:
-In 100 parts of air.
12-62]
^9|Total oxygen 14*34
No. 20.-
Oxygen .
Carbonic acid .
Nitrogen . . . 85-66
On its removal from the receiver, the blood, although dark in colour, had a perfectly
fresh odour. The diminished temperature not only retarded the chemical changes, which
for the sake of convenience we may term “ respiratory,” but also those decompositions
and transformations so intimately connected with oxidation, to which the name “ putre-
faction” has been given.
(e) Influence of the age of the blood.
The putrefactive changes occurring in blood are exceedingly curious, and perhaps it
may not be out of place if some of them be here alluded to.
The following series of experiments were made on sheep’s blood. The first began
within two hours after the blood was withdrawn from the animal, the last after it had
stood 688 hours.
* The first part of this experiment has been already given, but it is here again repeated in order to save the
time of the reader in referring back to it, and so it is occasionally done with some others.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
697
Two ounces of well defibrinated sheep’s blood, after being arterialized by constant agi-
tation with renewed portions of air during twenty minutes, were put into a receiver with
100 per cent, of atmospheric air and kept during twenty-four hours in a room the tem-
perature of which varied from 6° to 12° C. Result : —
No. 21. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
^.QgjTotal oxygen 15*81
84*19
A similar portion of the same blood as the preceding, after being exposed to the air in
an open glass vessel during sixty hours, was treated in an exactly similar manner, and then
placed in a receiver with 100 per cent, of air. The temperature of the room during the
time of the experiment varied, as before, from 6° to 12° C. The blood after the sixty
hours’ exposure had become of a dark venous hue, but it still arterialized readily on being
agitated with fresh portions of air. It smelt slightly, as if putrefaction had begun.
Under the microscope the red blood-corpuscles were perfectly distinct. Result : —
No. 22.-
Oxygen . . .
Carbonic acid .
Nitrogen .
-In 100 parts of air.
2*88
3-69J
93*43
Total oxygen 6*57
This blood, which was of a bright arterial hue when put into the receiver with the
air, at the end of the twenty-four hours had again resumed the venous colour. On
shaking the vessel the blood looked as if it were decomposed. It remained of a dark
purple colour on the sides of the glass, although the blood was at this time eighty-four
hours old. On removing it from the receiver, and shaking it with renewed portions of
atmospheric air, it again assumed the arterial tint. After the sheep’s blood was 136 hours
old it was of a dark purple colour, and when a thin layer was spread over a white plate
it looked quite granular. When examined with the microscope, the blood-corpuscles
were still found perfectly distinct in their outline, and on being measured they averaged
4ijo millim. (j oTo 6 o inch) in diameter. The blood arterialized readily on being shaken
with fresh air.
A third portion of this blood was taken and subjected in every respect to precisely the
same treatment as in the two preceding cases. Result : —
No. 23. — In 100 parts of air.
Oxygen. . . . 1*01'
Carbonic acid . . 4*31,
Nitroeen . . . 94*68
Total
0XJi
5*32
A fourth portion from the same blood, after it was 184 hours old, still became of an
5d2
698
PROFESSOR HARLEY ON THE INFLUENCE OF
arterial hue when well shaken with air, although it had a film of fungi on its surface,
and smelt strongly as if it were putrid. When once arterialized it looked exactly like
freshly-drawn blood, and when examined microscopically it showed the red blood-corpus-
cles as well as if it had only been a day old. Indeed, by its previous history, and smell
alone, could a stranger have had any idea of its having been drawn from the animal more
than a few hours. The fourth portion was treated in a similar manner, and for the same
length of time as the others.
In this case, for some cause or other, no explosion could be obtained, even after the
addition of 50 per cent, of explosive gas. Result : —
No. 24. — In 100 parts of air.
Oxygen .... OOO
Carbonic acid . . 4-91
Nitrogen . . . 95'09
The blood after 304 hours’ exposure still arterialized when well agitated with air. On
using the microscope, the corpuscles were found to be distinct, though not so numerous
as at first. They were best seen without adding water. Indeed the addition of water
almost totally destroyed them by instantly dissolving their attenuated walls and allowing
their contents to escape.
A fifth portion of this blood was treated precisely as the preceding examples with 100
per cent, of air in one of the usual glass receivers, the temperature of the room varying,
as before, from 6° to 12° C.
The oxygen, if there was any, was not estimated.
No. 25. — In 100 parts of air.
Carbonic acid . . 4’99
The blood after being kept 688 hours still arterialized on being thoroughly shaken
with renewed portions of air. It was fearfully fetid, and contained numbers of living
animalcules of the Vibrio class. The red corpuscles were still distinct, though in greatly
diminished quantity, from numbers of them having become broken up and dissolved *.
The usual quantity of this blood was put into the receiver with 100 per cent, of air
and treated during twenty-four hours in the ordinary manner.
No. 26. — In 100 parts of airf.
Carbonic acid . . 5T1
* This series of experiments was performed in the winter months, but in one conducted during the months
of April, Hay, June, and July, I was able to detect blood-corpuscles in the putrid fluid after it was three months
and seven days old ; so that blood-corpuscles appear to be much more persistent bodies than is in general
imagined.
t The oxygen was also estimated in this case, but unfortunately without a controlling experiment being at
the same time performed, so it is of little value. The following is the result of the analysis.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
699
No. 27. — In 100 parts of air.
Oxygen . . 2'10
The analysis of the gas after twenty-four hours’ contact with the blood therefore stands
thus :
In 100 parts of air.
Oxygen .... 2TCh
n , . ., r n ITotal oxygen 7*21
Carbonic acid . . 5T1J
Nitrogen . . . 92*79
As it is rather troublesome to carry the results of these analyses in the mind, I shall
now give them in a tabular form, when it will be at once evident to any one who has
given attention to the subject, that the chemical changes exerted upon air by putrefac-
tion, in so far as they are here studied, are very different from the true respiratory ones
previously alluded to.
In 100 parts of air.
Oxygen.
Carbonic acid.
Nitrogen.
1st portion
of fresh blood
13-76
2-05
84-19
2nd
same „ 60 hours old ...
2-88
3-69
93-43
3rd
„ „ 136 „
1-01
4-31
94-68
4th „
„ „ 184
0-00
4-91
95-09
5th „
„ 304
—
4-99
—
6th „
„ „ 688
—
5-11
—
It is here seen that the process of putrefaction exerts, up to a certain extent, the same
effect on the absorption of oxygen and exhalation of carbonic acid by the constituents
of the blood, as was observed to be exercised by an increase of temperature. Thus we
find that the older the blood becomes the more oxygen it extracts from the air, and the
more carbonic acid does it at the same time yield. Here, however, the analogy stops.
For we find that while in those cases where the normal respiratory action is such as to
have produced the exhalation of more than 5 per cent, of carbonic acid, the oxygen
does not entirely disappear from the air (see experiments 35 and 58, Part II.), and in
those again where the oxygen has been entirely taken up by the blood it is again all
returned to the atmosphere, as seen in the results of experiment 14 related at page 695.
During the putrefactive process, on the other hand, the amount of oxygen absorbed is
exceedingly great in proportion to the quantity of carbonic acid exhaled.
Part II.— INFLUENCE OF CHEMICAL AGENTS ON THE BLOOD.
Effect of Animal Peoducts.
Snake Poison.
For the purpose of studying the effect of animal poisons upon the reciprocal action of
blood and atmospheric air, I obtained, through the kindness of the late Mr. Mitchell,
700
PROFESSOR HARLEY ON THE INFLUENCE OF
Secretary to the Zoological Gardens, the loan of two African Puff Adders. They were
3 feet in length, and about 8 inches in circumference at the thickest part.
The physiological action of animal poisons being as yet imperfectly understood, before
alluding to the special action of the poison on the blood, I shall briefly relate the history
of one of the experiments.
The experiments were performed at University College, in the presence of my col-
leagues, Professors Sharpey, Ellis, and Williamson. The serpents had eaten nothing
during eight days, so it was supposed that their poison-bags were well charged with
venom.
A large dog was bitten by one of the snakes over the right eye. The immediate
appearance of a drop of blood indicated the position of the wound. In three minutes
the dog became very restless, and gave a low whine as if in pain. After moving about
the room for ten minutes searching for a comfortable place to lie down on, he placed
himself in the coolest part of the chamber, and laid his head on the cold stones, as if to
relieve headache. He moaned as if in distress. In a quarter of an hour after he
received his wound the pulse had fallen from 100 to 64 per minute. As the effects of
the poison passed away the pulse gradually recovered, and in twenty-five minutes it was
again as high as 96 per minute.
In one hour after being bitten the dog had so far got over the effects of the poison
as to be able to run about.
The serpent was once more allowed to bite him. The same train of symptoms again
appeared, but in a more intense degree, and within twenty-five minutes he had become
insensible. He looked as if in a profound sleep, from which he could not be roused.
The respirations were 40 per minute, and the pulse so feeble in the femoral artery that
it was found impossible to count it. The pupils were dilated.
Half an hour after being bitten the second time convulsive twitchings began to appear
in the fore limbs and in the muscles of the neck. In ten minutes more the whole body
became convulsed. The limbs were stretched out, and the head jerked backwards.
During the convulsions the respirations rose to 90 per minute ; but they subsided to 40
in the intervals. The temperature of the rectum gradually fell in the course of one
hour and a half from 38° to 35° C. In two hours the respirations were reduced to 9 per
minute, the animal temperature at the same time being 34° C. The pulse was com-
pletely imperceptible ; even the heart’s action could not be felt through the ribs.
In two hours and a quarter the animal appeared to be dead; but on making an
incision into the thorax he gave a gasp. After waiting some time, without observing
any further sign of life, another incision was made, when he again gasped, but only
once. On opening the thorax the heart was found pulsating at the rate of 60 per
minute ; it was, however, more like a quivering than a true pulsation. The tissues of
this and of the other animals killed by the puff adders presented a very strange appear-
ance, namely, numerous extravasations of blood throughout the body, some small, some
large. For example, in this animal there was an extravasation of blood into the ante-
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
701
rior mediastinum, and into the tissue of the pericardium, but no effusion into the peri-
cardium itself. There were extravasations along all the great veins, into the cellular
tissue of the pancreas, throughout the diaphragm, beneath the peritoneum, and all over
the abdomen. The interior of the latter, indeed, looked exactly as if it had been
sprinkled over with blood. A similar condition also existed in the subcutaneous
cellular tissue. In fact, had the history of the case not been known, it would have
been supposed that the animal had laboured under a severe form of purpura hsemor-
rhagica.
In the neighbourhood of the wounds there was great swelling, as well as an extrava-
sation of brownish putrid looking blood. Everything pointed to blood poisoning.
The state of the spleen merits special attention. It was of a dark bluish olive tint ;
quite peculiar. I have never met with a similar hue in any other case of poisoning.
On exposure to the air the blood became arterialized, and the organ then lost the
strange appearance. The muscles were darker than usual. In the course of a few
hours they passed into a state of rigor mortis, which was quite distinct seventeen hours
after death. The brain was very anaemic, and showed no signs of extravasation.
In the course of a few weeks after this experiment was made three of the puff adders
died and were sent to me for examination. They were in exceedingly good condition,
and beyond having fatty livers there was no apparent disease. On removing the poison
from their poison bags and allowing it slowly to evaporate on a glass slide, beautiful
crystals were observed to form in it similar to the specimens represented in the accom-
panying figure.
Fig. 2.
Crystals from puff-adder poison.
This crystalline body seems to be peculiar to this species of snake, as I failed to
obtain it from the common adder, as well as from two specimens of Cobra, one from
Morocco, and one from Egypt.
702
PROFESSOR HARLEY ON THE INFLUENCE OF
Examination of the Blood.
Under the microscope, the red corpuscles were in general normal in appearance.
There were, however, a number of three-cornered ones to be seen, like what is some-
times met with in the half-putrid blood of fish. There was also an excess of white
corpuscles, which might have been due to the animal being in full digestion.
After the blood had stood for some hours in a glass vessel, although not coagulated,
it had deposited the corpuscles and left a layer of serum on the top*. Shaken with
air it arterialized readily. It contained 0*235 gramme (3-64 grains) of urea per ounce.
No sugar could be detected in it, yet after standing a couple of days it became quite
acid. A quantity of this blood, after being thoroughly arterialized, was put into a
receiver with 100 per cent, of air, and in order to make the experiment as exact as
possible, a healthy dog was sacrificed, and a similar quantity of its blood treated in
exactly the same manner. As this experiment was performed during the season of the
year when the days were short, and I could not work in the laboratory after four o’clock,
I carried the receivers home with me, and repeatedly agitated them during the evening,
and pretty far on into the night.
After twenty-four hours’ action the analyses of the gases gave the following results -
1st. Blood of healthy dog. Result : —
No. 28. — In 100 parts of air.
Oxygen . . . 19'TOOWj 20.109
Carbonic acid . 0*409J
Nitrogen . . . 79*891
2nd. Blood of dog poisoned by puff adder. Result : —
No. 29. — In 100 parts of air.
Oxygen
Carbonic acid
Nitrogen .
17*09
1*09.
•Total oxygen 18*18
81*82
It is here observed that there has been a marked difference in the action of the two
bloods. The puff-adder poison seems to have accelerated the transformations and
decompositions upon which the absorption of oxygen and the exhalation of carbonic
acid by the blood depend. By placing the results in the form of a Table, this fact is
rendered still more apparent.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 parts of atmospheric air
20-960
0-002
79*038
20-962
Ditto, after being acted on by pure blood
19*700
0-409
79*891
20-109
Ditto, after being acted on by poisoned blood..
17*09
1-09
81-82
18-18
* On opening the other animals some hours after death the blood was found to he fluid, hut it coagulated
after its withdrawal from the body. It formed a jelly rather than a clot. There seemed to be a marked dimi-
nution in the amount of fibrin, as well as a thinning of the blood, in all the cases.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
703
As these results are probably different from what most persons may have expected, it
may be advisable briefly to relate the controlling experiments, at least so much of them
as refer to the exhalation of carbonic acid. They were performed in a precisely similar
manner, except that the proportion of blood to that of air was as one to three.
1st. Healthy dog. 1 volume of pure blood to 3 volumes of air. Twenty-four hours’
action at temperature under 12° C. Result : —
No. 30. — In 100 parts of air.
Carbonic acid . . . . O' 38
2nd. Blood of dog poisoned by puff adder. 1 volume of blood to 3 volumes of air.
Twenty-four hours’ action at temperature under 12° C. Result : —
No. 31. — In 100 parts of air.
Carbonic acid . . . . 0-78
Here too it is seen that, although treated in every respect alike, the blood of the
poisoned dog exhaled more carbonic acid than that of the healthy animal.
Uric Acid.
As uric acid, although a normal constituent of the animal body, may be regarded in
the light of an animal poison, inasmuch as it is an effete product, it was experimented
with in the following manner.
Two portions of well defibrinated sheep-blood, after being thoroughly arterialized,
were placed in receivers with 100 per cent, of atmospheric air. To one of them was
added 0-2 gramme (3T grains) of pure uric acid prepared from human urine (the uric
acid was thoroughly pounded in distilled water and then mixed with the blood in
a mortar ; 62 grammes of blood was the quantity employed). The pure blood was
treated in the same way, but with distilled water alone. After twenty-four hours’
action under identical circumstances, the air of the receivers was analyzed.
Air after being in contact with pure blood of sheep during twenty-four hours. Re-
sult : —
No. 32. — In 100 parts of air.
Oxygen . . . aS-901Total i5.85
Carbonic acid . 1*95 J
Nitrogen . . . 84 T5
Air after being in contact with sheep’s blood to which uric acid was added. Result : —
No. 33. — In 100 parts of air.
Oxygen . . . 13-171Total oxygen 15-79
Carbonic acid . 2*62 J
Nitrogen . . . 84-21
5 E
MDCCCLXV.
704
PROFESSOR HARLEY ON THE INFLUENCE OF
It is thus seen that the presence of an abnormal amount of uric acid in blood hastens
the chemical decompositions and transformations upon which the absorption of oxygen
and exhalation of carbonic acid depend.
Animal Sugar.
As an illustration of the action of animal sugar upon blood, the following experi-
ment may be cited. To a third portion (62 grammes) of the same blood as was used
in the two preceding experiments, 04 gramme (6 -2 grains) of sugar obtained from the
urine of a diabetic patient were added. The sugar was first made into a syrup with a
small quantity of distilled water, and then mixed in a mortar with the blood. In order
to avoid all possibility of error, the pure blood, as before stated, was treated in the same
way with distilled water alone. Result : —
No. 34. — In 100 parts of air.
Oxygen ... 15 01 j/potaj oxygen 16-62
Carbonic acid . 1*61 /
Nitrogen . . . 83-38
It is here seen that the animal sugar had the effect of retarding the respiratory
changes produced in atmospheric air by blood, less carbonic acid being exhaled, and a
smaller amount of oxygen absorbed ; just the opposite effect as was observed to follow
the addition of uric acid to blood.
The subjoined Table shows this more distinctly.
Sheep’s blood. Twenty-four hours. 100 per cent, of air.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
Pure blood
13-90
1-95
84-15
15-85
Blood plus uric acid
13-17
2-62
84-21
15-79
Blood plus sugar
15-01
1-61
83-38
16-62
Action of Vegetable Products on Blood.
Hydrocyanic Acid.
The following are examples of the influence of hydrocyanic acid on the action of
blood on the respiratory gases.
A quantity of perfectly fresh ox-blood was taken and carefully switched until freed,
as far as possible, of its fibrin. After being thoroughly arterialized, it was then divided
into several portions of 62 grammes each, and treated in the usual manner in a room of
moderate temperature during twenty-four hours.
Pure defibrinated ox-blood with 100 per cent, of atmospheric air. Twenty-four hours’
action. Result : —
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
705
No. 35. — In 100 parts of air.
Oxygen . . . 10-42jTotal oxygen 16.47
Carbonic acid . . 5-05 J
Nitrogen . . . 84"53
Defibrinated ox-blood with 6 drops (20 per cent, strength) of hydrocyanic acid. 100
per cent, of air. Twenty-four hours’ action. Result : —
No. 36. — In 100 parts of air.
Oxygen . . . 16-321Total 18.23
Carbonic acid . 1*91 J
Nitrogen . . . 81-77
It is thus seen that the effect of hydrocyanic acid is to retard those transformations
and decompositions upon which the interchange of the respiratory gases depend. The
effect is well marked in this case, but it is even more so in a case of poisoning in the
human subject, which I shall immediately refer to ; meanwhile the results of these two
analyses are —
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 per cent, of air from pure ox-blood
10-42
5-05
84-53
15-47
Ditto plus hydrocyanic acid
16-32
1-91
81-77
18-23
Action of Hydrocyanic Acid on Human Blood.
A quantity of blood was removed from the heart and great vessels of a healthy well-
developed young woman, aged 19 years, who died within half an hour after swallowing
a couple of drachms of bitter almond oil. The blood was still fluid forty-eight hours
after death, and yielded a small quantity of hydrocyanic acid by distillation. A portion
of the blood, after being thoroughly arterialized by agitation with renewed portions of
air, was put into a receiver with 100 per cent, of atmospheric air, and kept twenty-four
hours (with occasional agitation) in a room of an average temperature of 15° C. At
the end of the twenty-four hours the air confined with the blood was analyzed, with the
subjoined result : —
No. 37. — In 100 parts of air.
Oxygen 19-56
Carbonic acid .... O'OO
Nitrogen 80-44
It is here seen that the effect of hydrocyanic acid is the same in the body as out
of it, namely, to arrest respiratory changes.
5 e 2
706
PROFESSOR HARLEY ON THE INFLUENCE OF
Nicotine.
Various experiments were performed with nicotine, and it was invariably found to
produce the same result ; namely, to retard the normal oxidation processes in blood,
and at the same time to diminish the exhalation of carbonic acid. The following expe-
riment may be quoted as an illustration of the fact.
Two portions (62 grammes) of defibrinated ox-blood, after being thoroughly arte-
rialized, were placed in receivers with 100 per cent, of atmospheric air, and both were
treated during twenty-four hours exactly alike, except that to one was added 6 drops of
chemically pure nicotine.
Gas from pure ox-blood after twenty-four hours’ action with 100 per cent, of atmo-
spheric air. Result : —
No. 38. — In 100 parts of air.
Oxygen . . .14 66 0Xygen 17*04
Carbonic acid . . 2-38.1
Nitrogen . . . 82-96
Gas from ox-blood after twenty-four hours’ action with 6 drops of nicotine. 100 per
cent, of atmospheric air. Result : —
No. 39. — In 100 parts of air.
Oxygen . . . 19-601
Carbonic acid . 1*49 J
Nitrogen . . . 78-91
Total oxygen 21-09
It is thus seen, as was before said, that nicotine diminishes the power of the blood to
take up oxygen and give off carbonic acid, and thereby become fitted for the purposes
of nutrition.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 per cent, of air from pure ox-blood
14-66
2-38
82-96
17-04
Ditto plus nicotine
19-60
1-49
78-91
21-09
Woorara Poison.
Two portions of defibrinated sheep’s blood, after being thoroughly arterialized, were
placed in receivers with 100 per cent, of atmospheric air, and kept, with occasional
shaking, at a temperature of 15° C. during twenty-four hours. The treatment of the
two portions of blood only differed in this respect, that to one nothing was added, while
0-01 gramme of woorara was put into the other. The amount of blood in each case
was 62 grammes.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
707
Air from pure sheep’s blood. Twenty-four hours’ action.
Result : —
No. 40. — In 100 parts of air.
100 per cent, of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
12-42)
o-7o}Total oxysen 13-12
86-88
Air from sheep’s blood plus woorara. Twenty-four hours’ action,
air. Result : —
No. 41. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
^TGo}^0^ oxy§en
81-72
100 per cent, of
It is thus seen that woorara has the peculiar effect of diminishing oxidation, and at
the same time increasing the exhalation of carbonic acid gas.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 per cent, of air from purel
sheep’s blood J
12-42
0-70
86-88
13-12
Ditto plus woorara
16-68
1-60
81-72
18-28
For the purpose of studying the action of woorara upon the blood of the living
animal, I injected under the skin of a dog an aqueous solution of five grains of the
poison*. The animal soon became paralyzed and died, as is usual in those cases, from
the cessation of the respiratory movements. The heart’s action continued vigorous
for some time after apparent death : a portion of this dog’s blood was then taken and
thoroughly arterialized by repeatedly shaking it with renewed quantities of air. The
blood was then enclosed in a receiver with 100 per cent, of atmospheric air, and treated
in the usual way during twenty-four hours. The result of the analysis was as follows : —
No. 42. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
1 glj-Total oxygen 20-19
79-81
If we compare this result with the analysis of air from the blood of a healthy dog
(No. 28) already given (page 702), we shall find that the effect of the woorara has been
like that of snake poison, to increase the chemical decompositions and transformations
in the blood, upon which the exhalation of carbonic acid depend.
* For the woorara employed on this occasion I am indebted to the liberality of Charles Watertox, Esq., of
Walton Hall, the well-known author of the ‘ Wanderings.’ He obtained it in Guiana in 1812, and though it
is consequently half a century old, it is still an exceedingly active poison.
708
PROFESSOR HARLEY ON THE INFLUENCE OF
In 100 parts of air.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
Healthy blood of dog
19*700
0-409
79*891
20-109
Blood of dog poisoned with woorara ...
18-680
1-510
79*810
20-190
It will be observed that there is a slight discrepancy between the amount of oxygen
absorbed in this and the other experiment on the action of woorara out of the body ;
for here the oxidation has been greater than in the healthy animal. This most pro-
bably arises, however, from some accidental cause, due to the blood being taken from
different animals and not operated on in the same day. Unfortunately it is impossible
to operate on both healthy and poisoned blood of the same animal at the same time,
so that all our experiments of comparison on the blood of living auimals are liable to
the source of error arising from the state of the body and the constitutional peculiarity
of the animal. My former statement regarding the action of woorara, namely, that it
diminishes oxidation and increases the exhalation of carbonic acid, at least in sheep’s
blood, is I have little doubt correct, as I have invariably found it to be so. I might
here quote other experiments in proof of this assertion, but in order to prevent unneces-
sary repetition, shall delay doing so till the action of woorara is compared with that of
other substances.
Antiar and Aconitine.
For the sake of brevity I shall take these two poisons together. As is well known,
their physiological action on the animal body is, as nearly as possible, identical. They
are both powerful cardiac poisons. So powerfully, indeed, do they act in this way,
that when given to frogs they stop the action of the heart while the animal is otherwise
sufficiently well to be able to spring about. This is the reverse of woorara, which
allows the heart’s action to continue long after the rest of the body is dead. Hence
arises the saying that we may have a dead heart in a living body with antiar and
aconitine, and a dead body with a living heart with woorara.
The result of the following experiment forcibly illustrates the truth of the latter
statement. A healthy full-grown frog was pricked with the point of a poisoned arrow,
and in the course of a few minutes its limbs gradually became paralysed. The paralysis
soon extended itself over the body, the animal ceased to breathe, and in the course of a
few minutes more was dead. On examining the heart about an hour afterwards, that
organ, and that organ alone, was found still alive. Death could not be said here to have
usurped its power, for it slowly and regularly pulsated as in life. On the following
day the heart still continued to beat although the tissues surrounding it had assumed
the appearance of death. Forty-eight hours after the animal had been poisoned its
heart still continued to act regularly, and even seventy-two hours afterwards the action
of the ventricle and auricles, though feeble, was yet distinct. On the fourth day
(ninety-six hours after death) part of the heart died, the left auricle alone continued to
pulsate. But now, not only was the frog dead, but its lower limbs were already shrunk
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
709
and withered. I then made an attempt at resuscitation, and exactly 100 hours after
the animal died I put it into a moist warm atmosphere, and there retained it till the
temperature of its body was slightly raised. This treatment had the effect of restoring
the irritability of the heart, and on touching the ventricle with a point of my pen it
resumed its pulsations, and during several minutes the contractions, first of the auricles
and then of the ventricles, continued rhythmically ; even the pulsations in the large
vessels attached to the heart also became distinctly visible, and continued so with regu-
larity for upwards of a quarter of an hour.
The chemical action of antiar and aconitine on the blood, like their physiological
action on the nervous system, are as near as possible alike. First, as regards their
influence on the exhalation of carbonic acid. Two portions of thoroughly defibrinated
and well arterialized sheep’s blood, 62 grammes each, were put into receivers with
100 per cent, of air. To the one 0-01 gramme of antiar dissolved in water was added ;
to the other a similar quantity of pure aconitine dissolved in faintly acid water. After
twenty-four hours’ action "the air in the receivers was analyzed with the following results.
Antiar'*, twenty-four hours’ action, 100 per cent, of air. Result : —
No. 43. — In 100 parts of air.
Carbonic acid . . . 2 '05.
No. 44. — Result of analysis of air from blood with aconitine in 100 parts of air.
Carbonic acid . . . 2*02.
It is thus seen that the influence of antiar and aconitine on the exhalation of carbonic
acid is very similar. I shall now quote a series of experiments in which the influence
of these substances with that of woorara is compared.
A quantity of defibrinated sheep’s blood was taken seventeen hours after the death of
the animal, and after being completely arterialized it was divided into four portions,
each of which was put into a receiver with 100 per cent, of atmospheric air. They
were all treated precisely alike, except that to one 0-092 gramme of antiar was added,
to another 0-092 gramme of aconitine, and to a third 0-092 gramme of woorara. The
fourth portion was retained pure in order to form a standard of comparison. After
twenty-four hours’ action the air was analyzed, with subjoined results.
1\ o. 4b. — Air from pure
Oxygen . . .
Carbonic acid .
Nitrogen .
12-05}Total oxygen 15 '81
84-19
* For the antiar employed in these experiments I am indebted to the kindness of Professor Shakpey.
710
PROFESSOR HARLEY ON THE INFLUENCE OF
No. 46. — Air from blood plus woorara, in 100 parts of air.
Oxygen . .
Carbonic acid .
Nitrogen . .
12.gg}Total oxygen 19-83
80-17
No. 47. — Air from blood plus antiar, in 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
1 2-98}
1 oi rTota-l oxygen 13-99
86-01
No. 48. — Air from blood plus aconitine, in 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
o!!} Total oxygen 12-96
I’oU J
87-04
By placing these results in a tabular form the comparative value of each of the factors
will be made more apparent.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 parts of air from pure blood
13-76
2-05
84-19
15-81
Blood plus woorara
16-85
2-98
80-17
19-83
„ „ antiar
12-98
1-01
86-01
13-99
„ „ aconitine
11-66
1-30
87-04
12-96
The similarity in the action of antiar and aconitine, and the dissimilarity between their
action and that of woorara, are well illustrated in the above Table. The woorara dimi-
nishes oxidation and increases the exhalation of carbonic acid. Antiar and aconitine
increase oxidation and diminish the exhalation of carbonic acid gas.
Strychnine.
In order to ascertain the influence of strychnine, a quantity of fresh calf’s blood was
shaken with renewed portions of atmospheric air until it had become thoroughly
saturated with oxygen. It was then enclosed in a receiver with 100 per cent, of ordi-
nary air, corked up, and kept in a room of moderate temperature during twenty-four
hours.
A second portion of the same blood (62 grammes) was similarly treated in every way
except that it had 0-05 gramme of strychnine added to it. During the twenty-four
hours the receivers were as usual frequently agitated to favour the mutual action of the
blood and air. At the end of this period the composition of the gas in the receivers was
found to be —
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
711
Gas from pure calf’s blood, twenty-four hours’ action with 100 per cent, of air: —
No. 49. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen .
12-10)
5-94)
81-96
■Total oxygen 18-04
Gas from calf’s blood plus strychnine, dissolved in a minimum of very dilute hydro-
chloric acid, twenty-four hours’ action with 100 per cent, of air : —
No. 50. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
17*82)
2<7gjTotal oxygen 20-55
79-45
Thus it is seen that strychnine is one of those substances possessing the strange pro-
perty of preventing the chemical decompositions and transformations of the constituents
of the blood upon which the absorption of oxygen and exhalation of carbonic acid depend.
Oxygen.
I Carbonic acid.
Nitrogen.
Total oxygen.
In 100 parts of gas from pure calf’s blood
12-10
5-94
81-96
18-04
Ditto plus strychnine
17-82
2*73
79-45
20-55
The next point to determine is, does strychnine act in the same manner on blood in
the living animal as out of it \
The results of the two following experiments seem to indicate this, but as they were
performed with the view of solving an entirely different question not requiring any con-
trolling experiments, they had none made with them, and therefore they can only be
taken for what the results of single experiments are worth.
Into the peritoneal cavity of a healthy full-grown cat was injected a solution of -^tli
of a grain of strychnine. In five minutes the animal became convulsed, and in four
minutes more it died. On opening the body eight minutes after death, some of the
blood was found already coagulated in the greater vessels, and the portion that was
fluid coagulated as soon as it flowed into a capsule. The blood had a dark purple
colour, and when shaken on the sides of a glass looked almost grumous and granular,
as if the corpuscles were broken up, and had allowed their contents to escape. Under
the microscope plenty of healthy red corpuscles were seen, many of them running into
rolls ; but besides these, although there were no broken-up cells to be seen yet there
were an unusual number of small granules in the field. The animal was fasting, never-
theless there were also a considerable number of white corpuscles present. The blood
contained 0-22 gramme of urea to the oz. (0-709 per cent.) and abundance of sugar.
Gas from blood of cat poisoned with strychnine, twenty-four hours’ action with 100
per cent, of air in a room of moderate temperature : —
mdccclxv. 5 F
712
PROFESSOR HARLEY ON THE INFLUENCE OF
No. 51. — In 100 parts of air.
Oxygen .
Carbonic acid .
Nitrogen . .
10-6o}Total 0xygen 17'63
82-37
It is thus seen that the blood of the poisoned animal yields even a smaller quantity
of carbonic acid than the blood to which strychnine has been added out of the body,
while the quantity of oxygen that has disappeared is the same in both cases.
Brucine.
Besides strychnine the alkaloid brucine is also obtained from nux vomica, and the
following experiment was made with the view of testing if it had a similar action upon
blood. The experiment in this case, however, was somewhat extended in order to com-
pare its action with that of two other substances, namely, quinine and morphia, and as
the results obtained form rather an interesting series, I shall give them consecutively.
A quantity of perfectly fresh calf’s blood, after being defibrinated and thoroughly
saturated with oxygen by repeatedly shaking it with renewed quantities of air, was
divided into several portions of 62 grammes each. To the first nothing was added ; to
the second 0-005 gramme of brucine ; to the third 0-005 gramme of quinine ; and to the
fourth 0-005 gramme of morphine : these alkaloids were all dissolved by the aid of a
minimum quantity of hydrochloric acid. The different portions were then enclosed in
receivers with 100 per cent, of air, and treated in the usual manner, with occasional
agitation, in a room of moderate temperature during twenty-four hours. At the expi-
ration of that period the air was analyzed, with the following results : —
No. 52. — The air from pure calf’s blood contains in 100 parts of air —
Oxygen . .
Carbonic acid .
Nitrogen . .
o ^j-Total oxygen 10-11
89-89
The air from the calf’s blood plus brucine contained —
No. 53. — In 100 parts of air.
Oxygen. . . . 11-631 n_
, . . , _ _ . ITotal oxygen 13-97
Carbonic acid . . 2*34 J Jb
Nitrogen . . . 86-03
It is thus seen that brucine acts like strychnine, but in a much less marked degree.
Quinine.
As has just been said, to another portion of the same blood as was employed in the
two preceding cases, 0-005 gramme of quinine was added.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
713
No. 54. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
12-05}T°tal oxygen 16'77
83-23
Morphine.
To the fourth portion of the same blood 0-005 gramme of morphine dissolved in water
acidulated with hydrochloric acid was added, and the result was as follows : —
No. 55. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
17 J7J.Total oxygen 18-17
81-83
It is thus seen that these different substances, Brucine, Quinine, and Morphine, with
hydrochloric acid as their solvent, have all acted on the blood in the same manner,
retarding oxidation, and decreasing the exhalation of carbonic acid, but in very different
degrees. By placing them in a tabular form, the difference in their respective results
will be still better appreciated.
Oxygen.
Carbonic acid.
Nitrogen.
Vol. at 0° C. and
1 metre pressure.
In 100 parts of air: —
After being acted on by pure blood
6-64
3-47
89-89
10-11
Ditto by blood plus brucine
11-63
2-34
86-03
13-97
„ „ quinine
14-72
2-05
83-23
16-77
„ „ morphine
17-17
1-00
81-83
18-17
Composition of atmospheric air employed \
in the experiments J
20-96
0-002
79*038
20-962
It ought not to be forgotten that the blood in all of these cases was not only taken
from the same animal, and the product of one bleeding, but in every respect, both before
and after being put into the receivers, subjected to precisely similar influences, under
identical conditions. The difference in the results must therefore be regarded as entirely
due to the effect of the alkaloids upon the blood.
Action of Anesthetics on Blood.
Chloroform.
From the fact that of all anaesthetics at present employed chloroform holds the first
rank, its action upon blood was carefully studied. The results obtained were exceedingly
uniform and all tending to one conclusion, namely, that this substance has a powerful
effect in retarding those chemical transformations and decompositions upon which the
process of respiration depends.
1st. As regards the visible effect of chloroform upon blood.
If 5 per cent, of pure chloroform be mixed with the freshly-drawn blood of a healthy
5 f 2
714
PROFESSOR HARLEY ON THE INFLUENCE OF
animal, it will be found that within half an hour the blood will assume a brilliant scarlet
hue. If the vessel containing it be now agitated, so as to mix the blood with atmospheric
air, a quantity of colouring-matter adheres to the sides of the glass, and on allowing it
again to stand for a few minutes, a red somewhat flocculent precipitate is deposited.
This precipitate is not hsematin alone. On the contrary, it consists of a dirty red-coloured
protein substance, whereas the dissolved or suspended pigment has a vermilion hue. If
the blood be kept at rest for some hours — laid aside during the night — it will to a certain
extent lose its brilliant colour, and assume that of the red precipitate previously spoken
of. At the same time it will be found to solidify into a gelatinous sticky paint-like mass.
If instead of 5 per cent., 50, or still better 100 per cent, of chloroform, be added to venous
blood either defibrinated or non-defibrinated, it causes it at once to assume the arterial
hue, and this is still more marked if the vessel be well agitated. The blood rapidly
solidifies and retains its vermilion tint for many hours, even days. It not unfrequently
happens that blood to which chloroform has been added crystallizes on solidifying, more
especially when only 5 per cent, of chloroform is used.
Serum is not solidified by chloroform in the same way, but it deposits a white preci-
pitate.
2nd. Microscopical appearances presented by blood after being acted upon by chloro-
form.
If 5 per cent, of chloroform be added to blood, and the mixture well shaken, it will be
found on examining it with the microscope that, although very many of the red corpuscles
have disappeared, their walls having been dissolved, and their contents escaped, the great
majority of them remain intact. Even 100 per cent, of chloroform fails to destroy totally
the blood-cells. Great numbers of the red cells are, however, destroyed, and their contents
diffused throughout the liquid. It is indeed the contents of the red corpuscles that
crystallize. The crystals are in many cases quite red. They are prismatic
in shape, and about four times as long as they are broad. The crystals
are always most readily obtained from the blood of animals that have
been poisoned with chloroform, but only after an additional quantity is
added. They are insoluble in chloroform, ether, alcohol, and water.
3rd. Chemical action of chloroform on blood.
Two equal portions of defibrinated and arterialized ox-blood, equal to
62 grammes each, were placed in receivers with 100 per cent, of atm os
pheric air, and kept in a room of moderate temperature during twenty-
four hours. Both bloods were treated precisely alike, except that while the
one was kept in its normal state, the other had three drops of chloroform added to it.
Gas from pure ox-blood, twenty-four hours’ action with 100 per cent, of atmospheric
air : —
No. 56. — In 100 parts of air.
Oxygen. . . . 10-42}
Carbonic acid . . 5-05}T°tal 0X^en 1547
Nitrogen . . . 84-53
Fig. 3.
Crystals obtained
from blood by
means of chlo-
roform.
PHYSICAL AND CHEMICAL AGENTS TJPON BLOOD.
715
Gas from ox-blood plus chloroform, twenty-four hours’ action, 100 per cent, of atmo-
spheric air : —
No. 57. — In 100 parts of air.
Oxygen . .
Carbonic acid .
Nitrogen . .
1 Q.7Ci
1<gg|Total oxygen 20-64'
79-36
This result proves that chloroform possesses the property of diminishing the power of
the constituents of the blood to unite with oxygen, and give off carbonic acid. A pre-
cisely similar result was obtained when the experiment was made on the blood of the
young animal.
Perhaps as chloroform is so important an agent I may be pardoned quoting an expe-
riment performed on the blood of the calf, which proves the correctness of the above
assertion.
Equal parts of well-oxygenated freshly-dehbrinated calf’s blood were treated during
twenty-four hours in receivers in the usual way. One was kept pure, and the other had
three drops of chloroform added to it (as in the other cases the quantity of blood employed
was 62 grammes).
Gas from pure
spheric air: —
calf’s blood, twenty-four hours’ action, with 100 per cent, of atmo-
No. 58. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
n^lTotal oxygen 18-04
0*94 J
81-96
Gas from calf’s blood plus chloroform, twenty-four hours’ action, with 100 per cent, of
atmospheric air. Result : —
No. 59. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen . .
12.3g}Total oxygen 20-93
79-07
It is thus seen that chloroform acts in the same manner on the blood of the young as
on that of the adult animal.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen. 1
In 100 parts of air from
Pure ox-blood
10-42
5-05
84-53
15-47
Ditto plus chloroform
18-76
1-88
79-36
20-64
Pure calf’s blood
12-10
5-94
81-96
18-04 1
Ditto plus chloroform
18-05
2-88
79-07
20-93
1
716
PROFESSOR HARLEY ON THE INFLUENCE OF
Ether.
The action of sulphuric ether, which is also used as an anaesthetic, upon blood is both
chemically and physically different from that of chloroform, as shown by the result of
the following experiments.
1st. Chemical effect of ether upon blood.
A quantity of ox-blood, after being defibrinated and well saturated with oxygen in the
usual way, was divided into several portions, to one of which nothing was done, while to
another 5 per cent, of sulphuric ether was added. After the different portions of blood
had been kept with 100 per cent, of atmospheric air during twenty-four hours, in a room
of moderate temperature, they yielded the subjoined results.
Gas from pure ox-blood, twenty-four hours’ action, 100 per cent, of air yielded —
No. 60. — In 100 parts.
Nitrogen . . . 86'09
Gas from ox-blood plus 5 per cent, of sulphuric ether, twenty-four hours’ action, 100
per cent, of air. Result : —
No. 61. — In 100 parts of air.
Carbonic acid . . 3'40
In the experiments with ether the amount of oxygen absorbed by the blood could not
be ascertained in consequence of the gas in the eudiometers refusing to explode. Even
after the tubes were nearly filled with explosive gas the electric spark failed to ignite
the gas, yet when the eudiometers were removed from the mercury trough, the gases
instantly and violently exploded on the application of a lighted match.
2nd. Physical effects of ether upon blood.
When 5 per cent, of ether is added to fresh blood no marked effect is observed, except
that the blood does not arterialize so readily as with chloroform. When ten, twenty, or
more per cent, is added, the difference in the physical effect of the two anaesthetics upon
blood is very striking. The etherized blood becomes clear but dark in colour, and cannot
be made to assume the perfect arterial tint, not even after prolonged agitation with
renewed portions of atmospheric air. The greater the percentage of ether the more
visible is this effect. 100 per cent, of sulphuric ether gives to blood a beautifully rich
transparent port-wine colour. When left some hours in repose, part of the ether sepa-
rates from the blood and floats as a colourless liquid on the surface, while the blood
itself still retains the rich dark hue, except the layer in immediate contact with the
ether, which appears as if it had a vermilion tint. When examined with the micro-
scope the blood-corpuscles are found to be completely destroyed, their colouring-matter
being set free.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
717
Eig. 4.
When non-defibrinated blood is employed, and the ether allowed to evaporate, the
blood solidifies, and in so doing frequently crystallizes ; but strange to say the crystals
are quite different in form from those obtained by chloroform from the same blood.
They are long needles, twelve times as long as broad, and
are sometimes so abundant that they fill up the whole
field of the microscope. The crystals are not usually so
much coloured as those of chloroform. They too are most
copious in the blood of animals poisoned by the anaesthetic.
In some healthy bloods I have entirely failed in detecting
them. The best are obtained from the blood of the dog *.
Ether, as already said, destroys the corpuscles more than
chloroform.
It is curious to notice how the effects of different sub-
stances upon blood vary. I thought, for example, that
alcohol would act like ether upon blood, whereas to my surprise its action much more
closely resembled that of chloroform, although only in a mitigated degree. Notwith-
standing that alcohol cannot properly be regarded in the light of an anaesthetic, I shall
take the liberty of here introducing an experiment upon it, seeing that it was performed
on a portion of the same blood as served for the last two examples, and was conducted
under precisely similar circumstances. Five per cent, of pure alcohol was employed.
Crystals obtained from blood by
means of ether.
Alcohol.
Gas from ox-blood plus alcohol, after twenty-four hours’ action, on 100 per cent, of
atmospheric air : —
No. 62. — In 100 parts of air.
Oxygen . . .
Carbonic acid .
Nitrogen .
16-591 1
2-38jr°tal oxygen 18-9 1
81-03
By placing the results of these last three experiments in a tabular form the difference
they present will be better seen.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 parts of air from
Pure blood
10-58
3-33
86-09
14-91
Ditto plus ether
Ditto plus alcohol
16-59
3-40
2-38
81-03
18-97
It is thus seen that while the action of ether is to increase, or at least not to diminish
* Magnificently large prismatic crystals are readily obtained by adding equal parts of ether to the blood of
dogs poisoned by the vapour of chloroform. They are of a fine red colour, and many of them appear to be
formed of bundles of needle-shaped crystals. Sometimes almost the whole blood crystallizes.
718
PROFESSOR HARLEY ON THE INFLUENCE OF
the transformations occurring in blood upon which the exhalation of carbonic acid
depends, that of alcohol, on the other hand, is to restrain these, as well as to diminish
the consumption of oxygen : — a similar effect, it will be remembered, to that which
occurs with chloroform ; the only difference being that the action of alcohol is very much
less powerful, for a less quantity of chloroform produces a much greater effect.
Physical effect of Alcohol upon Blood.
When blood is shaken with 10 per cent, or more of alcohol it becomes of a light brick-
red hue. The albumen is coagulated and subsides to the bottom of the vessel. No
amount of shaking with renewed portions of air will properly arterialize blood mixed with
alcohol, nor have I ever obtained any crystals from blood so treated, not even from that
of animals poisoned by chloroform. Alcohol does not destroy the blood-corpuscles nor
set the hsematin free.
Amylene.
* Some years ago amylene was proposed as an anaesthetic for the purpose of annulling
pain in surgical operations, but owing to its disagreeable odour, or some other cause, it
has never come into general use. Several experiments were made with this substance.
1st. As regards its physical action upon blood.
When five per cent, of amylene is added to fresh blood, and the mixture well shaken,
the blood assumes a dark-red tint, and does not arterialize readily. When 100 per cent,
of the anaesthetic is employed, the blood becomes quite black, and when spread out in a
thin layer has a dirty brownish-red appearance. It cannot now be made to arterialize at
all. If the mixture be allowed to stand for twenty-four hours, the amylene in great part
separates from the blood, and floats in a clear layer on its surface. The blood, however,
still retains its black, thin, tarry-like aspect.
When .examined with the microscope, the red corpuscles are found beautifully distinct ;
none appear to be destroyed, and no blood-crystals are to be found. Indeed the forma-
tion of the crystals seems to be in proportion to the destruction of the corpuscles.
2nd. Chemical action of amylene upon blood.
Two portions of defibrinated sheep’s blood, after being saturated with oxygen in the
usual manner, were placed in receivers, the one with nothing, the other with four
drops of amylene to the 62 grammes of blood. After twenty-four hours’ action the
gases were analyzed in the usual way ; but on attempting to estimate the oxygen in the
air enclosed with the amylene, it was found impossible to obtain an explosion, not only
after the mere addition of hydrogen, but after a large amount of explosive gas had been
added to the mixture ; and what was more extraordinary still, the electric spark even
failed to produce any explosion after the sulphuric acid and potash balls had been
employed. On inverting the eudiometer the gas was found to smell strongly of amy-
lene, and there can be little doubt but that its presence prevented the explosion taking
place. The analysis of the gas, as far as it went, was as follows : —
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
719
Gas from sheep’s blood plus amylene, twenty-four hours’ action, 100 per cent, of atmo-
spheric air : —
No. 63. — In 100 parts of air.
Carbonic acid 0-62
Whereas the air from pure blood gave quite a different result.
Gas from pure sheep’s blood after twenty-four hours’ action, 100 per cent, of air : —
No. 64. — In 100 parts of air.
Carbonic acid 3*17
It thus appears that amylene has a marked effect in diminishing the exhalation of
carbonic acid gas.
Action of Mineral Substances on Blood.
Chloride of Mercury ( Corrosive sublimate).
The experiments with mineral products were in general conducted in the same
manner as those with other substances. In the present instance, however, the experi-
ment was like some of the exceptions previously related, slightly modified, and instead
of employing defibrinated blood, the blood was put into the receivers direct from the
animal. Calf’s arterial blood was used in this case, and as it slightly coagulated in the
vessels, it was found necessary to have them well shaken (before being definitely closed)
until the coagula were all broken up. While to one of the portions of blood nothing
was done, to the others 6 drops of a saturated aqueous solution of corrosive sublimate
were added. The quantity of blood employed in each case amounted to 40 grammes,
and the air confined with it to 150 per cent. The receivers were all treated alike,
during twenty-four hours, in a room of moderate temperature. At the end of that
time a marked difference was observed in the bloods. The pure blood still retained
its arterial tint, while that to which corrosive sublimate had been added was of an
intensely dark, almost black colour. Moreover the latter had separated into two layers,
a thin dark red liquid, and a somewhat gelatinous coagulum. The dark liquid part of
the blood felt quite sticky to the fingers.
Gas from pure calf’s blood after twenty-hours’ action with 150 per cent, of atmo-
spheric air : —
No. 65. — In 100 parts of air.
Oxygen . .
Carbonic acid
Nitrogen . .
16-57
2-15
81-28
5 G
jTotal oxygen 18*72
MDCCCLXV.
720
PROFESSOR HARLEY ON THE INFLUENCE OF
Gas from calf’s blood plus corrosive sublimate, twenty-four hours’ action, 150 per cent,
of atmospheric air : —
No. 66. — In 100 parts of air.
Oxygen
Carbonic acid .
Nitrogen . .
17-01'
3-58-.
79-89
•Total oxygen 20-59
It is thus seen that corrosive sublimate, while increasing the changes which develope
carbonic acid, has an almost negative effect on those depending upon oxidation ; if
anything rather diminishing them than otherwise.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 parts of air from pure blood
16-57
2-15
81-28
18-72
Ditto plus corrosive sublimate
17-01
3-58
79-89
20-59
I may here take occasion to mention a fact in connexion with the physiological effects
of corrosive sublimate on the animal body, which, as far as I am aware, has hitherto
escaped notice, namely, its cardiac action. As we have already seen, there exist in the
vegetable kingdom substances which, in consequence of their acting specially on the
heart and lungs, have acquired the title of cardiac and respiratory poisons; few are,
however, aware that in the mineral kingdom there are also substances to be met with,
the peculiar action of which on the animal body is such as to entitle them with equal
justice to the name of cardiac and respiratory poisons. Corrosive sublimate is an
example of the former, protosulphate of iron of the latter.
In order not to be misunderstood, I shall briefly quote the following experiments to
illustrate my meaning.
1st. As regards protosulphate of iron, a respiratory poison.
1st experiment. Into one of the jugular veins of a dog was slowly injected an aqueous
solution of 15 grains of the protosulphate of iron. In sixty seconds from the com-
mencement of the experiment (which of itself lasted about forty seconds) the animal
manifested symptoms of impending suffocation. These speedily induced a convulsion,
and the involuntary passage of the contents of the bladder and rectum, as is seen to
occur in cases of true apnoea from a mechanical obstruction to the entrance of air into
the lungs.
In eight minutes there was complete loss of sensation and voluntary motion. The
limbs were paralysed, and the animal manifested no sign of pain on being pinched.
In ten minutes the symptoms of poisoning began to pass away, and in a few minutes
more he was again upon his legs. When seen fifty minutes after the commencement of
the operation, he was running about apparently quite well.
2nd experiment. Two days later, into the other jugular vein of the same dog, was
injected an aqueous solution of 30 grains of the protosulphate of iron, double the
quantity first used. Symptoms of suffocation instantly manifested themselves. The
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
721
lungs did not act. The respiratory movements ceased. But the heart went on beating,
and continued to do so for at least three or four minutes after all attempts at respiratory
efforts had entirely stopped.
On opening the animal, the heart was found distended with fluid blood. The blood
coagulated after its withdrawal from the body. On puncturing the right ventricle, a
globule or two of air escaped ; but the organ contained no frothy air, nor was there any
reason to suppose that the air had been injected during the operation. On the con-
trary, it appeared as if it had been separated from the blood itself, as occasionally occurs
in cases where the blood-vessels are unopened. The urine of the animal contained a
large amount of the poison. It is on the above grounds that I consider that the proto-
sulphate of iron merits the title of a respiratory poison. This w7ill be made still more
apparent by comparing the foregoing with the result of the following experiment.
2nd. As regards corrosive sublimate, a cardiac poison.
Into the femoral vein of a pregnant bitch was injected an aqueous solution of five
grains of corrosive sublimate. In ten seconds the animal cried as if in pain ; in sixty
she became delirious ; and in three and a quarter minutes after the operation was com-
menced the heart stopped. Neither was there an impulse to be felt on the application
of the finger to the femoral artery, nor a sound to be heard on the application of the
ear to the thoracic walls. The animal, however, still respired, and continued to make
gasping respiratory efforts for thirty seconds more. They then ceased. In three-quar-
ters of a minute after the cessation of respiration the thorax was opened, with the view
of ascertaining the conditon of the heart. It was found still ; and neither the stimulus
of the cold an, of the point of the knife, nor of a feeble current from the galvanic
forceps caused it to pulsate.
Ten minutes after death a stronger galvanic current was applied to the organ, but
even then the portions between the points of the forceps alone contracted. No general
pulsation could be reinduced. The foetuses were alive and moving about in the uterus
twelve and a half minutes after the death of the mother.
The corrosive sublimate had acted specially upon the heart ; for the spontaneous
peristaltic movements of the intestines were well marked, and continued to be so for
twenty-two minutes. The thoracic muscles also contracted spontaneously, with a
flickering movement, for no less than thirty minutes. They even responded to the
direct application of galvanism for two hours and thirty-five minutes after the death of
the animal.
Galvanism applied to the brachial plexus fifteen minutes after death caused violent
muscular contractions in the limb supplied by it; yet, as was before said, the heart
failed to respond to mechanical and galvanic stimuli applied within a single minute
after death.
It appears to me, therefore, that corrosive sublimate merits the name of a cardiac
poison quite as much as either aconitine or antiar.
722
PROFESSOR HARLEY ON THE INFLUENCE OF
Arsenic.
In testing the action of arsenic, as in the case of corrosive sublimate, non-defihrinated
freshly-drawn arterial blood was employed, and the quantity of air with which it was
enclosed also amounted to 150 per cent. In this instance, however, dog’s instead of
calf’s blood was employed ; and in order to give to the experiment all possible exacti-
tude, while one of the portions of blood had 120 drops of a saturated aqueous solution
(by boiling) of arsenious acid added to it, the other was treated to a similar amount of
distilled water. In all other respects they were treated precisely alike, both before and
after the twenty-four hours’ action.
Gas from non-defibrinated fresh dog’s blood plus 120 drops of distilled water, twenty-
four hours’ action with 150 per cent, of atmospheric air : —
No. 67.-
Oxygen . . .
Carbonic acid .
Nitrogen . . .
-In 100 parts of air.
20-376
0-981J
78-643
l-Total
oxygen 21-357
Gas from dog’s blood plus arsenious acid, twenty-four hours’ action with 150 per cent,
of atmospheric air: —
No. 68. — In 100 parts of air.
Oxygen . .
Carbonic acid
Nitrogen . .
iTotal oxygen 21-538
0-268 J
78-562
It is thus seen that arsenious acid is one of those substances which retard the trans-
formation of the constituents of the blood on which the absorption of oxygen and exha-
lation of carbonic acid in the respiratory process depend.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 parts of air from pure dog’s blood ...
20*376
0*981
78*643
21*357
Ditto plus arsenic
21*270
0*268
78*562
21*538
Pure atmospheric air
20*960
0*002
79*038
20*962
A precisely similar result was obtained with defibrinated calf’s blood.
Tartrate of Antimony.
A quantity of well-defibrinated sheep’s blood, after being thoroughly saturated with
oxygen, was divided into several portions, and while one was left in its normal condition,
0*02 gramme of tartrate of antimony was added to another (the quantity of blood
employed in each case was 62 grammes). The blood was treated in the usual manner,
in receivers with 100 per cent, of air, during twenty-four hours.
PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
723
Gas from pure sheep’s blood, after twenty-four hours’ action with 100 per cent, of
atmospheric air: —
No. 69. — In 100 parts of air.
Oxygen ... 19 2621,^^ 0Xygen 21*08
Carbonic acid . T818J
Nitrogen . . . 78-920
Before treatment the blood contained 0-451 per cent/ of urea; after treatment it con-
tained 0-435 per cent.
Gas from sheep’s blood plus tartrate of antimony, twenty-four hours’ action, 100 per
cent, of atmospheric air : —
No. 70. — In 100 parts of air.
Oxygen . .
Carbonic acid
Nitrogen . .
20-411
2-55J
Total oxygen 22-96
77-04
Before treatment this blood contained 0-451 per cent, of urea; after treatment it
contained 0-354 per cent. In another portion of this blood, which was treated with
sulphate of zinc, there remained only 0‘28 per cent, of urea. In a series of experiments
on the effects of antimony as a slow poison, I invariably found the urine loaded with
urea, even when the animals were reduced to perfect skeletons. In the urine of a dog
that died on the forty-third day after taking half a grain of antimony daily, there was
such an amount of urea, that, on adding nitric acid, the whole urine solidified into one
mass of crystals. The liver contained neither sugar nor glucogene.
In the above case tartrate of antimony is seen to diminish oxidation, and in a very
marked degree to increase the exhalation of carbonic acid gas. The total amount of
oxygen is also increased, making it thereby appear as if oxygen had been developed
from some one or other of the constituents of the blood, either while they were being
pulled down, or built up into new compounds. The apparent increase of the oxygen
may be due, however, to another cause, namely, the disappearance of nitrogen from
the air.
Oxygen.
Carbonic acid.
Nitrogen.
Total oxygen.
In 100 parts of atmospheric air
20*960
0*002
79-038
20*962
Air from pure blood
19*262
1*818
78*920
21*080
Ditto plus antimony
20*41
2*55
77-04
22*96
This increase in the total amount of oxygen, or decrease in the amount of nitrogen,
was even much more decided in another experiment with antimony on sheep’s blood.
In it the oxygen actually amounted to 24-69 per cent., and the nitrogen stood at 75- 31
per cent.
724 ON THE INFLUENCE OF PHYSICAL AND CHEMICAL AGENTS UPON BLOOD.
In concluding this paper, it was my intention to make some remarks on the reciprocal
action of hsematin and atmospheric air ; for, as stated in a communication on the con-
dition of ox gen absorbed into the blood during respiration*, which I had the honour
of making to the Royal Society some years ago, the colouring- matter of the blood
appears to possess a more powerful effect in altering the composition of atmospheric air
than any other individual constituent of that liquid. The recent researches of Professor
Stokes, however, cause me to pause before again publishing my views on animal colour-
ing-matters. For the interesting results obtained by that gentleman with the prism,
although in accordance with my facts, may nevertheless induce me to modify my theory ;
not regarding the action, but regarding the nature of these substances. I have hitherto
held the view that all the animal pigments spring from one colourless radical, and that
the difference in tint between hsematin, urohsematin, and biliverdin was simply due to
the different stages of oxidation of the radical. It would appear, however, from the
researches of Professor Stokes, that all these substances, although closely allied, are
nevertheless chemically distinct. I consequently prefer reinvestigating the subject
before communicating to the Society the data which are at present before me.
* Proceedings of the Boyal Society, vol. viii. p. 82.
[ 725 ]
XVII. On a New Geometry of Space. By J. Plucker, of Bonn, For. Memb. B.S.
Received December 22, 1864, — Read February 2, 1865.
I. On Linear Complexes of Bight Lines.
1. Infinite space may be considered either as consisting of points or transversed by
planes. The points, in the first conception, are determined by their coordinates, by x,
y, z for instance, taken in the ordinary signification ; the planes, in the second conception,
are determined in an analogous way by their coordinates, introduced by myself into
analytical geometry, by t, u, v for instance.
The equation
tx-\-uy-\-vz-\- 1=0
represents, in regarding x, y, z as variable and t, u, v as constant, a plane by means of
its points. The three constants t, u, v are the coordinates of this plane. The same
equation, in regarding t, u, v as variable, x, y, z as constant, represents a point by means
of planes passing through it. The three constants are the coordinates of the point.
A point given by its coordinates and a point determined by its equation, or geome-
trically speaking by an infinite number of planes intersecting each other in that point,
are quite different ideas, not to be confounded with one another. That is the case also
with regard to a plane given by its coordinates and a plane represented by its equation,
or considered as containing an infinite number of points. Hence is derived a double
signification of a right line. It may be considered as the geometrical locus of points, or
described by a point moving along it, and accordingly represented by two equations in
x, y, z, each representing a plane containing that line. But it may likewise be con-
sidered as the intersection of an infinite number of planes, or as enveloped by one of
these planes, turning round it like an axis ; accordingly it is represented by two equa-
tions in t, u, v, each representing an arbitrary point of the line. The passage from one
of the two conceptions to the other is a discontinuous one*.
2. The geometrical constitution of space, hitherto referred either to points or to planes,
may as well be referred to right lines. According to the double definition of such lines,
there occurs to us a double construction of space.
In the first construction we imagine infinite space to be transversed by lines them-
selves consisting of points. An infinite number of such lines pass in all directions
through any given point ; each of these lines may be regarded as described by a moving
* According to this discontinuity, a plane curve represented by ordinary coordinates may have a conjugate
which disappears if the same curve he represented by means of line-coordinates. See “ System der analytischen
Geometrie,” n. 330.
5 H
MDCCCLXV.
726
DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
point. This constitution of space is admitted when, in optics, we consider luminous
points as sending out in all directions luminous rays, or, in mechanics, forces acting on
points in every direction.
In the second construction infinite space is likewise regarded as transversed by right
lines, but these lines are determined by means of planes passing through them. Every
plane contains an infinite number of right lines having within it every position and
direction, around each of which the plane may turn. We refer to this second concep-
tion when, in optics, we regard, instead of rays, the corresponding fronts of waves and
their consecutive intersections, or when, in mechanics, according to Poinsot’s ingenious
philosophical views, we introduce into its fundamental principles “ couples,” as well
entitled to occupy their place as ordinary forces. The instantaneous axes of rotation
are right lines of the second description.
3. In order to constitute a new geometry of space, we may fix the position of a right
line, depending upon four constants, in a different way. We might do it by means of
four given right lines, by determining, for instance, the shortest distance of any new line
from each of the four given ones. But all such conceptions were rejected, and the ordi-
nary system of axes adopted in order to fix the position in space of a right line. Thus
the new researches, indicated by the foregoing remarks, are intimately connected with
the usual methods of analytical geometry. The two fragments presented on this occasion
are only calculated to give an exact idea of the new way of proceeding, and to show its
importance, greater perhaps than it appears at first sight.
4. A right line of the first description, which we shall distinguish by the name of ray ,
may be determined by means of two of its projections. We may select the projections
within the planes XZ and YZ, in order to get, without generalizing, the greatest
symmetry obtainable, and give to their equations either the form
cc=rz- J-f,‘
y=SZ + <T,
or
(1)
(2)
tx-\-vjz= 1,
uy-\-VyZ=. 1.
In adopting the first system of equations, the four constants r, s, g>, a are the coordi-
nates of the ray : two of them, r, s, indicating its direction, the remaining two, §, <r, after
its direction is determined, giving its position in space. The ray meets the plane XY
in the point
%=§, y=°-
In adopting the second system of equations, we get, in order to determine the same
ray, the four new constants t, u, vx, vy, which likewise may be regarded as its coordi-
nates ; t and u ^equal to ^ and ^ indicating the reciprocal values of the intercepts
cut off on OX and OY by the two projections of the ray, vx and vy ^equal to
and the reciprocal values of the two intercepts cut off both on OZ.
DE. PLUCKEE ON A NEW GEOMETEY OE SPACE.
727
5. A right line of the second description, which we shall distinguish by the name of
axis, is determined by any two of its points. We may select the intersection of the axis
with the planes XZ and YZ as two such points, and represent them by the system of
equations
xt +ztv=l, )
yu-\-zuv~\, )
(3)
or by the following equally symmetrical,
t =pv-\-zs,
u—qy-\-7t.
(4)
In making use of the first two equations, the four constants x, y, zt, zu are the coordi-
nates of the axis, indicating the position of the two points within the planes XZ, YZ.
In making use of the second system of equations, p, q, zs, k are the four coordinates
of the axis, this axis being fixed by the intersections of two planes, one of which is the
plane projecting it on XY, and determined by two of the four coordinates,
t — l ?= -? U~7t—~ i
x y
while the other plane determined by the two remaining ones,
t=pv=-~v, u=qv=—%,
and represented by the equation
px+qy+Z= 0,
passes through the axis and the origin.
6. If we consider the four coordinates of a ray as variable quantities, we may in
attributing to them any given values successively obtain any ray whatever transversing
space. But in admitting that an equation takes place between the four coordinates,
rays are excluded : we say that the remaining rays constitute a complex represented hy
the equation.
In admitting two such equations existing simultaneously, those rays the coordinates
of which satisfy both equations constitute a congruency represented hy the system of
equations. A “ congruency” contains all congruent rays of two complexes, it may be
regarded as their mutual intersection. If we admit that three equations are simul-
taneously verified by the four coordinates, the corresponding rays constitute a configura-
tion (Strahlengebilde, surface reglee) represented hy the system of three equations. A
configuration may be regarded as the mutual intersection of three complexes, i. e. as
the geometrical locus of congruent rays belonging to all three complexes. Four com-
plexes or two configurations intersect each other in a limited number of rays. The
number of rays constituting a configuration, a congruency, a complex, and space, are
infinites of first, second, third, and fourth order.
7. If rays are replaced by axes, complexes, congruencies, and configurations of rays
are replaced by complexes, congruencies, and configurations of axes.
5 h 2
728
DE. PLUCKEE ON A NEW GEOMETEY OE SPACE.
8. A configuration of rays or axes, represented by three linear equations, is, according
to the choice of coordinates, either a hyperboloid or a paraboloid. Let the three
equations of a configuration of rays be
A r +Bs +C +Ef =0,1
AV+B's+C'+D'<r+E'e=0,l (5)
A"r +B"s+ C" + T>"<r + E"f = 0. J
From these equations we derive by elimination six new ones, each containing two
only of the four variables. Let them be
ar =1, (6)
eg +dff =1, (7)
a'r+c'g =1, (8)
Vs +& e=l, (9)
a"r+d"<r= 1, (10)
b"s+c"g = 1 (11)
In order to represent the configuration, the three primitive equations (5) may be
replaced by any three of the six new ones.
The equation (7) may be written thus,
cx-\-dy= 1, (7*)
x and y replacing g and a. It represents a right line within XY, intersected by the
rays of the configuration.
The equations (8) and (9) represent within XZ, YZ two points enveloped by the
projections of the rays of the configuration; consequently the rays themselves meet two
right lines passing through these points, and being parallel to OY, OZ. From the
equations (8) and (9) if written thus,
we immediately derive
c'x= 1, c'z=a\
d'y= 1, d!z—V ,
representing the two right lines.
Thus by selecting in order to represent the configuration the three equations (7), (8),
(9), and interpreting them geometrically, we have proved that all its rays intersect three
fixed right lines, one of which falls within XY, while the two remaining ones are parallel
to OY and OX. Hence these rays, meeting three right lines parallel to the same plane,
constitute a hyperbolic paraboloid.
In determining the paraboloid, we may replace any one of the three equations we
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
729
made use of by the equation (6), which indicates that all rays are parallel to a given
plane. This plane, if drawn through the origin, is represented by the equation
ax-\-by—z ,
obtained from (6) by writing -•> - instead of r, s.
It may be sufficient here to state that a configuration of rays, if represented by
three linear equations, in which the coordinates r, s, g, a are replaced by t, u, vx, vy,
becomes a hyperboloid.
9. A configuration of axes represented by three linear equations would be a para-
boloid if the coordinates x, y , zt, zu were employed, but becomes a hyperboloid if these
coordinates are replaced by p, q, ar, z. We shall here consider the last case only, and
may for that purpose directly replace the equations (6)-(ll) by the following ones: —
ap +bq = 1, (12)
ca +d»= 1, (13)
a'p +c'ar =1, . (14)
Vq +d'x= 1 (15)
a"p-\-d"z= 1, (16)
b"q+d,B = 1 (17)
Any three of these equations, involving six constants, are sufficient to determine the con-
figuration.
If, after having replaced^?, q, ar, z by
_£?, _£^, i, I,
x y x y
we regard x, y, zt, zu as variable, (14) and (15) may be written thus,
x=a!z-{-c',
y=b'z+d\
representing within the planes XZ, YZ two right lines (AA, BB') which are the locus of
points (A, B) where the axes of the configuration meet the two planes.
In regarding vr and z as coordinates of a right line, the equation (13), being written
thus,
ct-\-du=l,
represents a given point (E),
x=c, y=d ,
enveloped within XY by the projections of axes. Therefore all axes of the configura-
tion intersect a third right line (CC') parallel to OZ and meeting XY in E.
Hence we conclude that the configuration represented by the three linear equations is
a hyperboloid. Its axes meet three given lines, two of which, AA', BB', fall within
XZ, YZ, while the third, CC', is parallel to OZ.
730
DE. PLUCIvEE ON A NEW GEOMETEY OF SPACE.
The plane BOA passing through O and an axis AB is represented by the equation
The equation (12) being with regard to p and q of the first degree, indicates that all
such planes, containing the different axes of the configuration, intersect each other along
a given right line DD' passing through O. Hence all axes meet a fourth right line,
itself confined within the hyperboloid.
The complete determination of the hyperboloid presents no difficulties. We may for
instance find its centre and its axes by determining the shortest distance of any two of
the axes generating it.
10. Let a congruency either of rays or axes be represented by two linear equations.
In adding to these equations two new ones, likewise of the first degree, there exists only
one ray or axis the coordinates of which satisfy simultaneously the four linear equations.
Two new equations of this description are obtained if, among the rays or axes of the
congruency, we select those either passing through a given point, or confined within a
given plane. In the case of rays, let (fi, ?/, z') be a given point, then we get
%!=rz,Jr%,
y'=sz'~ J-<7
in order to express that all rays meet in that point. Let
t'x+u'y+v'z+ 1=0
be the equation of a given plane, then we get
ir-\-u!s-\-v— 0,
t'g-\-u'(r- {-1=0
in order to express that the rays lie within that plane, Again, in the case of axes, let
(if, u', v ') be a given plane, then we get the new linear equations
t'x + v'zt = 1 , —pv' -f- sr,
or
u'x-\-v'zu= 1, u'=qv'-\-z,
in order to express that the axis is confined within that plane. Let in regarding x/, y\ zr
as constant, t, u, v as variable,
1 = 0
represent a given point, then we get
a?p+tfq+z!= 0,
odvs-\-y'x,-\- 1 = 0
in order to express that the axes pass through that point. Hence
In a congruency represented by the system of two linear equations , there is one single
ray or axis passing through any given point of space, as there is one single ray or axis
confined within a given plane.
DE. PLUCKEE ON A NEW GrEOMETEY OF SPACE.
731
11. In order to represent a congruency of rays, we shall here make use of the coor-
dinates t, u, vx, vy. Let
At +B u +0^ +Dyy +1=0,
At + B'm + C'vx + D'Vy +1 = 0
be its two equations. By successively eliminating each coordinate, we get four equations
of the following form,
at -\-bu ~{-cvx +1 = 0,
dt -\-b'u -\-dvy +1=0,
a"t-\-c'vx+d'Vy +1=0,
b"u + dvx-\- d"Vy +1=0,
any two of which involving six constants may replace the two primitive equations, the
remaining two being derived from them.
The first two of these equations, if t , u, vx and t, u, vy be considered as plane coordi-
nates, represent two points (U, V) the coordinates of which are
x=a, y=b, z—c , . (U)
x=za', y—b\ z=d, (V)
Consequently the six constants upon which the congruency depends, if referred to the
three axes of coordinates OX, OY, OZ, are determined by means of the two points U
and Y. Hence is derived the following construction of rays of the congruency.
Trace through the two points U, V any two planes which intersect each other along a
right line confined in the plane XY, and meeting OX, OY in the points D, F. Let
E, G be the points where the two planes meet OZ. We shall get within the planes
XZ, YZ the projections of a ray of the congruency by drawing DE, FG. The ray (AC)
thereby completely determined will intersect the plane XY in the point C, the coordi-
nates of which are
x=]=OD, y=l= OF.
If a plane be traced passing simultaneously through both points U, V, both intersec-
tions E, G falling into one point A', the corresponding ray of the congruency A'C'
intersects OZ. If the right line UV be projected on YZ, XZ, the projections meet OZ
in two points A", A!". In these points OZ is intersected by the rays of the congruency
parallel to OX, OY. The ray parallel to OZ is obtained by the point C" where it meets
XY. The coordinates of C" are
x=OB", Y=OF",
D" and F" being the points where the projection of UV intersects OX and OY.
Thus occurs to us the construction of rays passing through any point of OZ and any
point of XY. We cannot go further into detail here.
732 DE. PLUCKEE ON A NEW GEOMETEY OE SPACE.
12. Again, let a congruency of axes be represented by the equations
Atf+By +C zt -\-~Dzu +1=0,
A'x + B'y + C % + B'zu + 1 = 0.
By successively eliminating zu and zt we may replace these equations by the following
two,
ax-\-by -\-czt +1 = 0,
dx-\-b'y +<+M+l=0,
the six new constants of which are derived from the primitive constants. In regarding
x, y, zh zu as point-coordinates (where z may be written instead of zt and zu), the last
equations represent two planes. The six coordinates of both planes,
t=a, u=b, v=c,
t=a', u=V , v=d,
are the six constants of the congruency, consequently the congruency is determined by
means of these two planes and the axes of coordinates.
Suppose both planes to be known. Draw any right line meeting them in M and M7,
project M on XZ and M' on YZ. The right line joining the two projections B and A
is an axis of the congruency.
If we project on>XZ and YZ any point of the right line JK along which both planes
intersect each other, the right line joining both projections, B', A', is an axis parallel to
XY. All axes obtained in that way meet, within XZ and YZ, both projections of JK.
Hence the axes of the congruency parallel to XY constitute a paraboloid. The ray
within XY is obtained by projecting the point where the traces of both planes meet on
OX and OY and joining both projections, B" and A", by a right line, See.
13. After these preliminary discussions we shall now proceed in a more systematic
way, and henceforth exclusively make use of the coordinates r, s, g, <r. When a complex
of rays is represented by the linear equation
Ar+Bs+D<r+Eg + 1 = 0, (1)
we may easily prove that the infinite number of rays passing through a given point of
space are confined within the same plane, and, conversely, that the infinite number of
rays confined within a given plane meet within the same point.
In order to select among the rays of the complex those passing through a given point
(d, y\ z '), the following two equations,
a?=rz'+G , ]
y=sz'+<r,/ 1 ’
are to be added to the equation of the complex. By eliminating g and <r we get
(A-E2>+(B-DZ>+(l+IV+Dy)=0 (3)
This equation being of the first degree with regard to the remaining variables r and s,
shows that all corresponding rays are parallel to a given plane, and therefore confined
DR. PLtJCKER ON A NEW GEOMETRY OF SPACE.
733
within the plane of that direction and passing through the point {x\ y\ z'). By replacing
in the last equation r and s by and j~j, we obtain, in order to represent that
plane, the following equation,
(A-E^-^)+(B-D^(y-y)4-(lH-E^+Dy)(2-^)=0. ... (4)
14. Again, this equation being, with regard to (x1, y\ z1), of the first degree, proves
that, conversely, all rays confined within a given plane meet in the same point of that
plane.
15. A complex the rays of which are distributed through infinite space in such a
way that in each point there meet an infinite number of rays constituting a plane, and,
conversely, that each plane contains an infinite number of rays meeting in the same
point, may be called a linear complex of rays. We may say, too, that, with regard to the
complex, points and planes of the infinite space correspond to each other ; each plane
containing all rays which meet in the point placed within it, and each point being tra-
versed by all rays which are confined within the plane passing through it.
16. A linear complex of rays is represented by the linear equation (1), but it is easily
seen that this equation is not the general equation of a linear complex. The following
considerations lead us to generalize the preceding developments and to render them by
generalizing more symmetrical.
Hitherto we determined a ray by its two projections within XZ, YZ,
x—rz- f§,
y=sz+a,
whence its third projection within XY is derived,
ry—sx—ra—s% (5)
This equation furnishes the new term (r<r—s§), which, like f and <r, depend upon r and s
as well as upon a! and y' in a linear way.
Again, from the equations
=0,
tg-\-uff-\-w= 0,
expressing that the ray (r, s, f, <r) falls within the plane (t, u, v, to) represented by the
equation
tx-\-uy~\-vz-{-tv=0*,
we deduce
w v . .
ys—t<s=(rc-so). ......... (6)
* Henceforth We shall make use of four plane-coordinates t, u, v, w, and accordingly represent a point by a
homogeneous equation. Sometimes, where symmetry and brevity require it, likewise x, y, z shall be replaced
hy £/0, 17/0, £/0. Accordingly, by introducing the four point-coordinates t, tj, (, 6, a plane is represented by
a homogeneous equation.
MDCCCLXV. ' 5 I
734
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
17. After introducing a new term containing (sg—rff), the equation of the complex
may be written thus.
Ar+Bs+C-)-D(7+Eg>+F(5§— r<r) = 0.
When, after (ra— sg) is eliminated by means of the equation
(7)
ry'—sx,=r<r—s$.
we proceed as we did in the former case [14], the following equation is obtained in order
to represent the plane corresponding to the given point ( od , y\ z'),
(A-Fy-E^X*-^)+(B+F^-D^Xy-y)+(C+E^+I^X*-^)=0. . (8)
This equation may be expanded thus,
(A-Fy-E^>+(B+r^-D2,>+(C+Ea/+Dy>=A^+By+C/, . . (9)
and reduced also to the following symmetrical form,
A(x — x') + B (y — y ) -f C(z — z') + D (y'z — z'y) + E (a/z — z'x ) + F(x!y —y'x) = 0 . (10)
18. We may directly prove that all rays confined within a given plane meet in the
same point. The equation of this plane being
t'x-\-u'y-{-v'z-\-,w'= 0, . (11)
we get, in order to express that a ray falls within that plane, the following three equa-
tions,
i}r-\-v!s-\-v' =0,
1j Q ?{/ = 0,
w's—v'a—{rG—sq)t'= 0,
each of which results from the other two. Between these equations and the equation
of the complex (r<r—sg), r and % may be eliminated. The resulting equation,
(B^-A«i'-Fw,)s + (Dif-Ew, + Fi;> + C^-Aw'-Ew'=0, . . . (12)
being linear with regard to the two remaining variables s and <r, represents a right line
parallel to OX and intersecting YZ in a point, the coordinates of which are
, Bt’-Au'—Fw1 '
Df*— Ett'— Ft/ ’ no\
, Ct'-Av'-Bw'
y—Ds-Ku'+w '
Hence all rays of the complex supposed to fall within the plane (11) intersect that right
line, and consequently meet in the same point. Two coordinates of that point are given
by the last equations, the third,
, Cu'—Bv'—DuJ }
X Dt* — Em' + Ft/ ’ /
(14)
is obtained by introducing the values of z' and y1 into the equation of the plane.
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
735
V/e may represent the point corresponding to the given plane (tf', u\ v\ w') by its
equation,
(C v! — Bv' — Dw')t — (Ctf—Av1— E w’)u + (B?f — A v! — F w')v + (Dt' — E u'+ F d)w =0, (15)
which may be written thus,
A (v'u—u'v) + B( t'v -v't)-\- C (u't — tfu) + D(t'w — w't) + E (w'u — u'w) -f- F(i/w — w'v) =0.(16)
19. It is easily seen that both equations (12) and (16) are the most general ones,
indicating the supposed correspondence between point and plane. Therefore (10) is
the most general equation of a linear complex.
20. According to the fundamental relation which characterizes a linear complex, the
plane corresponding to a given point is determined by means of any two rays passing
through that point, as the point corresponding to a given plane is determined by any
two rays confined within that plane.
Suppose P and P' to be any two points of space, and p and p' the two corresponding
planes. Let I be the right line joining both points, II the right line along which both
planes intersect each other. Draw through I any plane intersecting T I in Q, join
Q to P and P' by two right lines QP, QP'. These right lines, both passing through
points (P, P') and falling within planes (p, p') which pass through them, are rays of the
complex. The plane PQP', containing both rays and consequently containing I, corre-
sponds to the point Q, whence we conclude that planes passing through any points
Q, Q! of II intersect each other along I. Likewise it may be proved that any plane
drawn through II intersects I in the corresponding point. We shall call I and II two
right lines conjugate with regard to the linear complex , or merely conjugate lines. The
relation between two conjugate lines is a reciprocal one ; each of them may be regarded
as an axis in space around which a plane turns while the corresponding point describes
the other ; each also may be regarded as a ray, described by a moving point, the corre-
sponding plane of which turns around the other.
Each right line meeting two conjugate right lines is a ray of the complex.
To each right line of space there is a conjugate one.
If a point move along a ray of the complex , the corresponding plane — containing each
ray of the complex which passes through the point, and therefore especially the given
one — turns around the ray.
Each ray of the complex may be regarded as two coincident conjugate lines.
21. We may also connect the preceding results with the general principle of polar
reciprocity. Indeed the general equation (10), which represents the plane correspond-
ing to a given point, is not altered if x1, y\ z' and x , y, z be replaced by one another.
Consequently we may say, in introducing the denominations pole and polar plane
instead of corresponding point and plane, that the polar planes of all points of a given
plane pass through its pole, and conversely, that the poles of all planes passing through
a given point fall within the polar plane of that point. In our particular case a plane,
5 i 2
736
DE. PLiiCKEE ON A NEW GEOMETET OF SPACE.
containing its own pole, is determined by means of the poles of any two planes passing
through that pole ; likewise a point, falling within its polar plane, is determined by
means of the polar planes of any two points of its polar plane. A right line joining
any two points of space is conjugate to the right line, along which the polar planes of
both points intersect each other. If one of two conjugate right lines envelopes within
a given plane a curve, the other describes a conical surface ; the vertex of the cone falls
within the plane containing the enveloped curve. Generally if one of the two conju-
gate right lines describes a configuration, the other one likewise describes such a sur-
face. If one of the two surfaces degenerates into a cone, the other degenerates into a
plane curve*.
22. Anoint of space being given , to construct the plane which contains all rays of the
complex passing through the point.
Each ray intersecting two conjugate lines is a ray of the complex. Accordingly
the only right line , starting from a given point and meeting any two conjugate is a
ray of the complex. We obtain a new ray, starting from the same point, by means
of each new pair of conjugate lines. All such lines constituting the plane corre-
sponding to the given point, two pairs of conjugate lines are sufficient to determine
that plane.
A plane of space being given , to construct the point where meet all rays of the complex
confined within the plane.
Each right line joining the two points in which two conjugate right lines are inter-
sected by a given plane being a ray of the complex, there will be obtained, within the
given plane, as many rays as there are known pairs of conjugate lines. Any two such
pairs are sufficient in order to determine the point within the plane corresponding to it
where all rays meet.
A plane is intersected by the two lines of each conjugate pair in two points ; the right
lines joining two such points are rays of the complex converging all towards the point
which corresponds to the plane. Again, the two planes passing through a point of space
and meeting the two lines of a conjugate pair, intersect each other along a ray of the
complex confined within the plane which corresponds to the point.
23. After this geometrical digression, immediately indicated by analysis, we resume
the analytical way.
By putting in the general equation (9) of the plane corresponding to a given point
tf'=0, y'= 0, z'= 0,
we obtain
Ax+By+Cz=0, (17)
in order to represent the plane corresponding to the origin.
* The peculiar kind of polar reciprocity we meet here was first noticed by M. Mo Bins in the 10th volume of
‘ Crelle’s Journal,’ and was afterwards expounded by L. F. Magnus in his valuable work ‘ Sammlung von
Aufgaben und Lehrsatzen aus der analytischen Geometrie des Eaumes,’ pp. 139-145.
DE. PLUCKER ON A NEW GEOMETRY OE SPACE.
737
By putting successively r
y'=
af= 00,
the same equation becomes
C+E#+Dy=0, 1
B+Far-D2 = 0, 1 (18)
A-1>-Ez=0.J
Accordingly these equations represent the planes corresponding to points moved to an
infinite distance along OZ, OY, OX.
By combining each of the equations (18) with (17), we get the rays conjugate to the
axes of coordinates OZ, OY, OX, forming a triangle, the angles of which fall within the
three planes of coordinates, XY, XZ, YZ, into the corresponding points.
24. By putting
w — 00,
the equation (15), representing a point corresponding to any given point d), becomes
D£+Ew— Fw=0,
and then indicates that the point corresponding to the infinitely distant plane of space
falls itself, at an infinite distance, along a direction which may be represented by the
equations
x y z
D — E=F’
(19)
while, if rectangular coordinates were supposed,
D^+E<y+F2!=0
represents the plane perpendicular to it.
We shall call this direction the characteristic direction of the complex. It is invariably
connected with the complex.
25. By putting successively
tf = 00,
v! = 00,
— co ,
we get, in order to represent within the planes of coordinates YZ, XZ, XY, the points
corresponding to these planes, the following equations :
Cu— Bv— Dw=0, j
a-Av-Ew=0, ......... (20)
B£— Au— Fw=0. I
738
DR. PLUCKER ON A NEW GEOMETRY OF SPACE.
Accordingly the coordinates of these points are
C
B
x— 0,
y=
Z — —
C. .
A
y=o>
x=
Z~E==Z«’
B
A
z = 0,
x=
P = 5
y=Y=yv,
whence may be derived the following relation,
xvyt2u_ _ j
In putting C= — 1, the right line conjugate to OZ, if regarded as an axis, may be
determined by its four coordinates [5],
j)=A, c[— B, bt=D, ^=E.
These coordinates therefore are four of the constants of the complex
Ar-f-Bs+D<r-t-Eg+F(sg— s<r)=l.
MN conjugate to OZ remains the same whatever may be the value of F. If by putting
F equal to zero the last equation becomes a linear one, the complex is completely deter-
mined by MN conjugate to OZ.
26. The ratio of the three constants upon which the characteristic direction of the
linear complex (1) depends, D E F
remains the same if the origin be changed or the complex moved parallel to itself. But
if by turning the complex the characteristic direction simultaneously move, that ratio is
altered. One of the three constants F, E, D becomes zero if the characteristic direction
be confined within XY, XZ, YZ ; two of them disappear, F and E, F and D ; E and D
if that direction fall within OX, OY, OZ. Here the general equation becomes
Ar+Bs + C+Dff =0, 1
Ar+Bs+C+E? =0, l (22)
Ar+Bs+C+F(s§— r<r) = 0. j
27. The ratio of the three constants
A : B : C
varies it the complex be moved parallel to itself. If the plane corresponding to O pass
through OZ, OY, OX, one of the three constants C, B, A becomes zero ; if this plane
be congruent with XY, XZ, YZ, i. e. if O be the point corresponding to XY, XZ, YZ,
two constants A and B, A and C, B and C disappear, and the general equation of the
complex becomes
DR. PLUCKER ON A NEW G-EOMETRY OE SPACE. 739
D<r+Eg+F(sg — r<r)+C =0, j
D<r+Eg-}-F(sg — r<r)+Bs=0, >•••••••• (23)
D<7+Eg+F(sg — r<r)-|-Ar=0. j
28. In order to represent a linear complex by equations of the utmost simplicity, let
us take any plane XY, XZ, YZ perpendicular to the characteristic direction, and draw
through its corresponding point O the axis OZ, OY, OX. The resulting equations will
assume the following forms,
F(s§— r<r)-\-C =0, )
‘ B s +E?=0, 1 (23*)
A r +D<r=0. J
The planes corresponding to all points of a right line having the characteristic
direction are parallel to each other ; and conversely the locus of points correspond-
ing to parallel planes is a right line of that direction. Hence we conclude that there
is one fixed line, the points of which correspond to planes which are perpendicular to it.
Consequently, on the supposition of rectangular coordinates, we may in only one way
represent a linear complex by means of equations assuming the form of those above.
Q
29. In order, for instance, to get the first of these equations, which by replacing — -
by k may be written thus,
sg — r<r=k,
it will be sufficient to direct OZ along the fixed line. As no supposition is made either
with regard to the position of the origin on OZ, or to the direction of OX and OY
within the plane XY which is perpendicular to OZ, this equation will remain abso-
lutely the same if the system of coordinates be moved parallel to itself along OZ, or
turned round it. In other terms,
A linear complex of rays invariably remains the same if it be moved parallel to itself
along a fixed right line or turned round it.
The fixed right line may be called the axis of rotation , or merely the axis of the
complex.
30. We may give different geometrical interpretations to the last three equations,
involving each a characteristic property of a linear complex of rays.
Any two planes XZ, YZ intersecting each other along OZ being given, rays of space
may be determined either by their projections on both planes, or by the points where
they meet them. In the first case, if a third plane intersecting XZ, YZ along OX,
OY at right angles be drawn, there are two planes LMN, L'M'N', parallel to each other,
passing through the two projections LN, M'N, and meeting OZ, OY, OX in N and N',
M and M', L and L'. In the second supposition, denote the two points of intersec-
tion by U and Y, and their projections by U' and V'. Accordingly U'U, V'V, and U'V'
maybe regarded as the projections of UY on the planes XZ, YZ, and on OZ. If in the
740
DR, PLUCKER ON A NEW GEOMETRY OF SPACE.
first case
in the second
LL' . MM' 7
NN'_ =*’
UU' . VV' 7
U'V' ~ ^
all rays thus determined constitute the linear complex, represented by
so — rff=k,
the axis of which is OZ.
If #=0, the linear complex is of a peculiar description, all its rays meet the same
right line, the axis OZ.
31. The results of [29] may be derived in a direct way. Let (rf, y', z') be any point
of space; according to the general equation (10) its corresponding plane with regard to
the complex
will be represented by
sq—rff—lc ... (24)
y'oc—ot?y=.k(z—z!) (25)
In putting tf=0, y'— 0, this equation shows that all planes corresponding to points of
the axis of rotation OZ are perpendicular to this axis (in the case of oblique coordinates
parallel to XY).
If the point fall within XY, we get by putting z'=0,
y'x—ody—kz\
consequently the corresponding plane passes through O. In denoting the angle which
it makes with the axis of rotation by X, we obtain
whence
cos X—
V yH +
y'*-\-ri2=Jci tan2k.
(26)
Hence we conclude,
Light lines parallel to and at an equal distance from the axis of the complex are met
under the same angle by planes corresponding to their points.
32. The following results are immediately derived from (26).
The plane jp corresponding to any given point P passes through OP, O being the
projection of P on OZ. Let the plane jp and the right line OM perpendicular to it in
O turn round the axis OZ, through an angle -, and denote them after turning by and
OM'. The projection of OP on OM' is a constant, and equal to p. So is the perpen-
dicular drawn from P to p’.
Again, k being given we may, by determining X, construct the plane corresponding to
a given point, and, conversely, by determining OP, construct the point corresponding to
a given plane.
DR. PLUCKER ON A NEW GEOMETRY OE SPACE. 741
The following theorem is the geometrical interpretation of the equation (25).
Draw through a point P its corresponding plane _p, and the plane XY perpendicular
to the axis of the complex meeting that axis in O. Let P be an arbitrary point ofy>,
and B' its projection on XY. The double area of the triangle POP' divided by P'P is
a constant, and equal to Jc.
33. In order to generalize, we may start from the equation
Ar+Bs+C-t-D<r+Eg-j-F(sg — ra)— 0 . (7),
and proceed in the following way. By replacing x, y, z by f, ?j, S- (see [16], note),
and omitting the accents, we immediately derive from equation (10),
|= C u — By — D w,
j? = — Ct -p Aw -}-Ew, (27)
£= Bt —Au—Fw,
F)t— Fu+Fv,
|, *i, £, S indicating any point, and t, u, v, w its corresponding plane. From the first
three of these equations results the equation
A| + Br, + C£ = — ( AD — BE + CF) w,
which, multiplied member by member by the fourth equation,
F)t— Em+Fw=S-,
and divided by Sw, furnishes the following relation,
(AH-By+Cz)(D^-E2+F^) =— (AD— BE+CF). . . . (28)
In a similar way we obtain
(C3 + E£ + D>))
Bt—Au—Fw
?
V
B3-D$ + F£
— C t -f- A u -f-
>1
u
>
ip
1
1
Cm — Bv — Dw
— £ t
= — (AD— BE+CF). }
34. In starting again from the equation (26),
sg — r<r=Jc,
and in supposing that there is a right line determined by means of the coordinates of
any two of its points (ad, y\ z') and (#", y", z") according to [31], its conjugate line will
be represented by the system of equations,
y’x — ady~Tc{z — z' ),
y"x-x"y=Jc(z—z"),
5 K
MDCCCLXY.
742
DR. PLUCKER ON A NEW GEOMETRY OF SPACE.
which, after eliminating successively y and x, may be replaced by the following ones :
x!,y,-^y,,=k[{^-x,)z-(x1,z'-x,z,%
In denoting the coordinates of the two conjugate lilies by
r0, s0, §0, <70, and r\ s°, g°, <r°,
the following relations are immediately obtained :
Whence
and
x"-x<
r0 — zii-.2i ’
?0— 2,l_s,
r°= k
r"z' — 7,'z"
.0 7. Z
t ~-/Cx"y'-x'y"
y»Sl-ylZ»
ff0 — z" — z' 5
s°= k-
-Jc
■ y z
y,o_,yo_go_(ro_(gogo- Wo)
(50?0— ^>o)(5°f0— r°G°) =k\
Not any two conjugate right lines intersect each other; if congruent they belong to
the complex.
35. A linear complex depends upon five constants, four of which fix in space the
position of its axis. In the case of the equations (23), this axis falling within an axis
of coordinates, there remains only one constant. The position of the axis of the com-
plex and its remaining constant may be determined by means of the five independent
constants of the general equation (7).
For that purpose we shall make use of the transformation of coordinates. If the
axes of coordinates be changed, the coordinates of a ray change at the same time, and
we get formulae analogous to the formulae in the case of ordinary coordinates, in order
to express the coordinates of one system by means of the coordinates in the other.
36. Let
x=rz+<>,
y=sz+( 7
be the equations of a ray referred to the system of coordinates ( x , y, z ). If referred to
another system ( x y\ z'), its coordinates will be replaced by new ones (r', s', q, </), but
their equations retain the same shape,
sWa'+g',
y=5'2'H-<7'.
DE. PLUCKEE ON A NEW GEOMETEY OE SPACE.
743
If the primitive system of coordinates be only displaced parallel to itself, the coordi-
nates of the new origin being (x°, y°, z°), we obtain
x’=x—x\ y'=y—y\ z'=z—z°;
and by substituting in the last equations,
x=r,z + (f' + x°— r'z ),
y=s'z+(<Tf+y0-s‘fz);
whence, by comparison with the primitive equations,
We have further
s=s,
g=4+a?—rz0, 1
<r=o'+y°-Sz°.)
sg—ra— (s'g' — rV) + x°s —y°r.
(30)
(31)
If x°=0, y°=0, and accordingly the origin move along OZ, the expression (sg—ra)
remains unaltered [29].
37. If OY and OX turn round OZ, forming in the new position OY', OX' the angles
a! and a with OX, we have
x=x' cos a-\-y' cos vi=rz -j-f,
y—x] sin a+y sin ot—sz-\-c ;
whence, on putting («'— a)=^,
, rsina' — s cos a! , . o sin — tr sin af
X— — ^ Z- f5 r— ,
sin £ 1 sin 3
y=—
r sin cc — s cos «
sin $
>sma— <r sin «
sind
We immediately derive from these equations of the ray in the new system (a/, y', z'),
whence
/ sin §=r sin cx! — s cos a',
g' sin $=g sin ex!— a cos a!,
— s sin S=r sin a — s cos a, I
— a sin §=g sin a — <r cos a, ]
r^r1 cos a-\-s' cos a', j
g=g' cos a-fV cos I
s=r' sin a-j-s' sin ex', j
c=g' sin sin a', j
(31*)
(32)
(sg— re) = (s'g' — rV) sin
5 k 2
and
(33)
744
DR. PLUCKER ON A NEW GEOMETRY OF SPACE.
If especially 3=-, the last four equations become
r=7J cos a — s' sin a, '
g=g' cos a— o’ sin a,
s=rf sin a+s' cos a,
• • (34)
and the expression
<r=g' sin cos a,
sg — r<r
will not be altered by the transformation of coordinates [29],
38. Again, let OX and OZ turn round OY ; let a! and a be the angles formed by
these axes in their new position, OX' and OZ', with OZ, and a'— «=$■. In the new
system of coordinates the primitive equations of the ray become
(z1 sin a -\-cd sin a!)=(z' cos cos a')r-{-g,
y'=(d cos cos «')s-f-c\
From the first of these equations we derive
a/(sin a ' —r cos a') = — 2'(sin a— r cos a'j+f,
whence
^ sin a — r cos a
sin a! — r cos a!
§ =
sin a — r cos oc
(35)
(36)
After replacing in the second equation of this number of by (r'z'-{-g'), we obtain
y=(cos a -l-r' cos a' )sz' sg1 cos a'),
whence
s' = (cos a + r' cosa')s,
<7 '=(r-]-sg' cos oi ;
and by eliminating r' and g' by means of (35) and (36),
j ’s sin ■&
sin «' — r cos a
(erg — nr) cos «' + c sin a!
sin a! — r cos a!
From (35)-(38) we derive
from (36) and (37),
s'p'—r’o'— (sp — r<r) cosct + <r siu “ •
? sin u' — r cos «' ’
sin S-.
(37)
(38)
(39)
(40)
DE. PLUCKER ON A NEW GEOMETRY OF SPACE.
745
On the supposition of rectangular axes of coordinates, the last equations become
r=
sin ct—r cos a
cos u + r sin a
cos a + r sin a
cos a + r sin ci
(sg — go-) sin a — <r cos a
cos a + r sin a
(41)
,, , , (so — r<r) cos a — o- sin i
£> — rff =— : •
cos a + r sin a
Ǥ
g — §
. . . . (42)
• • • • (43)
In order to pass from the first system of coordinates to the second, r, s, g, <r and
r\ s', g>', d are to be replaced by one another, while the sign of a is to be changed. Thus
we get the following formulae : —
sin ci -f- r1 cos a
i — 7 ’
cos a — r sin a
§ =
a =
cos ci — r sin a
V
cos ci — r sin ci
(s' g' — r'a') sin « + c' cos «
cos u—r1 sin «
(44)
( s'p 1 — rl<rl) cos a —
So — TG— i-a L
b cos« — r sm
<r sin a
a
(45)
39. The general equation of the linear complex
Ar+Bs+C + D<r+Eg> + F(sf — r<r)=0 . . (7)
becomes, if the origin is moved to any point (x°, y°, z°) . . . (30),
(A — Yy° — Ez°)r + (B + Fx° — D^°)s + (C + E#° + Dz°) -f Do-' + E^' + F(so — r<r) = 0.
If
D E — F
the primitive equation is not altered. Consequently the complex remains the same if
it be moved parallel to itself along a direction indicated by the last equations. We
obtain in denoting by g, tj, £, the angles which this direction makes with OX, OY, OZ,
COS 0 COS 7) COS £
~TT E T'
(46)
40. In order to get OZ congruent with a right line OM of the determined direction
and passing through O, we may in the first instance turn the system of coordinates
746
DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
round OZ in its primitive position through an angle a such that ZX in its new position
contains OM. Accordingly we obtain
whence
cos a =
cosg
sin £ ’
tan2 a=
1 — cos2 £ — cos2 £ cos2 >] E2
cos2 0 cos2 0 D2
By making use of the formulae (34), the equation of the complex (7) becomes
(A cos 05 -|- B sin a)r'—( A sin 05— B cos a )s'
+ (E cos 05 + D sin u)g' — (E sin 05 — D cos oo^o^ — C F — rV)=0,
and may be written thus,
AV+B's+C'+D'<7+F(s£-r<r)=0, (47)
in omitting the accents of the new coordinates and in putting
E cos 05+ D sin 05=0, ]
A'=(AD-BE)C-^, B'=(AD+BE)C-^,| (48)
D'=(D2 + E2)^, C'=C, F'=F. |
E ;
41. In order to give within ZX to OZ the required direction along OM, the formulae
(44) are to be used after having replaced a by £. Accordingly the equation (47) is
transposed into the following one,
A'(sin £+F cos £)— BV+C'(cos Z>— F sin CQ
+ D'((slf'— /</) sin ^+o-' cos £)+F((s'g>'— rV) cos a’ sin £) = 0,
and may be written thus,
AV+ B"s + C" + F"(sg—rc) = 0, (48*)
on omitting the accents of the coordinates and putting
D' cos £=F' sin
A"=(A'F-C'D')^,
B"= — B',
C"=(A'F'+A'D')^,
(49)
F"=(D'2+F2)C-^.
42. Finally, the origin may be moved within XY to a point the coordinates of which
are #° and Accordingly the equation of the complex, on replacing f and c r by g-\-x°
and <r+^°, becomes
(A" — F'y )r + (B" + F V)s + C" + F"(sf — nr) = 0,
DE. PLUCKER ON A NEW GEOMETRY OE SPACE.
747
and by putting
is reduced to
x°= —
B"
w
C"
(sg—r<r)= — 'jTf=k.
43. By successive substitution we obtain
& — — j?ii
C'F'+A'D'
— ~ D,2 + F'2
CF + (AD - BE) (D2 + E9)
~ (D2 + E2)2^ + F2
and finally, on observing that
2 B2
COS CC — J)2_J_ JJ2’
the symmetrical expression
AD-BE + CF
fC—— J)2 + E2 + p2 •
. . (50)
. . (51)
(52)
In order to replace OZ and OX by each other, we may make use of the formulae (41)
and (42) on putting a=^r. By means of the last of these formulae the equation of the
linear complex (51) is immediately transformed into the following one,
t r=Jcr • (53)
the constant h being the same as before.
Again, on interchanging OY and OX we get
%=ks (54)
44. If Jc become equal to zero the complex is of a peculiar description, all its rays
meet a fixed line. If the complex be represented by the general equation
A/-f-Bs-(-C-j-D(7-{-Eg-|-F(5g| — r<r)=0, . . . (7)
this peculiar case is indicated by the following condition,
AD-BE+CF=0 (55)
45. By eliminating from the general equation of the complex or, § and (s§ — r< t) by
means of the equations
cc—rz- bg,
y— sz-\- or,
sx—ry—s^—ra.
we get
(A-fE^~E^+(B+F^-D^>+(CH-D^+E^)=:0.
748
DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
If there exist a point (x, y, z) where all rays of the complex meet, this point will be
determined by means of the following three equations,
A— Fy— Es =0,j
B + F^-D2=0,i (56)
C+Eff+Dy=0.J
These three equations can subsist simultaneously only in the case where (55) is satisfied.
If this condition be satisfied, the locus of points, where all rays of the complex meet,
is a right line, the projections of which are represented by the last equations (56).
46. Such rays as belong to both linear complexes,
Q,z=zAr + Bs + C 4-D<r +Eg> +F(s§ —
0'=A !r + B's + C' + DV + E 'g -f F'(s? -r<r)= 0, { ‘
constitute a linear congruency of rays represented by the system of the two equations. In
order to determine the congruency each of the two complexes,
0=0, O'=0
may be replaced by any other represented by
O+^Q'=0, (58)
where arbitrary values are given to the coefficient (m.
In each of the two complexes by means of which the congruency is determined, there
is a plane corresponding to each point of space which contains all rays starting from that
point. Both planes corresponding to the same point intersect each other along a single
ray, belonging to both complexes, i. e. to the congruency. With regard to the congruency
one ray corresponds to a given point of space. The planes corresponding to the same
point, in all complexes, represented by (58) meet along a fixed line, the corresponding
ray of the congruency.
Conversely, there is in each of the complexes (58) a point corresponding to a given
plane in which all rays confined within the plane meet. By means of two such com-
plexes we get, within the given plane, two points ; the right line joining the two points
is the only ray of the plane common to both complexes, and therefore belonging to the
congruency. We call it the ray of the congruency corresponding to the given plane.
To each point, as well as to each plane, corresponds only one ray. There are not any
two rays of the congruency intersecting one onother, or, in other terms, confined within
the same plane.
47. Suppose that AB is any given right line, and A'B', A"B" its two conjugate with
regard to the complexes O, O'. Let C be any point of AB. Each ray starting from C,
if confined within the plane A'B'C belongs to O, if confined within A"B"C to O'. There-
fore the intersection of the two planes A'B'C, A"B"C, i. e. the right line starting from C
and meeting both conjugate, is the ray of the congruency which corresponds to the
point C. If C move along AB, all rays of the congruency obtained in that way are the
DR. PLtiCKER ON A NEW GEOMETRY OF SPACE.
749
rays of one generation of a hyperboloid , while the given right line AB and its two con-
jugate A'B', A"B" are rays of its other generation. In replacing O and Q! by other
complexes arbitrarily taken among the complexes (58), the conjugate will be replaced by
others, all intersected by the rays of the congruency starting from AB. Hence
The right- lines conjugate to a given one , with regard to all complexes intersecting one
another along a linear congruency , belong to one generation of a hyperboloid , while the
right lines of its second generation are rays of the congruency meeting the given line.
48. If a point move along a given right line of space, according to the last number,
its corresponding ray generally describes a hyperboloid. We may say that the same
hyperboloid is described by the ray which corresponds to a plane passing through the
given right line and turning round it. If the ray be the same in both cases, the point
where it meets the given line AB is a point of the surface, and the plane confining both
AB and the ray, the tangent plane in that point.
49. The hyperboloid generated by a ray of a linear congruency, the corresponding
point of which moves along AB, varies if this line turn round one of its points C. All
the new hyperboloids contain the ray which corresponds to C, but there is no other ray
common to any two of them. If AB describe a plane, by turning round C through an
angle sr, there will be one ray of a hyperboloid passing through any point of space. A
linear congruency therefore may be generated by a variable hyperboloid turning round
one of its rays.
In an analogous way, a linear complex may be generated by a revolving variable con-
gruency.
50. While in each of the two complexes O and O' there is a fixed line — the axis of the
complex around which its rays are symmetrically distributed — there is in a linear con-
gruency a characteristic section parallel to both axes of the complexes, and a characteristic
direction perpendicular to it.
The characteristic section, if conducted through the origin O, may be represented by
the equation
ax -\rby cz— 0.
The two right lines starting from O and parallel to the two axes of the complexes are
represented by the double equations,
x y z
D=E_ T
P__y__P_
D'— E,— F‘
These lines being confined within the section, we get in order to determine the con-
stants of its equation,
aD +JE +<F =0,
«D'-t-6E'+cF=0,
whence
MDCCCLXV.
(D'E— E'D)&+(D'F— F'D)c=0,
(D'E— E'D)a— (E'F— -F'E)<?=0.
5 L
750
DR. PLtTCKER ON A NEW GEOMETRY OE SPACE.
Accordingly the equation of the section becomes
(E'F — F'E)# — (D'F —E'B)y (D'E — E!B)z = 0,
and the double equation of the right line perpendicular to it,
x —y z
E'F — F'E D'F — F'D D'E— E'D * ' ’ *
(59)
(60)
51. By giving to OZ the characteristic direction, the two complexes (57) will be
represented by linear equations of the form
0=Ar +C 4-D<r +Eg> =0,1
Q'=AV H-B's-f O' +D'<r+ E'g = Oj
(61)
the origin and the direction of OX and OY, perpendicular to OZ, remaining arbitrary.
Again, OZ may be moved parallel to itself, and accordingly o and a replaced by (g +#0)
and ( G-\-y° ), x° and y° being the coordinates of the new origin. If especially
C+D/+Etf°=0,
C'+Dy+EV=0,
whence
B C'D-D'C
* ~ “D'E-E'D’
C'E-E'C .
y — D'E-E'D ’
by the mere disappearance of C and C' the equations of the two complexes become
O =Ar -j-Bs -j-Eg =0, j
Q'EEAV+B's+D'<r+E'e = 0.J
OZ in its new position is a completely determined right line, which may be called
the axis of the congruency. It is easily seen that it intersects at right angles the two axes
of rotation of the complexes Q and O', and consequently the axes of all complexes
represented by (58).
52. The planes corresponding in the two complexes (62) to a given point (x’, y\ z')
are represented by
(A -E z' >r+(B —~Dz' )y+(EF -{-By' )z=Ax' +B y', |
(A'-EV>+(B'-DV)y+(EV+Dy>=AV+B^'./ ‘
In order to express that both corresponding planes are the same, we obtain the fol-
lowing relations,
(A — Es') : (B —Hz') : (Ex' +Ey') : {Ax' +By')=l Q
(A'-EV) : (B'-DV) : (EIx'+E'y1) : (AV+B'y). J }
Since both planes pass through the given point, any two equations, hence derived, are
sufficient in order to determine the locus of points having, in both complexes, the same
corresponding plane. From any two of the following six equations where the accents
are omitted, the remaining four may be derived ;
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
751
(D'E-E'D>2-[(B'E-E'B)— (A'D-D'A)>- (A'B-B'A)=0, .
(B'D - D'I%2 + [(B'E - E'B) + (AD - D'A )~\ccy + ( A'E - E'A)^= 0,
(AD — D' A)y + (A'E — E' A)ar + (D'E — ED )yz =0,
(BD-D'B)y-(B'E-E'B)#-(D'E-ED).r2=0,
(A'B — B'A)y + (A'E — E'A)#2 — (B'E — E'B)y2= 0,
(A'B - B'A> - (AD - D'A)xz + (BD - DB>2= 0 *
(65)
(66)
(67)
(68)
(69)
(70)
53. According to the first two equations (65), (66), the locus in question is a system
of two right lines both intersecting OZ. These lines are confined within two planes
parallel to XY and determined by (65) ; their direction within these planes is given by
(66). We shall call them the “ directrices” and the characteristic section parallel to
both and equidistant from them, the central plane of the linear congruency. Both
“directrices” intersect at right angles the axis of the congruency, as the axes of all
complexes do.
54. We may distinguish two general classes of linear congruencies ; either both direc-
trices are real or both imaginary. In a particular case the two directrices are con-
gruent. Finally, one of the two directrices may pass at an infinite distance.
55. If the directrices are real, and the plane XY be conducted through one of them,
the following condition, A'B— B'A— 0 (71)
is derived from (65). In order to determine within XY the direction of that directrix,
we get from (67), by putting 2=0,
(A'D-D'A)y+(A'E-E'A>=0 (72^
There is among the infinite number of complexes containing the congruency, which
are represented by
12-f-jO«Q'=0,
one of a particular description. It is obtained if, starting from (62), we put
whence
A B .
(AD - D'A)* + (A'E - E'A)g = 0.
(73)
All rays of that complex, and therefore all rays of the congruency, meet within XY a
fixed right line, represented by (72), on replacing g and a by x and y. This line there-
fore is the axis of that complex, and one of the two directrices of the congruency. In
the same way it may be proved that likewise all rays of the congruency meet the other
directrix. Hence
All rays of a congruency meet its two directrices.
* We may observe that any equation which, like those above, is homogeneous with regard to (A'B— BA),
A'C — C'A) . . . will not be altered if the complexes 12 and 12' are replaced by any of the complexes (12+jul2').
752
DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
Accordingly, both directrices being real and known, we may immediately draw through
any given point the only corresponding ray of the congruency.
56. In that peculiar class of congruencies indicated by the condition
D'E— E'D = 0, (74)
one of the two directrices passes at an infinite distance. By putting simultaneously
A'B-B'A=0,
we get, in order to represent the only remaining directrix, now confined within XY, the
same equation as before (72). But among the complexes,
0+^=0,
there is, besides the complex (73), the axis of which is the directrix, another complex,
represented by DOf-D'Q=(AT)-DA)r+(BT>-DE>=0,
the rays of which are parallel to a given plane. Its equation may be transformed into
Ar+Bs=0; (75)
accordingly the equation of the plane becomes
Aa’+B^=0.
Hence in this peculiar case
All rays of the linear congruency meet the only directrix , and are parallel to a given plane.
57. From the last considerations we conclude that among the complexes intersecting
each other along a linear congruency, and represented by
O+^O'=0, (76)
there are in the general case two, of a peculiar description, all the rays of which meet
their axes. These axes, the directrices of the congruency, are two conjugate right lines
with regard to each of the complexes (76).
Generally there is only one ray of the congruency passing through a given point, as
there is only one ray confined within a given plane. But each of the two directrices
may be considered as the locus of points, from which start an infinite number of rays,
constituting a plane which passes through the other directrix. It may be likewise
regarded as enveloped by planes, confining each an infinite number of rays, which con-
verge towards a point of the other directrix.
58. We may represent any two complexes O, O' in any position whatever by equa-
tions depending only upon the position of their axes and their constants. Let A be
the shortest distance of the two axes from each other, and S- the angle between their
directions.
Suppose that OZ intersects at right angles the axes of both complexes. Let OX be
the axis of the first complex O, k its constant, OX perpendicular to XZ. The equa-
tion of the complex will be 7
1 <7= AT.
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
753
If the axis OY be turned round O till, in its new position OY', the angle Y'OX
becoming 9, the plane ZOY' passes through the axis of the second complex, the last
equation, by putting .
<7=<r sm 9,
r=r'-i-s'cos9,
assumes the following form,
o’ sin 9 = Jcr' + Jed cos 9.
The axis of the second complex O' meets OZ in a point O', O'O being A. O' may be
regarded as the origin of new coordinates, OY and OZ being replaced by OY" con-
gruent with the axis of O', and by O'X" perpendicular to ZY" ; then the second com-
plex O' will be represented by the equation
g"=£'s",
g" and s" being the new ray-coordinates and k' the constant of the complex. In order
to make O'X" parallel to OX', it is to be turned round O' till, in its new position O'X'",
the angle Y"'0'X" becomes 9. Accordingly, by putting
g"=g'"sin 9,
s"=r'"cos9+s'",
the equation of the complex is transformed into the following,
g'" sin 9=#V"' cos .
Finally, by displacing the origin O' into O, g'" becomes gIV+Ar'", whence
g'" sin 9=(&' cos 9+ A sin 9)r'"-|-&V.
On omitting the accents, both complexes O and Q', referred to the same axes of
coordinates OZ, OY', OX, the two last of which include an angle 9, are represented
by the following equations,
<rsin9=#r-4-/£ cos9.s, 1
l (77)
g sin 9=(#' cos 9+ A sin 9)r+&'s. j
59. In order to determine the directrices of the congruency represented by the system
of the last equations (77), the equations (65) and (66) may be transformed by putting
A =k, B=£cos9, D=— sin 9, E=0,
A'=&'cos9+ A sin9, B'=&', D'=0, E'= — sin 9
into those following,
0 =(z sin 9)2- [(&+£') cos 9+ A sin 9> sin 9+(Mf sin29-A£ sin 9- cos 9), . (78)
A fy\ 2 (k'—k) cos — A sin y k
754
DR. PLtjCKER ON A. NEW GEOMETRY OE SPACE.
On denoting the roots of these equations by z' sinS, z" sin $•, and (^j , (^j , we obtain
(k—k1) cos $ + A sin 3-
sin S'
4 M'+ [(A: — k1) cosS — A sin S]?
sin2 S
{z'-z'J
(y\ ( y\" (A‘ + #)cos5 — AsinS
ay\' fy\"\2 4^'+ [(A — A') e°s ^ — A sin •&]
*) " w ) ~
The roots of both equations are simultaneously either real, or imaginary, or congruent.
In the last case we have
(k—k') cosS — A sin$-=2v^ — kk/,
whence
(f)'-(5W4-
The central plane of the congruency is represented by
( k — k') cos S — A sin S
2 sin S
(SO)
In two peculiar cases this equation becomes
z—\ A,
either if
&=**■,
or, whatever may be if
k=U.
Hence the axes of any two complexes selected among those intersecting each other
along a given congruency are at equal distances from its central plane if their directions
are perpendicular to each other, or if the constants of both complexes are the same.
60. Without entering into a more detailed discussion of the last results we may
finally treat the inverse problem : a congruency being given by means of its two direc-
trices, to determine the complexes passing through it. On the supposition of rectangular
coordinates, the two directrices may be represented by the following systems of equations,
y—ax— 0, z=d,.
y-\-a%=0, z=—0.
These directrices are the axes of two complexes of a peculiar description, ranging among
the infinite number of complexes which intersect each other along the congruency.
The two complexes, if moved parallel to themselves till their axes fall within XY, are
represented by the equations
<7 — ag= 0,
<T -|-ff£ = 0,
DR. PLfiCKER OX A NEW GEOMETRY OF SPACE.
755
whence, in order to represent them in their primitive position, the following equations
are derived,
<7 — « + 0s — 0«r = 0,
<r-\-a§—0s—0ar= 0.
By adding the two equations, after having multiplied the second by an undetermined
coefficient p, the following equation results,
(1 -\-[a)<7— (1 — (1 — ^)0s— (1 -\-^)6ar— 0,
which, on putting
1=C=X.
becomes
a-Xag-\-X6s—6ar— 0 (81)
By varying A all complexes intersecting each other along the congruency are repre-
sented by this equation. Their axes are parallel to XY and meet OZ. According to
(19) and (52) we may immediately derive the direction of the axes and their constants.
The following way of proceeding leads us to the same results, giving besides the position
in space of their axes.
By turning OX and OY round OZ through an angle a, by means of the formula (34),
in which a is to be replaced by a, the last equation is transformed into the following one,
(cos u-\-Xa sin + (sin a — Xa cos co)£ + (X cos co -\-a sin u)6s' + (X sin u — a cos w)6r' = 0,
whence, by putting
we obtain
tan co=Xa,
(82)
(1 + tan2 co)a' -f- (X tan u — a)6r' + (X + a tan <y)0s' =0.
Finally, by displacing the system of coordinates parallel to itself in such a way that the
origin moves along OZ through z° , we get
(1+ tan2!y)(7,-|-(Xtan<y— a)6r'-\- (A+«tan^)0s'— (1-f- tan2<y)^V=0,
whence, by putting
there results
„ A + a tan co ,
*= T+taAT*
, A tan m — a . T .
O '■ : ““ I i j. 2 * JC-T •
I -f tan -to
(83)
(84)
The values of tan <y, z°, and Ic remain real if both directrices become imaginary. In
this case, XY always remaining the central plane of the congruency and OZ its axis, a,
0, and ^ are to be replaced by a s/ — 1, $\/ —1, If a be real, we may put
a= tan a,
756
DE. PLtj CKEE ON A NEW OEOMETEY OF SPACE.
2a being the angle between the directions of the two directrices, bisected by XZ.
Accordingly we get
y tan co
tan «’
(85)
>0 1 + tan2 « tan co
tan « 1 + tan2 co
„ sin co cos co
= 0-
sin « cos sc
. sin 2co
= 4 • 0 ,
sin ‘Jet ’
Jc—6
tan2 a — tan2 co
tan «(1 + tan2 co)
] sirr a cos^ co — sin‘ co cos^a
sin a cos a
^sin (a + co) sin (a — co)
sin a cos a
(86)
(87)
The expression of z° shows that the axis within the central plane is directed along
one of the two right lines bisecting, within this plane, the angle between the directions
of the two directrices. These two right lines, having a peculiar relation to the congru-
ency, may be called its second and third axis. The three axes, perpendicular to each
other, meet in the centre of the congruency.
In order to express the angle a by means of 2°, we get the following equation,
2°
sin 2cy= - sin 2a,
0
indicating two directions perpendicular to each other, and corresponding to any value
of 2°.
61. By replacing in the expression
0 tanw
sin « cos a 1 + tan2 w
tan a by v- , we obtain on omitting the accent of 2°,
z(f+x*)=
sin « cos cl
xy.
(88)
The axes of all complexes constituting the congruency are confined within the surface
represented by that equation. But this equation remaining unaltered if the axes OX
and OY are replaced by one another, it is evident that the same surface contained the
axes of two different series of complexes ; one of the two series constituting the given
congruency, while the other constitutes a strange one, obtained by turning the given
congruency round its axis through a right angle.
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
757
62. In representing any three linear complexes by
O =A r +Bs +C 4-Do- +E§ +E (sg— rc)=0,j
a,EEAV+B's+C,+D4+E'g+F(sg-rff)=0,i (89)
0"=A"r+Bs" + C"+ D"<r + E"g + F "(sf -r<r) = 0, J
the system of these three equations represents a linear configuration of rays. The com-
plexes may be replaced by any three selected among those represented by
O -J- /^O' -f- vO!1 = 0
on giving to [h and v any values whatever. By combining the three complexes O, O', O"
we get three congruencies, and accordingly three couples of directrices. Each ray of
the configuration, belonging simultaneously to the three congruencies, meets both direc-
trices of each couple. Hence in the general case the configuration is a hyperboloid ; its
rays constitute one of its generations , while the directrices of all congruencies passing
through it are right lines of its other generation. Any three directrices are sufficient in
order to determine the hyperboloid.
63. Let P and P', Q and Q', B and B' be the three couples of directrices, each couple
determining a central plane. The three central planes II, K, P meet in one point C,
which shall be called the centre of the configuration. The segment of any ray of a con-
gruency bounded by both directrices being bisected by the central plane, the three right
lines drawn through the centre C of the configuration to the three couples of directrices
are bisected in the centre; they maybe called diameters of the configuration.
Let, for instance, 7r and tt' be the extremities of that diameter, xCtt', which meets both
directrices P and P'. The ray of the congruency (O, O') passing through 7 r is parallel
to P', the ray passing through t1 parallel to P. Both planes p andyV, drawn through P
and P' parallel to the central plane n, each confining two right lines (one directrix and
the ray parallel to the other) which belong to the two generations of the hyperboloid,
touch that configuration, and the point where both right lines in each plane meet is the
point of contact.
Draw through the six directrices P and P', Q and Q', B and B' six planes p and p',
g and q', r and n3 parallel to the central planes H, K, P. The six planes thus obtained
constitute a paralellopiped circumscribed to the configuration, the three diameters of
which join each the points of contact within two opposite planes. The axes of the three
corresponding congruencies (O, O'), (O, O'), (O', O") are equal to the distance of the
three couples of opposite planes ; their centres are easily found.
64. The hyperboloid thus obtained is not changed if the complexes O, O', O" be
replaced by any three others taken among the complexes
G+p,Q'+»>Q"=0,
but the three congruencies vary, and their directrices and the three diameters of the
hyperboloid. The directrices may be either real or imaginary ; accordingly the three
mdccclxv. 5 M
758 DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
diameters either intersect the hyperboloid or do not meet it. In the intermediate case,
where both congruencies are congruent, the corresponding diameter falls within the
asymptotic cone of the surface.
65. Conversely, starting from the hyperboloid and any three of its diameters, we may
revert to the three corresponding congruencies and the series of complexes by means of
which these congruencies are determined. If especially the three diameters are the
axes of the hyperboloid, the axes of the three congruencies meet in the same point, the
centre of the surface, and are directed along its axes.
There is a double way of reverting from a given hyperboloid to the congruencies, and
further on to the complexes. The right lines constituting each of its two generations
may be considered as its rays, while the right lines of its other generation will be found
to be the directrices of the congruencies passing through the surface.
66. It might be desirable to support in the analytical way the geometrical results
explained in the last numbers. For that purpose we may select in order to determine
the configuration, three complexes of that peculiar description where all rays meet the
axis. Accordingly the axes of the three complexes O, O', Q" are three of the six direc-
trices, P, Q, E for instance, confined within the planes j?, q, r. In assuming these
planes as planes of coordinates XY, XZ, YZ, the three complexes, constituting the con-
figuration, are represented by equations of the following form,
O =C +Do- -f-Eg>=0, j
Q'<;=B's +DV +F (sq — r<r)=0, l (90)
O" =A"r+Wq + F"(s§ - r<r) = 0. j
In order to represent by means of a single equation between x, y, z a configuration
determined by means of three equations between ray-coordinates, these coordinates are
to be eliminated by means of the following two equations,
x=rz-\-q,
y=sz+o ,
to which the third derived one,
sx—ry=sq—n t,
may be added. In our case we may at first eliminate sg— r<r, whence
(B' + Fx')s-F'yr +D'<r = 0,
(A" - F"y)r + Y"xs + E"§ = 0 ,
and after that § and <7,
E zr + D;ss = C + Dy + Ear,
(B' +Far -D'z)s-¥'yr +D'y =0,
(A" - F"y — Wz)r + F'^s + E"^= 0 .
DE. PLUCKEE ON A NEW GEOMETER OE SPACE.
759
Finally, by putting the values of r and s taken from the last two equations into the
first one, we obtain
{(B' +Yx -D'*)E"-F'Ify}Ea*
+ { ( A" — Y'y — WzJD' — E"F'^ } Dyz
-}- { ( A" — F"?/ — F'z) (B' + Y'x — D'z) + F'F"xy } (C + 1>/ + E#) =0,
which, by the disappearance of terms of the third order, becomes
A"B'C+A,,(B'E+CF)^+B,(A"D-CF")3/-C(A"D'+E"B'>'
+ A'T'Etf2— B'F"D^2+ CE'TO
+ (A"FD-B,F,E)^-(A"D'E+CE"F)^ I - * (91)
+(CF"D'-B'E"D)y2=0. j
After dividing by A"B'C and replacing
E 3) IP _F E" F
C’ C5 B'’ B'’ A"’ A"
by I, ?i, £', l', 71", the last equation assumes the following symmetrical form,
+1 fit'+wy+w** | (92)
+(^+iv')^+(r?"+r)«+w+>/'?v=o.|
In order to represent the configuration this equation replaces the three equations (90),
which may be written thus,
vr+!g — 1 = 0,
£'<r-i'(s£-rff)-l=0,l (93)
?e-A*s-n)+ 1=0- j
It shows that the configuration is a hyperboloid touching the three planes XY, XZ,
YZ. The rays within these planes are represented by
2=0, lx +7iy =1,1
y= 0, r*+r*=i,| (94)
#=0, >/ty+£"2=l,j
the directrices within them by
2=0, g'jF+V'y =1,1
y= 0, gar +$"*=1,1 : (95)
*=0, ny+?z= 1.1
The points of contact, being within each plane the intersection of the ray and the
directrix, are easily obtained.
The rays within the three planes of coordinates which form one edge of a circum-
scribed parallelopiped meet the directrices within the planes forming the opposite edge.
5 m 2
760
DE. PLUCKEE ON A NEW GrEOMETEY OF SPACE.
II. — On Complexes of Luminous Rays within Biaxal Crystals.
1. A single ray of light when meeting the surface of a doubly refracting crystal is
divided into two rays determined by means of their four coordinates, r, s, g, a. All inci-
dent rays constituting a configuration, especially all rays starting from a luminous point
and forming a conical surface, constitute within the crystal a new configuration, repre-
sented by the system of three equations between ray-coordinates. All incident rays
constituting a congruency, emanating, for instance, in all directions from a luminous
point, constitute within the crystal, after refraction, another congruency. Finally, a
complex of incident rays, all rays, for instance, emanating in all directions from every
point of a luminous curve, constitute within the crystal another complex of refracted
rays. The congruency of refracted rays is represented by two, the complex by a single
equation between ray-coordinates.
2. But before entering into the discussions indicated by the foregoing remarks, a
short digression on double refraction might be desirable.
A biaxal crystal being cut along any plane whatever, we may suppose that this plane
is congruent with xy , and that the point where an incident ray meets it is the origin of
coordinates O. Let /n x
x=pz, y=qz (1)
be the equations of the incident ray, whence
(2)
P 9
the equation of the plane of incidence. In the moment of Incidence the front of the
corresponding elementary wave, perpendicular to the ray, will be represented by
z+qy+px = 0 (3)
After the front of the wave has moved in air through the unit of distance, its equation
becomes , ...
z+qy+px=w (4)
on putting
At this moment the front of the wave intersects xy along a right line, which we may
denote by HR, the equation of which is
qy+px=w (5)
If the optical density of the surrounding medium increases, the value of w decreases
in the same ratio.
3. Around the point O, where the incident ray meets the section of the crystal, let
the wave-surface be described as it is at that moment when the front of the elementary
wave intersects xy along RR. The position of the axes of elasticity of the crystallized
medium being known with regard to the axes of coordinates, the equation of the wave-
surface only depends upon three constants a, #, c, which are to be referred to the same
DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
761
unit as w. If both systems of axes are congruent, the wave-surface is represented by
the well-kndwn equation
(«V+%2+cVX^+^+^)-[«2(^+c>2+^«2+c2)/+^K+J2K]+aW=0’ • (6)
which, for simplicity, may be written thus,
0=0.
4. The wave-surface is intimately connected with three ellipsoids, the equations of
which are 2 2 2
^2 +£2 =1j (?)
«V+5y+cV= 1, (8)
2^
h +£ +r* =1 (9)
By means of the first and the second ellipsoid the wave-surface may be obtained most
easily. The third ellipsoid has been introduced by myself on account of the following
remarkable property. With regard to this ellipsoid the wave-surface is its own polar
surface, i. e. the polar plane of any point of the surface touches it in another point, and
vice versd, the pole of any plane tangent to the surface is one of its points.
The wave-surface and the three ellipsoids depend upon the same constants. When
the crystal turns around the point of incidence O, both the surface and the three ellip-
soids simultaneously turn with it. In the new position their equations involve three
new constants, indicating the position of the axes of elasticity with regard to the axes
of coordinates. Now the wave-surface may be represented by
O'=0,
and the third ellipsoid in the corresponding position by
A#2+B#;y+Oy2d-2D#z+2%;s+F;s2---l=E=0 (10)
From the six constants of this equation, which may be regarded as known, you may
derive the six constants of the wave-surface by determining both the direction and the
length of the axes of the third ellipsoid.
Within the plane xy , supposed to be any section whatever of the crystal, OX and
OY may be directed along the axes of the ellipse along which this plane is intersected
by the third ellipsoid. Accordingly the constant B disappears from the last equation.
Besides, if OZ be directed along that diameter of the ellipsoid which is conjugate to
the plane xy, and cease therefore, in the general case, to be perpendicular to it, both
constants D and E likewise disappear.
5. According to Huyghens’s principle, we obtain both rays into which an incident
ray is divided, when entering the crystal, by the following general construction. Con-
struct the two planes passing through the trace RR and tangent to the wave-surface
described within the crystal around the point of incidence O. Let H and H' be the
762
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
points of contact within these planes. The two right lines OH, OH' drawn through the
point of incidence O and the two points of contact H, H' will be the refracted rays.
By means of the theorem referred to in the last number I have replaced this con-
struction by the following one, much easier to manage. Construct with regard to the
third auxiliary ellipsoid E the polar line of the trace HR. This polar line, which may
be denoted by SS, meets the wave-surface within the crystal in the two points H and H',
OH and OH' being, as before, the two refracted rays.
The plane HOH', containing both refracted rays OH, OH', may be called the plane of
refraction. There are, generally speaking, four tangent planes passing through RR, as
there are four points where the wave-surface is intersected by SS. We get therefore
four rays, all confined within the plane of refraction, but two of them, not entering the
crystal, are foreign to the question.
6. The plane of refraction may be constructed solely by means of the third ellipsoid
E. The details of this construction depend upon the well-known different modes of
determining the polar line SS. On proceeding in this way we meet some remarkable
corollaries concerning double refraction *.
7. The poles of all planes passing through the trace RR, represented by
qy-fpx=w . .
(5),
are points of SS. All right lines passing through the point of incidence O and these
poles fall within the plane of refraction confining SS. These right lines may likewise
be regarded as diameters of the ellipsoid E conjugate to diametral planes passing
through the trace along which the surface of the crystal, i. e. the plane xy, is inter-
sected by the wave-front in its primitive position, the trace being parallel to RR and
represented by
Hence qy+px= 0 (11)
The plane of refraction is that diametral plane of the ellipsoid E, the conjugate dia-
meter of which is perpendicular to the plane of incidence in O.
* In concluding a former paper, “Discussion de la forme generale des ondes lumineuses” (Crelle’s Journal,
No. xix. pp. 1 & 91, Mai 1838), I gave the following construction: —
“ Construisez, par rapport a l’ellipsoide directeur, la ligne droite polaire (SS) de celle qui est perpendiculaire
au plan d’incidence en O'. Elle coupera la surface de l’onde, decrite autour du point 0, en deux points. Les
deux lignes droites qui vont du point 0 aboutir a ces points seront les deux rayons refractes ; tandis que les
deux plans, qui, contenant la perpendiculaire en 0' (RR), passent par ces deux m ernes points seront les fronts
des deux ondes planes correspondantes. Enfin il a ete demontre, dans ce qui precede, que les deux plans de
vibration sont ceux qu’on obtient en conduisant par les rayons lumineux (refractes) des plans perpendiculaires
aux fronts des ondes correspondantes.”
At the present occasion I resume the discussion, announced by myself twenty-six years ago, of a part of this
construction. More recently, in the eighteenth Legon of his valuable work, ‘ Theorie mathematique de l’Elasti-
cite’ (1852), M. Lam£ reproduces the curious relation between the wave-surface and the third ellipsoid. He
presents in the following Legon a remarkable theorem, “ which is one of those immediately derived from this
relation.” [8]
DE. PLTJCKEE ON A NEW GEOMETEY OF SPACE.
763
Accordingly the plane of refraction, conjugate to (6), is represented by the equation
dE dE
dxQ- dy$>’>
(12)
which may be expanded into the following one,
(Ax+By+T>z)q=(Bx+Cy+'Ez)p, (13)
or
{Aq— Bp)x-\-(¥>q— Cp)y+(Dq— Ej?)z=0* (14)
8. These equations remain unaltered if p and q vary in such a way that the ratio ^
remains the same, i. e. if the angle of incidence vary while the plane , of incidence
remains the same. The same equations do not contain w, the value of which depends
upon the density of the surrounding medium. Hence
All rays of light confined within the same plane of incidence, after being divided into
two by double refraction , are confined again within the same plane — the plane of refrac-
tion. This plane remains the same if the surrounding medium be changed.
9. The plane xy, i. e. the surface of the crystal, containing the trace (11), its conju-
gate diameter, the equations of which are
or
«-0
(15)
Atf+B.y+D^O, |
B#+Qy+E;z =0, j
(16)
is confined within the plane of refraction, whatever may be the incident ray. The same
may be proved analytically by observing that (12) is satisfied by means of the two equa-
tions (15). Hence
A ray of light of any direction whatever meeting the surface of a biaxal crystal in a
fixed point is so refracted that the plane containing both refracted rays passes through a
fixed right line (15).
* On representing any one of both refracted rays by the equations
x=rz, y=sz,
the last equation, written thus,
(A2-Bi>>+(B2-Cp)S.+(D?-Ep)=0, (1)
indicates a relation between the direction of the incident ray, determined by the constants p and q, and the
direction of the refracted one, determined by r and s.
This equation will not be altered if the incident ray, moved parallel to itself, meet the section of the crystal
in any point
x=?> y=r.
If r and s be regarded as variable, and <r being constant, the equation (1) represents the plane of refraction
corresponding to the incident ray
x=pz-\-§, y=qz+c,
and containing both refracted rays.
764
DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
If without the crystal the ‘plane of incidence turns round the perpendicular to the
section , within the crystal the plane of refraction simultaneously turns round the diameter
of the third ellipsoid conjugate to the section.
10. In order to construct the plane of refraction, we want to know another diameter
conjugate to any plane passing through the trace (11). In selecting among these planes
the wave-front itself in its primitive position, the plane of refraction will be obtained by
drawing a plane through both diameters conjugate to the section of the crystal and the
primitive wave-front.
The wave-front in its primitive position is represented by
px+qy+z= 0,
its conjugate diameter by the equations
rfB dE j
^ dz ^ I
[ (17)
dy ^ " dz ’ j
which, if expanded, become
Ax + By + Dz =p( Dx+ E y -j- F2), |
Dx-\-Oy-\-Dz = g{Dx-\-Dy-\-Dz).\
In order to prove in the analytical way that the diameter conjugate to the primitive
wave-front falls within the plane of refraction, it is sufficient to observe that, by elimi-
rfE
nating -gp- between the two equations (17), the equation of the plane of refraction (12)
is obtained.
11. If a ray of light meet the surface of a crystal in a given point, the third ellipsoid
remains invariably the same as long as the position of the crystal is not altered. There-
fore the diameter conjugate to the wave-front remaining likewise the same, whatever
may be the section of the crystal passing through the point of incidence, the plane of
refraction always passes through that fixed diameter. Again, if the incident ray, dis-
placed parallel to itself, meet the surface of the crystal in a new point, this new point of
incidence becomes the centre of the third ellipsoid, likewise displaced parallel to itself.
The diameter conjugate to the primitive wave-front, always passing through the point
of incidence, retains the same direction. We may finally observe that the surface of the
crystal, if a curved one, may be replaced for any incident ray by the plane tangent to it
in the point of incidence.
If a ray of light meet a biaxal crystal in a given point , whatever may be the surface
bounding the crystal and containing that point, the plane of refraction passes through a
fixed right line.
If a system of parallel rays meet the surface of a biaxal crystal , each ray of which
after double refraction is divided into two, there is within the crystal a fixed direction ,
not depending upon the shape of the surface , so that the directions of both refracted rays
DR. PLUCKER ON A NEW GEOMETRY OF SPACE.
765
into which any incident ray is divided , and that fixed direction , are confined within the
same plane.
12. By putting
Ey=Ey,
the equation of the plane of refraction becomes
(Aq—~Bp)x+ (B<?- Op>= 0,
which, after eliminating p and q, may be written thus,
(AE-DB>+(BE-DC)y=0 (19)
In this case the plane of refraction is perpendicular to xy and passes through OZ.
The plane of incidence perpendicular to xy, or its trace within this plane, is represented
by
I (20)
It is easily seen that this trace is perpendicular to the trace of that diametral plane
which, with regard to the ellipsoid E, is conjugate to OZ. Indeed this plane is repre-
sented by
“=»H-%+F*=0,
and its trace within xy by
Rr-f Ey=0.
Each ray within the plane of incidence (20) is divided by double refraction into two,
both confined within the same vertical plane of refraction. That is especially the case
with regard to the ray incident at right angles ; the corresponding plane of refraction,
represented by (19), contains the incident ray and both the refracted rays.
13. Besides the vertical ray, there is in each plane of incidence one ray confined with
both refracted rays within the same plane. After eliminating p and q between the
general equations of the planes of incidence and of refraction,
qx—py,
(Ax + By + ~Dz)q=(Bx +Cy+ E z)p,
the following equation is obtained,
B(y—x*)+(A-C)xy + (-Dy-Ex)z=0, (21)
representing a cone of the second degree, the locus of incident rays which are confined
within their corresponding planes of refraction. This cone passes through the vertical
OZ, and intersects xy within two right lines perpendicular to each other. These lines
are congruent with the two axes of the ellipse
Aa-2+2B^4-Oy2=l, (22)
along which the plane xy is intersected by the ellipsoid E. (That is instantly seen by
putting B=0 [4].) Hence both rays, grazing the surface of the crystal along the axes
of the ellipse (22), are confined with both corresponding refracted rays within the same
plane.
MDCCCLXY. 5 N
766
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
If especially the crystal be cut in such a way that xy become a circular section of the
ellipsoid E, each ray grazing the surface of the crystal will be contained within the cor-
responding plane of refraction. This plane therefore is easily obtained by means of the
trace of the plane of incidence and the diameter OZ' of the ellipsoid E conjugate to its
circular section xy.
14. In the preceding numbers the plane of refraction has been determined without
determining SS confined within it. This right line, passing through the infinitely distant
pole of xy, is parallel to the diameter OZ' conjugate to xy and represented by the equa-
tions (16), which by eliminating successively y and x may be replaced by the following
ones,
(B2— AC> + (BE— CD>=0,1
• (B2-AC)y+(BD-AE>=0.j [ }
The direction of SS being known, any one of its points, i. e. the pole of any plane passing
through RR, will be sufficient to construct it. If the plane be parallel to the diameter
just determined, its pole will fall within the plane xy, and may be also regarded as the
pole of RR, with regard to the ellipse (22) along which this plane is intersected by E.
The trace RR being represented by
qy-\-jpx=w,
where
the two lines, the equations of which are
(A^+By) ~ = 1,
(Bx+Cy) ^=1,
will meet in the pole mentioned. Hence, on denoting its coordinates by x° and y°,
By-Cp 1 ,
X ~ B2-AC w
PrAg.l. [
y B2— AC w J
(24)
Finally, the equations of SS thus obtained are
x—x° y—y° z
CD— BE=AE — BD B2— AC
(25)
In order to complete the construction of the two refracted rays, the points (M, M')
in which SS meets the wave-surface O within the crystal are to be joined with O by
means of two right lines OM and OM7.
15. If rays of every direction meet the crystal in O, the corresponding wave-fronts in
that moment when, within the crystal, the wave-surface O is formed, will envelope a
sphere,
DE. PLtiCKEE ON A NEW GEOMETEY OF SPACE.
767
the radius of which is equal to unity. The locus of poles of the wave-fronts, if taken
with regard to the ellipsoid E, is a new ellipsoid, which, referred to axes of coordinates
directed along the axes of all auxiliary ellipsoids, is represented by the equation
!2c2~^a262
= 1,
aV+%2+cV=aW
(26)
Its axes are obtained by multiplying the axes of the second auxiliary ellipsoid (8), to
which it is similar, by abc.
16. The new fourth auxiliary ellipsoid (26) is fitted to connect the constructions of
the refracted rays if, the section of the crystal remaining the same, the direction of the
incident rays vary. Indeed a right line (MM') drawn through any point Y of the fourth
ellipsoid (26) parallel to OZ', i. e. to the diameter conjugate to xy with regard to the
third ellipsoid E, meets the wave-surface O, within the crystal, in two points M and M'.
OM and OM' will be the two refracted rays corresponding to that incident ray which is
perpendicular to the plane conjugate to OY.
17. After this digression we resume our subject.
Let xy be the section of a biaxal crystal and OZ perpendicular to it. Let a ray of any
direction starting from any point of OZ meet the section of the crystal in a point the
coordinates of which are
Let
x-%, y—a.
x=pz+q, 1
y=qz-\-a J
(27)
be the equations of the incident ray.
obtain the following relation,
Let
P—t
q a-
In order to express that this ray meets OZ we
(28)
(29)
x=rz+g, 1
y=sz+<r ]
be the equations of any one of the two corresponding refracted rays. Let us finally
suppose that, without the crystal, z is negative, within it, positive. Accordingly in the
equations of the incident ray, positive values of z, in the equations of the refracted rays,
negative ones are to be rejected.
Again, let
0=0
be the general equation of the wave-surface, and
E=A^2+2B^-j-C/+2D^+2E^+F22-l=0
the equation of the third auxiliary ellipsoid ; the position of both being determined by
the position of the crystal with regard to the axes of coordinates.
5 n 2
768
DR. PLtiCKER ON A NEW GEOMETRY OF SPACE.
18. According to the footnote of [7], we have between the four constants j?, q, r, s, upon
which the direction of the incident and the refracted ray depends, the following relation,
(Aq-Bp)r+(Bq-Cj))s+(Dq-Ep)=0 (30)
By means of (28) this equation may be transformed into the following one,
(Ac — B%)r-\- (B<r — Q>)s + (D<r — E^>) = 0, (31)
and then represents a complex of refracted rays. As no supposition is made regarding
the position of the luminous point on OZ, the corresponding incident rays may start in
every direction from all its points. They ’constitute therefore a complex of rays emanating
from OZ, perpendicular to the section of the crystal, and considered as a luminous right
line. This complex of incident rays, after entering the crystal, passes into the complex
of double refracted rays represented by the last equation.
19. By admitting that OX and OY, within the section of the crystal, were directed
along the axes of the ellipse, along which xy is intersected by the ellipsoid E, the constant
B disappears from the equation of the complex, which then may be written thus,
(Ar+D)<r=(Cs+E)g> (32)
We have hitherto supposed OZ to be perpendicular to xy , and will continue to do
so for incident rays without the crystal ; but for the refracted rays entering it (the axes
OX, OY, perpendicular to each other, remaining the same) the direction of OZ may
be changed by replacing it by the diameter OZ' of the ellipsoid E, conjugate to xy. Then
the constants D and E likewise disappear, and the equation of the complex assumes the
most simple form,
Arc=Csg.
20. On denoting by a0 and b0 the two semiaxesof the ellipse along which xy is
intersected by the ellipsoid E, we get
A=-2> b=4-
ao K
We may suppose, too, that a0 falling within OX, is greater than bQ falling within OY,
a?—b 2
whence the square of the excentricity of the ellipse e\ becomes 0 2 0 •
ao
After having introduced the new constants, the last equation may be written in the
following ways,
(34)
sg — r<r
s
Besides, on observing that
f_£5
g p ’
blq
al P
(35)
(36)
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
769
In order to get a geometrical interpretation of these equations, let any refracted ray
of the complex be projected in the ordinary way on the three planes of coordinates XY,
XZ and YZ ; each axis of coordinates will be met by two of the three projections. The
intercepts on OZ' are j and^; on OY, <r and on OX, g and — - 1 cr. Hence
With regard to all rays of the complex , the two intercepts on each axis of coordinates
are in the same ratio.
For OZ', i. e. for the diameter of the ellipsoid E conjugate to the section of the
crystal, this ratio is the ratio of the squares of the axes of the ellipse within this plane.
For OY, i. e. for the shorter axis of this ellipse, it is equal to the square of its excentri-
city ; for OX the greater axis equal to
Finally, if any incident ray, without, he projected on the section xy of the crystal
along OZ, i. e. perpendicularly, and one of the two corresponding refracted rays, within
the crystal, along OZ', the projections thus obtained are the traces of the planes of inci-
dence and of refraction, - and - indicatin
g the trigonometrical tangents of the angles,
between the two traces and the greater axis of the ellipse within the section xy. The
ratio of the tangents is egual to the ratio of the squares of the axes of the ellipse.
21. In order to get a general idea of the distribution of the refracted rays constituting
the complex, we may determine first the cone formed by rays passing through any given
point within the crystal. If M he this point and x0, y0, z'0 its coordinates, the equations
xQ=rz’a+gf
y0—sz'0-\-tr,\
are to be combined with the equation of the complex, which, on putting
written thus,
sg=j3V<r
By eliminating g> and <r, we get
x0s — (32y0r = ( 1 — / 32)z'0rs
. . . (37)
~=i 3, may be
. . . (38)
. . . (39)
This equation shows that the locus of rays of the complex which pass through the point
M is a cone of the second degree. Its equation in ordinary coordinates x, y, z' (z1 being
referred to OZ') is
®«(y-yoX^-^)-^-^-^)=(i-W(*-*o)(y-y^ • • • (40)
From this equation we immediately derive that, whatever may be the position of M
within the crystal, the cone always contains three rays parallel to OX, OY, OZ', as well
as a fourth ray passing through the origin O. Besides, the cone depends upon the only
constant (3, the ratio of the two axes of the ellipse, here represented by
f! , £=1
«n ^ bl ’
(41)
along which xy is intersected by the third auxiliary ellipsoid E.
The equation (39), only depending upon the ratio of the constants x0 , y0, z0, shows
770
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
that the cone in question of double refracted rays is not at all altered if its centre moves
along a right line passing through the origin O.
22. In the peculiar case where M lies within the section of the crystal xy all corre-
sponding incident rays likewise meet in that same point, constituting the plane of inci-
dence passing through OZ, and represented by
y'x=a?y.
Here the cone of refracted rays degenerates into a system of two planes, which after
putting z'0=0., are represented by
z'=0, I
L (42)
Xo{y-yo)=PX{x-oco)'\
The second of these equations represents the plane of refraction corresponding to the
plane of incidence *.
23. If M fall within one of both the other planes of coordinates XZ and YZ, the cone
of double refracted rays likewise degenerates into two planes.
24. Either by putting s' = 0 in (40), or, after having eliminated r and s between the three
equations (37) and (38), byreplacing the remaining variables § and a by x and y, we obtain
y0x-p2x°y=(l-(3*)xy (43)
This equation represents, within xy, the trace of the cone of refracted rays which meet
in M. It is an equilateral hyperbola, having its asymptotes parallel to OX and OY, and
passing through the projection of M. The coordinates of its centre are
whence
V— l— /32 x~
y_ _JL Vo,
X /32 Xq
Pa*b
1-/32’
As the equation (43) does not involve the constant z'0, we conclude that
The cone of double refracted rays continually changes if its centre be moved along a
right line parallel to OZ', but its trace within the section of the crystal always remains
the same hyperbola.
25. Secondly, we may determine the curve enveloped by refracted rays confined
within any given plane. If the plane be
tx-\- uy-\-vz-\-w=0.
* In the present researches, the auxiliary ellipsoid E, which may he considered as described round any point
of the section of the crystal, as well as the wave-surface itself, has no other signification than to indicate by
its constants the molecular constitution of the crystal so far as the transmission of luminous vibrations is con-
cerned. Our equations only containing the ratio of these constants, the ellipsoid E and its elliptical trace (41)
may be supposed here to have any dimensions whatever.
The last equation (42) represents the plane of refraction as it represents its trace within xy. It likewise
represents, if the point M falls within the circumference of the ellipse (41), the normal to that curve in the
point M. Hence is derived an elegant construction of the plane of refraction.
If within xy round any point of incidence as centre the ellipse (41) be described, the traces of the planes,
both of incidence and of refraction, are such two diameters of that ellipse, the second of which is parallel to the
normal to it at the point where the first intersects it.
DE. PLUCKEE ON A NEW GEOMETEY OE SPACE.
771
the equation of this curve will result from the combination of the equation of the
complex
sg=@2rcr (38)
with the two equations
tr-\-us-\-v =0,
tg-\-ua-\-w=b,
expressing that a ray ( r , s, g, <r) falls within that plane. By eliminating r and g, we
obtain
ws— (32v<r-\-(l — /32)us(r=0, (44)
^ and ^ ^ being the coordinates of the projection, within xy', of the refracted ray.
The projection envelopes an hyperbola ; so does the ray itself within the given plane.
The last equation (44) does not contain t, and therefore will not be altered if the given
plane turns round its trace within YZ', represented by
uy+vz' +w= 0 (45)
Hence it follows that the projections of all refracted rays which meet that trace are
tangents to the same hyperbola (44), the asymptotes of which are parallel to OY and
OZ', and which especially is touched by the trace itself, with regard to which
W <7 W
U S V
The refracted rays themselves are tangents to a hyperbolic cylinder having as base the
hyperbola (44) and OX as axis.
26. In order to particularize, let us, in the first instance, suppose that the trace (45)
is parallel to OZ' and intersects OY in any point Q, OQ being equal to Then
v being equal to zero, the equation (44) becomes
(w+(l-/3>)s=0,
indicating that the hyperbola of the general case degenerates into two points, falling
within OY, one at an infinite distance, while the distance of the other (Q') from O is
OQ'=,= -tz«- = i^OQ.
(46)
Accordingly the hyperbolic cylinder degenerates into two right lines, met by all
refracted rays. One of the two lines within the plane xy along which the crystal is cut
is parallel to OX, and intersects OY in Q ', the other is infinitely distant. Hence all
rays within a plane intersecting xz' along a trace (QZ'0) parallel to OZ' are divided into
two sets. The rays of one set being parallel to the plane xy may be here omitted. The
rays of the other set meet in a fixed point of that same plane along which the crystal is
cut. If the plane turns round its trace QZ„ the fixed point moves, within xy, parallel
to OX, describing a right line Q'X0. Each ray meeting both right lines QZ'0 and Q'X0
is a ray of the complex.
DE. PLUCKEE ON A NEW GEOMETEY OE SPACE.
27. If, in the second instance, the trace (45) is parallel to OY and intersects OZ'
in E, OE being equal to the equation (44) becomes
ws=j32w,
representing a point of OZ', the distance of which from O is
OE'=-j = -i2“ = pOE. (47)
The hyperbolic cylinder therefore degenerates into a right line (EX0) within xz'
parallel to OX and passing through E'. Hence
All refracted rays of the complex confined within a plane intersecting yz' along a trace
(EY0) parallel to OY converge into a fixed point of the plane xz'. If the plane turns
round its trace, that point describes, within xz', a right line EX0 parallel to OX. Each
ray meeting both lines EY0 and E'X0 is a ray of the complex.
28. The axes of coordinates OX and OY may be interchanged by writing a0 instead
of b0, and reciprocally. Then we get analogous results if, instead of traces within YZ',
we consider traces within XZ'. Especially we may immediately conclude from the last
equation "written thus,
^.OE'=«;-.OE, (48)
that the relation between the two right lines E'X0 and EY0 is a mutual one.
29. All rays intersecting two fixed right lines constitute a linear congruency , the
fixed right lines being its directrices (Sect. I., 55). Consequently the complex of
refracted rays may be generated in three different ways by a variable linear congruency.
In each case the two directrices of the congruency move parallel to any two of the three
axes of coordinates OX, OY, OZ', intersecting the third axis in two points, the distances
of which from O are in a given ratio.
30. Hitherto we have supposed that the plane xy is any section whatever of the
crystal. Let us now, in particularizing again, admit that the crystal is cut along one of
the two circular sections of the third auxiliary ellipsoid E, then represented by
A(x2+y2)+Fz2=l;
/3 being equal to unity, the equation of the complex becomes
ra—sg (49)
In this peculiar case therefore all rays of the complex meet the diameter OZ', conju-
gate with regard to E to its circular section xy. Hence all refracted rays of the com-
plex intersect OZ' as all corresponding incident rays start from OZ.
Both the diameter of the third auxiliary ellipsoid E perpendicular to its circular section
xy, and its diameter conjugate to that section, fall within a principal section of the ellip-
soid containing its greatest and least axis, and consequently also its two optic axes. The
rectangular axes of coordinates OX and OY may, without changing the equation of the
complex, turn round O within the section xy. If one of them, OX for instance, become
DE. PLUCKEE ON A NEW GEOMETEY OF SPACE.
773
the vertical projection of OZ', the plane xz! is a principal plane of the ellipsoid E, con-
taining the two optic axes, and OY the mean axis of the ellipsoid E.
31. If the plane xy is a principal section of the third auxiliary ellipsoid E (and there-
fore of all auxiliary ellipsoids), the axis OZ', becoming perpendicular to xy, is congruent
with OZ. Then the equation of the ellipsoid E, referred to rectangular coordinates,
becomes
,;2 w2 ,2
i-jjL. i_— = 1
bc'ac'ab ’
and may be written thus,
ax'2 -f- by 2 cz2 = abc.
Hence the equation of the complex is
arc=bsg (50)
If the crystal be turned round OY through an angle %, we get, after replacing x and z
by
x cos a, — z sm a,
x sin k-\-z cos a,
the following equation of the ellipsoid E,
(a cos2 a-\-c sin2 ot)x2-\-by1— 2(a— c) sin a cos a . xz-j-(a sin2 a + c cos2 u)z2=abc. . (51)
The axes of the elliptic trace within xy being always directed along OY and OX, the
equation of the complex assumes the form of the equation (32), which, after putting
E=0 and
A : C : D = (« cos2 a — c sin2 a) : b : — {ci— c) sin a cos a,
passes into the following one,
(a cos2 a — c sin2 u)rc—bsg—(a—c) sin a cos a . <r=0 (52)
32. The equations (51) and (52) of the last number belong to the case in which one
of the three axes of elasticity, OY, falls within the section of the crystal. The two
remaining axes of elasticity are confined within the plane XZ, where one of them, corre-
sponding to C, makes with OZ an angle a, this angle being counted towards OX.
The two equations may be regarded as representing the general case of uniaxal crystals
cut along any plane whatever. Indeed let OC be the single optic axis making with the
normal to the section xy of the crystal any angle a. Draw through OC the plane xz
perpendicular to xy, and OY perpendicular to that plane. The rectangular system of
coordinates being thus determined, the equations (51) and (52), after having replaced
c by a, will belong to uniaxal crystals.
33. If the optic axis of an uniaxal crystal falls within the section xy, the equation of
the complex, on putting a=±7r, becomes
crc—as§.
In the case of uniaxal crystals, each plane passing through the optic axis may be
regarded as a principal section of the ellipsoid E. Therefore the equation of the com-
mdccclxv. 5 o
774
DE. PLUCKEE ON A NEW GEOMETER OE SPACE.
plex assumes the form of the equation (50); the form of the tWo equations being the
same as in the general case, where the direction of the third axis is obliqtie to xy.
If in the case of uniaxal crystals the circular section of E is congrilelit with the sec-
tion xy of the crystal, we get in order to represent the complex of double refracted
rays, on putting a=0, the following equation,
indicating that the plane of refraction is congruent with the plane of incidence, or, in
other terms, that both the' ordinary and the extraordinary ray into which any incident
ray, starting from OZ, is divided by double refraction, likewise meet OZ.
34. The preceding fragmentary researches on double refraction — only calculated to
present a new and curious instance of a complex — may be concluded by a last remark.
All the results we have hitherto obtained, especially the determination of the com-
plex of double refracted rays, only depend, 1st, upon the direction of the diameter of the
ellipsoid E conjugate to the section of the crystal; 2ndly, upon the ratio of the axes of
the elliptical trace along which the same ellipsoid meets that section. Here, therefore,
the third auxiliary ellipsoid E, 21721 2 7,
ax oy ~\“Cz — aoc^
may be replaced by the following one,
ax2-{-hy2-\-c'z2=l,
which is similar to it. It is immediately seen that, along the different directions, the
reciprocal values of optical elasticity within the crystal are indicated by the radii vec-
tor es of the new ellipsoid, as the squares of these values are represented by the radii
vectores of the second auxiliary ellipsoid,
fflV + b2y2 + c V = 1 .
Additional Note.
Deceived December 11, 1865.
I. Coordinates of a right line.
1. A right line, if considered as an axis round which a plane revolves, is determined
by any two positions of the revolving plane ; analytically, by means of two groups of
plane-coordinates. If considered as a geometrical locus, described by a point, it is
determined by any two positions of the moving point ; analytically, by means of two
groups of point-coordinates.
Let the plane- and point-coordinates
ST '57 ST
t U V
— , —5 —5
WWW
DR. PLUCKEE ON A NEW GEOMETRY OF SPACE.
775
be such that
tx-\-wy-\-vz-\-wm= 0, . . (1)
which equation, if geometrically interpreted, indicates that each point ^ falls
within each plane or, which is the same, that each plane passes
through each point ( — , X, — ) . I called such coordinates “ associated plane- and point-
coordinates”*, and here we shall make use of that denomination. By two couples of
associated either plane- or point-coordinates,
t u v f! u' v'
— ’ — ’ — ’ — i’ — /’
WWW WWW
x y z x' y' z'
— , , — | 5 — —5
UT '57 •07 ® W
the same right line is determined.
We may employ homogeneous instead of ordinary equationsf ; accordingly each group
of three coordinates is replaced by a group of four :
t , u, v, w, vl, v', uo\
0C, y, Z, nr, x', y, z', W!.
2. Both planes ( t , u, v, w) and (ff, u\ v', w'), represented in point-coordinates by the
equations
tx -\-uy -\-vz +wc7 =0,
t'x -j-ury-\-v'z-{-w!vj=0,
are arbitrarily chosen amongst those passing through the right line, and may be replaced
by any two others, the equations of which have the form
(t-\-yrf)x-\-(ur\- i*u')y4- (v-\-/jijv')z^-(w-\-[Jjw')vi ■ = 0,
where p denotes any arbitrary coefficient. But the position of the right line with
regard to the axes of coordinates OX, OY, OZ is not characteristically connected
with such a plane, except in the case where the plane itself has a peculiar relation to
the axes. There are four such cases : the plane may either pass through the origin, or
project the right line on the three planes of coordinates. Accordingly, in putting
w+(jt,w'= 0, v-\-pv'=0, w+|tW=0, t-\-yjtf= 0,
the last equation successively becomes
(tw1— t'w)x-\-(uw' — u'w)y + (vw' — v'w)z = 0 , ^
(tv' —t'v )x-j-(uv' —u'v )y—(vw'—v'w)m =0,
( tu ' —t'u)x—(uv' —u'v )z—(uw'—u'w)&= 0,
— -( tu' —t'u)y—(tv ' —t'v )z—(tw'—t'w)m= 0.
* Geometrie des Raumes, No. 5.
t I first introduced homogeneous equatipns into analytical geometry, Ckeele’s Journal, v. p. 1, 1830.
5 o 2
(2)
776
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
Any two of the four planes represented by these equations are sufficient to fix the posi-
tion of the right line. They contain five constants, which by division may be reduced
to four, the necessary number upon which the line depends. Besides the five constants
in the two equations we meet a sixth one in both remaining equations. But the right
line being determined by the former five, the sixth ought to be a function of them. The
equation of condition, connecting the six constants, may, for instance, be obtained by
adding the three last equations, after having multiplied the first of them by — (tv! — tv),
the second by (tv' — t'v), and the third by — (uv1 — u'v). Thus we obtain
( tu'—t'u)(vw'—v'w)—(tv'—t'v)(uw'—u'w)-\-(uv'—u'v)(tw'—t,w)=0 . . . . (3)
The following six constants, taken with an arbitrary sign,
+(uv'—u'v), + (tv'—t'v), +(tu'—t'u), + (tw'—t'w), +(uw'—u'w), +(vw'— v'w),
may be regarded as the six coordinates of the right line .
3. In quite a similar manner, when in order to fix the position of the right line
we replace the two planes by the two points ( x , y , z, m) and (ct, y', z ', m'), we get the
following equations in plane coordinates,
(xtx1 — x'rn)t -{-(ysr1 — y'xn)u-{-(z^' — z!vs)v =0,
(xz1 -x'z )t -\-(yz' —y'z )u-(zJ -z'u)w= 0,
{xyl -othy )t —( yz ' —y'z )v -(yvs'-y'^w— 0,
. — (xy' —x'y )u — (xz! —x'z )v — (xm1— x'&)w=0,
representing four points, the first of which is at an infinite distance on the right line of
which the position is to be determined, while the three others are the points in which
that line meets the three planes of coordinates. Accordingly we may likewise regard
the six constants of the last four equations, taken with an arbitrary sign,
-\-(xts’ — x'&), + (y&' — yV), +(2ot' — z'&), ±(yz' — y'z), ^(xz1 — x'z), -{-(xy' — oty),
as the six coordinates of the right line. These six coordinates are connected by the
following equation of condition:
(xy'-ody)(zv’—z'v!)—(xz'-cJz)(yv'-y'™)+(yz'-tfz)(xv'—riTS)=<). . . (5)
4. In denoting the distance of the right line from the origin of coordinates by \ the
angles with it makes with the three axes OX, OY, OZ by a, (3, y, and the angles which
the normal to the plane passing through it and the origin makes with the same axes
by X, g>, v, the following relations are obtained :
I. (uv1 —u'v ) : — (tv1 —t'v ) : (tv! —t'u) : ( tw' — Hw ) : (uw'—v!w) : (W— v'w)
II. —(xtz'—x'ts) : (yJ—y'm) : (zn'—z'n) : (yz1 —y'z) : —(xz! —x’z) : (xy'—ody)
III. = cos a : cos/3 : cosy : hcosX : ticosy, : Scosv.
5. Hence we conclude that
cos (3, cos y, § cos x, 5 cos p, c> cos v
cos a,
DE. PLtJCKEE ON A NEW GEOMETEY OE SPACE.
777
may likewise be regarded as line-coordinates. Here the equation of condition between
the six coordinates becomes
cos a cos X -J- cos j3 cos cos y cos v=0,
which, added to the two following ones,
cos2a+ cos2]3-f- cos2 y=l,
cos2 X cos2jU/+ cos2v = l,
reduces to four the number of constants upon which the position of the line depends.
6. The two sets of ratios I. and II. retain the same generality after putting w—w' — + 1,
ot = gt'= + 1. If we suppose, again, that both planes and both points, by which the line is
determined, are coincident, we get, choosing the under signs, two new sets of equal ratios,
IV. —{udv—vdu) : —(tdv—vdt) : ( tdu—udt ) : dt : du : dv
V. = dx : dy . dz : (ydz— zdy) : — {xdz— zdx) : {xdy— ydx).
Thus we obtain two systems of differential coordinates, dx , dy , dz indicating the direction
of the line, dt , du , dv the direction of the normal to the plane passing through it and
the origin of coordinates. We may regard x, y, z, t, u, v as functions of time.
7. We can represent the direction of a force by the right line, and its intensity by
the distance of the two points by which the position of the line is fixed. In denominating
the projections of the force on OX, OY, OZ by X, Y, Z, and the projections of its
moment with regard to the origin on YZ, XZ, XY by L, M, N, we obtain the following
new set of equal ratios :
VI. =X : Y : Z : L : M : N.
Therefore X, Y, Z, L, M, N may also be considered as six line-coordinates. The equa-
tion of condition between them becomes
XL+YM+ZN=0 (6)
8. The six coordinates of each system range into two groups of three, to each
coordinate of one group corresponds one of the other. By exchanging the three axes of
coordinates, the three couples of corresponding coordinates are exchanged, both groups
remaining the same.
We may, in order to pass from the six coordinates of a right line to its five absolute
coordinates, divide any five of them by the sixth. Here we meet two cases, in dividing
either by a coordinate of the first or the second group.
9. Let us divide the first two and the three last terms of the ratios I. by the third
(tu1 — t'u). In putting
uv' — v!v tv 1 — t'v tu! — t'w uw' — u'w vw' — v'w
tv!— t'u tu' — t'u tu' — t'u <7’ tu! —t'u tu! — t'u Yh
where, according to the equation of condition (3),
n=ra—sg,
778
DE. PLUCKER ON A NEW GEOMETRY OE SPACE.
p, s, ( — <r), §, and 7i will be the Jive absolute coordinates of the right line. The last
of the four equations (2), representing the planes projecting the right line on the planes
XZ and YZ, as well as the projections themselves, may now be written thus,
x= rz-\-g,
y=sz+a,
r and s being the trigonometrical tangents of the angles made by the two projections
with the axis OZ, % and <r the segments intercepted by them on the axes OX and OY,
Again, let us divide the first five terms of the set of ratios II. by the sixth {pcj — x'y).
In putting
xvr — xts yts' — y’z? zw — zts y
I r —— ~~~ 7 T — 7T, ~ ~1 / ' — C?
xy' — ary ’ xy — xy xy — xy ^
yz ' — y'z xz' — x'z
xy1 — x'y xy1 — x'y &
where, according to the equation of condition (5),
2>, q, ( — «), 7r, and ^ will be the Jive new coordinates. We meet four of them in the
last two of the four equations (4), representing the two points where the planes XZ and
YZ are intersected by the right line. These equations assume the following form,
t =pv-\-7 rw,
u=qv-\-xw ,
and may, in denoting the coordinates of the points within their planes by xy, zy, and yx, zx,
be written thus,
(vyt+z9v+w= 0,
yxu+%jv ’±w= 0 ;
whence
We may add to the former six sets of equal ratios the two following:
VII. = r : 8 : 1 (—a) : q(==,r<r—,sg).
VIII. : 7 r : XJ=(px — q-rr) : jy : q : 1.
10. We have thus obtained eight different systems of line-coordinates, the coordinates
being the six terms of each of the eight sets of equal ratios I. to VIII. In changing the
position of the origin and the direction of the axes of coordinates, the coordinates of
each system are changed. But I do not here transcribe the formulae of transformation
of line-coordinates, observing only that these formulae may be immediately transferred
from one system to any other.
DE. PLUCKER ON A NEW GEOMETRY OF SPACE.
779
II. Complexes. Congruencies. Surfaces generated by a moving right line. Developable
surfaces and curves of double curvature.
11. A homogeneous equation between any six line-coordinates is said to represent the
complex of those lines the coordinates of which verify that equation. According to the
identity of ratios I. to VIII., the following equations,
F [{uv'—u'v), —{tv'—t'v), (tu'—t'u), {tw'—t’w), {uw'—u'w), {vw'—v'wj]= 0,
F[(xvr'— x1™), {y^1 —y'm), {zzj' —z'vs), {yz'—y'z), —{xz'—x'z), (xy'—x'yj] = 0,
F[cosa, cos/3, cosy, cicosX, ^cos^, &cost'] = 0,
F [fudv—vdu), —{tdv—vdt), { tdu—udt ), dt, du, dv]= 0,
F [dr, dy, dz, {ydz — zdy ), — {xdz — zdx), {xdy—ydx)~\= 0,
F[X, Y, Z, L, M, N]=0,
F [r, s, 1, (— «r), §, >?]= 0,
F[(— *)» ^p, q , 1]=0,
represent the same complex ; F being supposed to indicate always the same homogeneous
function of the different groups of line-coordinates. The complex is said to be of the nth.
degree , and represented by if its equations are of that degree.
12. Starting from the first equation,
Qre=F[(W— u'v), —{tv'—t'v), {tu'—t'u), {tw'—t'w), {uw'—u'w), {vvJ —v'w)~\= 0, . (1)
t, u, v, w and t', u', v', w' are to be referred to any two planes passing through any line
of the complex. Let one of the two planes {t1, u', v', w') be any given one. Then the
last equation, in regarding t', u', v', w' as constant and t, u, v, w as variable, represents
within the given plane a curve enveloped by tangent-planes {t, u, v, w). The lines of
the complex, confined within the plane, also envelope the same curve, the class of which
is the same as the degree of the complex. Hence
A complex of the nth degree being given, in each plane traversing space there is a
curve of the nth class enveloped by lines of the complex.
The equations of such curves fully agree with the general equation of the complex
itself. We have only to consider in this equation t' , u', v' , w' as constant in referring
them to the given plane, while t, u, v, w are regarded as variable plane-coordinates.
If %=1, the curve in each plane is replaced by a point; each line within the plane
passing through that point belongs to the linear complex.
If n= 2, the curves enveloped are conics, which may degenerate into systems of two
real or imaginary points.
13. If, in the second equation of the same complex,
xnn=F[{x-x'), {y-y'), (: z-z '), {yz'-y'z), -{xz'-x'z), {xy'-Ay)~\— 0, . (2)
where we put &'=■&=. 1, and X denotes a constant, x', y' , z' are referred to any given
780
DE. PLUCKEE ON A NEW OEOMETEY OE SPACE.
point in space and therefore regarded as constant, while x, y , z are the variable coordi-
nates of the points of any line of the complex, that equation represents a cone of the nth.
order, the geometrical locus of lines of the complex passing through the given point.
Hence
A complex of the nth degree being given , each point of space is the centre of a cone of
the nth order into which lines of the complex converge.
In linear complexes the lines meeting in a given point constitute a plane. If n— 2,
the cones are of the second order, and may degenerate into two real or imaginary
planes.
14. The right lines constituting a complex may be distributed either within planes
traversing space, or according to points into which they converge. We hitherto con-
sidered as a complex of right lines, the number of which is oo3. We may as well
regard it either as a complex of curves, or as a complex of cones, the number both of
curves and cones being oo2. Therefore we may say that
O„=0
represents at the same time as well in each plane a curve of the nth class as cones of the
nth order having each point of space as centre.
The curve in a plane revolving round a given line, or moving parallel to itself, gene-
rates a surface. The cone the centre of which describes a given right line envelopes
a surface. The number of surfaces both generated by the curve and enveloped by cones
is co. There is one of each kind of surfaces corresponding to any given line, all sur-
faces will be exhausted if that line turns in all directions round any of its points.
Accordingly we may likewise consider as a complex of surfaces, either described by
curves or enveloped by cones.
15. In denoting by g> any constant coefficient,
O„+^Om=0 (3)
represents an infinite number of complexes. The lines congruent in any two of them
belong simultaneously to all. All these congruent lines constitute a congruency (Q„, Qm),
which we say is represented by the equations of the two complexes.
• Each plane traversing space confines a curve of each of the two complexes, the mn
tangents common to both curves belong to the congruency. All curves within the same
plane belonging to the different complexes (3) which pass through the congruency,
touch the same mn of its lines. Again, each point is the centre of a cone belonging to
the different complexes (3). All such cones meet along the same mn[ lines, likewise
belonging to the congruency. Therefore in a congruency (Q„, Qm) there are mn lines
confined within each plane as there are mn lines passing through each point. The num-
ber of lines constituting a congruency is oo2.
If m— 1, there are in each plane n lines of the congruency (£2„, OJ passing through
the same point, as n of its lines converging into each point fall within the same plane ;
plane and point corresponding to each other.
DE. PLUCKEE ON A NEW GEOMETET OF SPACE.
781
1 6. In denoting by y and v any two constant coefficients,
Q=Q'+pQ''+»Q'w=0 (4)
represents an infinite number ( oo2 ) of complexes. All these complexes meet along the
lines which simultaneously belong to any three of them, especially to
O'=0, O"=0, O'"=0 (5)
By means of these equations the position of such a line is determined, after having arbi-
trarily assumed the value of one of the four constants upon which the line depends ; in
other terms, three of these four constants are functions of the fourth, varying each by
an infinitely small quantity if this one does. Hence we conclude that a line the coordi-
nates of which verify the three equations (5), generates a surface in passing successively
into all its positions. This surface (O', O", O'") is said to he represented hy the system of
the three equations (5).
17. Any point of space being given, there are three cones described by lines which
belong to the three complexes (5) and pass through the given point. Generally the
three cones (11) do not intersect along the same line. In certain positions only of
the point they do. In this case their common intersection belongs to the surface
(O', O", O'"), and therefore the point itself also.
Put
X' O' =F \_(x-x'\ (y—f), (z-z'), (yz'-y'z), -(xz'-x'z), (xy'-x'y)~\= 0,
X"0" =F" [(x—x’), (y-y'), (z-z'), (, yz'-y'z ), -(xz'-x'z), (xy'-x'y)]=0, •
X'"0" ' = F"' \_(x—x'), (y-y'), (z-z'), (yz'-y'z), -(xz'-x'z), (xy'-x'y)]=0.
(6)
If x', y' , z' are referred to any arbitrary point, and x, y, z regarded as variable, these
equations represent the three cones, (x’y'z') being their common centre, and their gene-
rating lines belonging to the three complexes (5). Without changing the conditions of
mutual intersection, the three cones may be moved parallel to themselves till the origin
of coordinates becomes their common centre. After that displacement their equations
are transformed into the following ones :
F' \x, y, z, (yz'-y'z), -(xz'-x’z), (xy’-x'y)'] = 0,
F" [x, y, z , (yz'-y'z), -(xz'-x’z), (xy’-x’y)]=0, (7)
¥"[x, y, z, (yz'-y'z), -(xz’-x’z), (xy’-x’y)] = 0. j
These equations being homogeneous with regard to (x, y, z), will, in the general case,
not be simultaneously verified by the three variables. In order to express that they
subsist simultaneously, we obtain, after having eliminated x, y, z,
<p(x’, y', z')= 0, (8)
<p indicating a function which involves the primitive constants of the three com-
plexes (5). This function might be rendered homogeneous by introducing w'. This
mdccclxv. 5 p
782 DE. PLtJCKEE ON A NEW GEOMETET OF SPACE.
equation, in regarding the coordinates as variable, represents in ordinary point-coordi-
nates the surface which in line-coordinates is represented by the system of the three
equations (5).
18. Likewise there are in each plane traversing space three curves enveloped by lines
of the three complexes Q! , O", QI". In the general case these curves have no common
tangent. In certain positions of the plane they have, and then the common tangent
belongs to the surface (O', O", O'"). Reciprocally, within a plane passing through any
generating line of the surface, the curves enveloped by the lines of any complex O touch
the generating line, and continue to do so if the plane revolves round it. The plane in
each of its positions is a tangent-jplane of the surface.
Put
O' = F [(uv'—u'v), —(tv'—t'v), (tu'—t'u), (t—f), (u—u1), (v— P)] = 0, j
0" = F"[(W— u'v), —(tv'—t'v), (tu'—t'u), (t—f), (u—u'), (v— P)]=0, l • (9)
0"'= F" \_(uv' — ulv), —(tv'—t'v), (tul—t'u), (t—f), (u—u'), (v— P)]=0. ]
In regarding t, u, v as variable plane-coordinates, and referring t', u', v' to the tra-
versing plane, these equations represent, within that plane, the three curves enveloped
by lines of the three complexes O', O", O'". On this account they may he reduced to
equations between two variables only, and therefore will not, in the general case, be
verified by any values of the three variables reduced to two. By eliminating the
variables between the last three equations, an equation,
^(f, u!,v')= 0, (10)
will be obtained, which, if t', u', v' are regarded as variable, represents in plane-coordi-
nates the surface (O', O", O'").
19. In order to derive the equations (9) from the equations (6) (both systems of equa-
tions representing the same surface), we may first pass from (6) to the three new equa-
tions,
F W-fz), -(xz'-x'z), (xy'-x'y), (x-x'), (y-y'), (z—z')]=0,
F '[(yz'-y'z), -(xz'-x'z), (xy'-x'y), (x-x'), (y-y1), (z-z’)]=0,
Y"\(yz'-y’z), -(xz'-x'z), (xy'-x'y), (x-x'), (y-y'), (*-*')]= 0,
and then replace x, y, z, x', y', z' by t, u, v, f, u’, v'. The last equations are likewise
obtained by merely exchanging amongst themselves the constant coefficients in each of
the three equations (6). The way of exchanging is obvious. Hence, in considering
that the equation (10) is derived exactly by the same algebraical operations from (9) as
(8) from (7), we may conclude that (10) may be derived from (8) by a mere exchange of
constants and a substitution of plane- for point-coordinates.
20. In a congruency (On, Qm) there are mn lines meeting in a given point. Two,
three, four of these lines may coincide. In this case the cones of both complexes
Qn and Om, the common centre of which is the given point, are tangent one to another,
or osculate each other along the double or multiple line. In order to get the analy-
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
783
tical expression of these new conditions, we may, as we did before, replace both cones
by such as have the origin as centre. In putting
the equations of these new cones may be written thus (No. 17),
f(?> <b z')=°,\
/£p, (b y\
(ii)
/"and/7 representing two functions of the variables^) and q, by means of which the lines
constituting the two cones are determined, x1, y\ z! being the coordinates of the given
point. If two of the mn intersecting lines of the two cones are coincident along any right
line (p, q), we get for the determination of that line, besides the two equations (11), the
following new one,
£
dq
which, if expanded, likewise assumes the form
f"(p, q, x’, y\ *>=0,
(12)
fn indicating a new function. By eliminating p and q between the three equations
(11) and (12), we get an equation of the form
W,y',z')= 0, (13)
representing, if at, y\ z' be regarded as variable, a developable surface , the locus of those
points through which double lines of the congruency pass, or, in other terms, the locus
of the double lines themselves.
In supposing that three intersecting lines of the two cones (11) fall within the same
line (p, q), the following new equation of condition is obtained
dj_ df
dp* \dq) dpdq dq dp dq9- \dp) dp dq
dtf(dfY_ o d?f df df dj1 / df'\ > = df-7f
dp* \dq) dpdq dq' dp ' dq 2 \dp) dp dq
which again may be expanded into an equation of the form
f"(p, q,x',y', z')= 0 (14)
This equation, combined with the three former equations (11) and (12), furnishes a new
equation of condition,
t(x',y',z')= 0 (15)
The system of the two equations (13) and (15) gives, as locus of points through which
triple lines of the congruency pass, a curve of double curvature.
In pursuing the same course a new equation of the same form as (13) and (15) is
5 p 2
784
DE. PLUCKER ON A NEW GEOMETRY OE SPACE.
obtained, which, combined with these, indicates that there is a certain number of points
into which quadruple lines of the congruency converge.
In congruencies of a peculiar description only we meet quintuple lines.
21. In quite the same manner we may determine the position of planes within
which two, three, four of the mn lines of the congruency (Q„, Om) coincide. In that
case both curves within the plane, enveloped by lines of the complexes Q,n and Qm,
touch or osculate one another on a common tangent.
In operating on the first two equations (9) as we did on the first two equations (6),
we get, in order to represent in plane-coordinates the locus enveloped by planes con-
fining a double line of the congruency, the following equation,
\p(t, u, v)= 0, (16)
which, as the remarks of No. 19 here likewise hold, is derived by a mere exchange of
constants from (10). Each plane passing through a double line being an enveloping
tangent plane of the represented surface, this surface degenerates into a curve of
double curvature.
Another equation may be derived from (15) in the same way. Let it be
vj /(#, u, v)=0, (17)
the system of the two equations (16) and (17) representing a developable surface , the
tangent planes of which confine the triple lines of the congruency. Finally, there are
certain tangent planes of the developable surface which confine the quadruple lines of
the congruency. These planes, as well as the points of the curve of double curvature
through which the quadruple lines pass, are determined by associated plane- and point-
coordinates, both being functions of the constants of the congruency, and are obtained
one from another by the above-mentioned exchange of these constants.
22. The double lines of a congruency constitute a surface , degenerated into a deve-
lopable one, as they envelope a surface, degenerated into a curve of double curvature.
The developable surface is represented in point-coordinates by a single equation (13), in
plane-coordinates by the system of two equations (16) and (17). The curve of double
curvature is represented in plane-coordinates by a single equation (16), in point-coordi-
nates by the system of two equations (13) and (15). The tangent-planes of the surface ,
confining triple lines of the congruency, osculate the curve ; the points of the curve ,
through which these triple lines pass, are osculating points of the surface , in which
three consecutive tangent planes meet. The curve , in certain points where the tangent
is an osculating one, is osculated by a plane in four points. Through such a point pass
four consecutive tangent planes of the surface , the common intersection of which is a
line of inflexion of the developable surface . The quadruple lines of the congruency
pass through such points, and are confined within such planes*.
* In two remarkable papers “ On a New Analytical Representation of Curves in Space,” published in the
third and fifth volume of the Quarterly Journal of Mathematics, Professor Cayley employed before me, in order
to represent cones, the six coordinates of a right line, depending upon any two of its points. Having lately
DR. PLtJCKER ON A NEW GEOMETRY OE SPACE.
785
III. On a new System of Coordinates.
23. We have hitherto determined the position of a right line in space in making use
of the ordinary system of three axes OX, OY, OZ intersecting each other. The new
question is whether we may substitute for this system another, by means of which we
are enabled to fix immediately the position of a right line without recurring to points
and planes.
In the ordinary system of coordinates, (1) the position of a point is determined by
means of three planes parallel to the planes of coordinates and meeting in that point,
(2) the position of a plane by a linear equation between the three coordinates of a point,
regarded as variable ; both point and plane depending upon three constants.
In an analogous way a right line is determined by the intersection of four linear
complexes. Such a linear complex depends upon the position of its axis and a con-
stant (paper presented, No. 29). A right line, regarded as the direction of a force ,
belongs to the complex, if the moment of rotation of the force with regard to the axis,
divided by its projection on the axis, be equal to the constant. Accordingly any four
axes in space being given, the position of a right line is fixed by means of four constants,
obtained by dividing the four moments of rotation with regard to the four axes by the
four corresponding projections on the same axes.
The four axes of the complexes constitute the new system of coordinates ; the four
constants are the four coordinates of the given right line. The right line intersecting
the four axes is the origin of coordinates, its four coordinates being equal to zero.
In the new system of coordinates a right line is determined in the most general way
by its four coordinates ; but an equation between the four coordinates is not in a general
way sufficient to represent a linear complex, depending as it does on five constants.
We may ad libitum increase the number of coordinates of a right line.
24. Let P, Q, R, S, T, U . . be the axes of any number of complexes, and p, q, r,s,t,u..
the corresponding coordinates of a given right line (according to the last number). Let
QP = Up—p=0, = q=0, £l=*r-r=0,
£ls = as— s=0, £=0, QM=E„ — u—0...
be the equations of the complexes. In order to express that the complexes meet along
the same line, the following equations of condition are obtained,
only seen the papers, I hasten to mention it now. But, besides the coincidence referred to, the leading views
of Professor Cayley’s paper and mine have nothing in common. On this occasion I may state that the prin-
ciples upon which my paper is based were advanced by me, nearly twenty years ago (Geometry of Space,
No. 258), but this had entirely escaped from my memory when I recurred to Geometry some time since.
786
DE. PLUCKER ON A NEW GEOMETRY OE SPACE.
where we may suppose that P, Q, E, S are the former four axes of coordinates ; x, x!, x, X',
I&&, v , v' indicate any constant coefficients.
In putting the coordinates q, r, s, t, u. . equal to zero, the general equations of the
complexes become
These new equations represent complexes of a peculiar kind, the lines of which inter-
sect their axes ; they may be said to represent the axes themselves.
In order to satisfy the equation (18), we put
whence
H p 4- X'H? + gJ ar + v' as, J
(19)
t —xj) -f-X^ -f -[hr +w, 1
u=xp+'k'q+[A'r-\-v's. j
(20)
The equations (19) require that the origin met by the axes P, Q, E, S be likewise met
by the new axes T, U . . .
Therefore q, r, s, t, u. . may be regarded as coordinates of the right line along
which all complexes meet ; the axes of the complexes intersecting the same right line
being the axes of coordinates. A right line being completely determined by the first
four coordinates, those remaining depend upon them by linear equations (20).
The system of four axes of coordinates depends upon 16, of five axes upon 19, of six
upon 22 constants.
Having thus established a system of coordinates which, independently of points and
planes, fixes the position of a right line in space, we are enabled, by regarding right lines
as elements of space, to reconstruct the whole geometry without recurring to the ordi-
nary system. Here we are guided by analogy. As far as I may judge, the task is a
most grateful but at the same time a long and laborious one.
IV. Geometry of Forces.
25. In recapitulating the contents of the first three paragraphs of this note, new con-
siderations have been suggested to me, which seem calculated, while greatly increasing
again this kind of inquiry, to put the key-stone to it. Hitherto, when I borrowed
technical terms from mechanical science, the only intention was to simplify the expression.
But force may be regarded as a merely geometrical notion, and there is only one step
more to be taken in order to arrive at a “ Geometry of Forces ,” as there is a geometry
based on the notion of right lines.
Forces depend upon five independent constants, four of which indicate their position,
while the fifth indicates their intensity. We may call these constants the five coordi-
nates of the forces.
DR. PLIJCKER ON A NEW GEOMETRY OF SPACE.
787
In order to fix the direction of a force, we may employ line-coordinates and choose the
following,
X, Y, Z, L, M, N,
indicating the projections of the force on the three axes of coordinates OX, OY, OZ,
and its three moments of rotation with regard to these axes. Between them the
following equation of condition holds good,
XL+YM+ZN=0
(see No. 7). The quotients obtained by dividing any five of them by the sixth are the
absolute values of coordinates. From these quotients the intensity of the force has dis-
appeared.
The same six constants , reduced by the last equation to five independent ones, may
he regarded as the absolute values of the coordinates of the force. Instead of homoge-
neous equations between them, if regarded as variable, representing complexes of lines
(of directions of the forces), we now get ordinary equations between the same variables
representing complexes of forces.
The extension of all former developments thus indicated immediately occurs to us.
A single instance may be referred to here. Forces constituting a linear complex are
such passing in all directions through each point of space as have their intensity equal
to the segments taken on their directions from the point to a certain plane corresponding
to it. Forces common to two linear complexes and passing through a given point are
confined within the same plane, the distance from the points where their directions meet
a given line within the plane being then intensity. Forces, the coordinates of which
verify simultaneously three linear equations, are distributed through space in such a
manner that there is one force of a given intensity passing through each point of space,
or, as we may add, confined in each plane.
The general contents of this note (except § IV.) were in a verbal communication pre-
sented by me at the last Birmingham Meeting of the British Association. As they
concern the principles on which the original paper is based, giving to them a symmetry
and a generality I was not before aware of, I thought it necessary to add the note
to that paper. At the same time I also endeavoured to give an idea of the great ferti-
lity of the method developed. But as I am now preparing a volume for publication on
this subject, I do not think it suitable to enter here into any details. The work will
embrace the theory of the general equation of the second degree between line-coordi-
nates, requiring no means of discussion but those employed by me in the case of equa-
tions of the same degree between point- or plane-coordinates. The complex of lines
represented by such an equation may be regarded likewise as a complex of curves of the
second class, one of which is confined in each plane, or as a complex of cones of the
second order, each point of space being the centre of such a cone. In reducing the
number of constants upon which the complex depends from 19 to 9, we pass in parti-
788
DR. PLUCKER ON A NEW GEOMETRY OF SPACE.
cularizing step by step from the general complex to a surface of the second order and
class, determined by its tangents.
I intend resuming the consideration of the mechanical part of this note. Then a last
generalization will occur to us, the equation of condition, hitherto admitted between
the six coordinates x, y, z, L, M, N, being removed.
CONTENTS.
I. On Linear Complexes of Might Lines.
Preliminary explanations. — Point-coordinates. Equations between them representing
surfaces by means of their points. Plane coordinates. Equations between them repre-
senting surfaces enveloped by planes, 1. Double definition of right lines, either by
means of their points or by means of traversing planes. Pays. Axes. The two pro-
jections of a ray within two planes of coordinates depend upon four linear constants,
which may be regarded as ray-coordinates, r, s, g, <r and t, u, vx, vy. The two points in
which two planes of coordinates are intersected by an axis, depend upon four linear
constants which are its coordinates, x, y, zt, zu and p, q, vr, z, 2-5. Complexes of rays or
axes represented by one equation between their four coordinates. Congruent lines of
two complexes constitute a congruency, of three complexes a configuration ( surface
gauche). In a complex every point is the vertex of a cone, every plane contains an
enveloped cone. In a congruency there is a certain number of right lines passing
through a given point, and confined within a given plane, 6, 7. A configuration of rays
represented by three linear equations, either between r, s, g, a or £, u, vx, vy, is a para-
boloid, or a hyperboloid, 8. A configuration of axes represented by three equations,
either between p, q, -a. z or x , y , zt, zu, is either a hyperboloid or a paraboloid, 9. In a
congruency of rays or axes represented by two linear equations, there is one ray and one
axis passing through a given point and confined within a given plane, 10. Construction,
by means of two fixed points, of the rays of a congruency represented by two linear
equations between t , u, vx, vp 11. Construction, by means of two planes, of the axes of
a congruency represented by two linear equations between x, y, zt, zu, 12.
Linear complexes of rays. — In a complex represented by a linear equation between
r, s, g, <r, all rays traversing a given point constitute a plane ; all rays confined within a
given plane meet in the same point. Points and planes corresponding to each other
13-15. A new variable (sg— re) introduced. The general equation of a linear complex
is Ar+Bs-f-C+D<7-|-E^+F(^— r<r)=0. Equation of a plane corresponding to a given
point, of a point corresponding to a given plane, 16-19. Conjugate right lines.
Each ray intersecting any two conjugate lines is a ray of the complex. A ray of the
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
789
complex may be regarded as two congruent conjugate lines. Principle of polar reci-
procity applied, 20. Construction of the plane corresponding to a given point, of the
point corresponding to a given plane, 21, 22. Geometrical determination of the con-
stant of the general equation of the complex. There is a characteristic direction given
by the double equation ^-= = If that direction falls within xy , the term (sg—rv)
disappears and the general equation becomes linear. If any plane perpendicular to it is
taken as one of the three planes of rectangular coordinates, and the corresponding point
within it as origin, the general equation assumes one of the forms, s=kg, r=ka,
sg—rtr=k. A linear complex may, without being altered, turn round a fixed line, and move
along it parallel to itself, 23-29. Geometrical interpretation of the last equations, 30.
Points and planes corresponding to one another with regard to the complex sg—ra=.k.
Geometrical interpretations, 31, 32. Generalization, 33. Conjugate lines with regard
to the complex sg — r<r=k, 34. A linear complex depends upon five constants, four of
which give the position of its axis, 35. Formulse of the transformation of ray-coordinates
corresponding to any displacement of the axes of coordinates, 36-38. Analytical deter-
mination of the axis of a complex, represented by the general equation. Determination
of k, 39-43. In the peculiar case in which k is equal to zero, all rays meet the axis of
the complex, 44. Rays passing through the same point, 45.
Linear congruencies of rays. — A linear congruency, along which an infinite number of
complexes intersect each other, is represented^ by the equations of any two of them.
Through a given point of space only one ray passes, corresponding to that point, as there
is only one ray confined within a given plane, 46. There is in each complex passing
through the congruency one line conjugate to a given right line : all these lines belong
to one generation of a hyperboloid, the second generation of which contains rays of the
congruency. Generation of a linear congruency by a variable hyperboloid, 47-49.
Characteristic section of a congruency to which the axes of all passing complexes are
parallel. The axis of the congruency is a fixed right line, perpendicular to that section
on which the axes of all complexes meet at right angles, 50, 51. The locus of points
having in all complexes the same corresponding plane is a system of two right lines, the
directrices of the congruency. Central plane parallel to both directrices and equidistant
from them. The directrices may be real or imaginary, 52-54. In the first case there
are amongst the complexes two of a peculiar description [44] having both directrices as
axes. All rays of the congruency meet both its directrices, 55. The peculiar case in
which one of the two directrices is infinitely distant, 56. Each of any two complexes
being given by means of its constant k and the position of its axis, to determine both
directrices of the congruency, 57-59. A congruency being given by means of its two direc-
trices, to determine the constants and the axes of the complexes passing through it.
Centre of the congruency. The two secondary axes within the central plane, 60. Locus
of the axes of all complexes meeting along the same congruency, 61.
Linear configurations of rays represented by the equations of three linear complexes.
mdccclxv. 5 Q
790
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
An infinite number of congruencies meet along a linear configuration. Generally it is a
hyperboloid. Its rays constitute one of its generations, while the directrices of all con-
gruencies constitute the other, 62. The central planes of all congruencies meet in the
same point : the centre of the configuration. Its diameters meet both directrices of the
different congruencies, 63. A configuration is determined by means of three complexes,
or by means of three congruencies, obtained by combining them two by two. Three
couples of planes drawn through both directrices of each of the congruencies parallel to
its central plane constitute a parallelopiped circumscribed to the hyperboloid. Each ray
intersects all six directrices. The ray within each of the six planes is parallel to the
directrix within the opposite plane ; the point in which it meets the directrix within
the same plane is the point of contact. Three diameters determined by both points of
contact within the three couples of opposite planes. Imaginary diameters correspond
to imaginary directrices, asymptotes to congruent directrices, 64. A hyperboloid being
given, we may return to the congruencies and complexes which constitute it, 65. The
equations of the configurations transformed into an equation between x , y, z, 66.
II. On Complexes of Luminous Bays within Biaxal Crystals.
Complexes of doubly refracted rays corresponding to complexes of incident rays, 1.
Digression on double refraction. Huyghexs’s principle. The author’s construction
presented, 1838. Auxiliary ellipsoids. The ellipsoid E, with regard to which the wave-
surface is its own polar surface. The plane of refraction, containing both refracted
rays, passes through SS, the polar line of RR, along which the surface of the crystal is
intersected by the front of the incident elementary wave at that moment when, within
the crystal, the wave-surface is formed, 2-6. Tlie plane of refraction is congruent with
the diametral plane of E, the conjugate diameter of which is perpendicular to the
plane of incidence hi O, 7. All rays incident within the same plane are, after double
refraction, confined again within the same plane, 8. While the plane of incidence
turns round the vertical in O, the corresponding plane of refraction turns round that
diameter of E, the conjugate diametral plane of which is the surface of the crystal, 9,
10. Whatever may be the plane or curved surface met by an incident ray in any given
point O, all corresponding planes of refraction pass through a fixed right line, 11.
Peculiar cases of complexes. The plane of refraction perpendicular to the surface of
the crystal. The incident and the two refracted rays confined within the same plane.
A circular section of E falling within the surface of the crystal, 12, 13. Analytical
determination of SS, 14. A fourth auxiliary ellipsoid, 15, 16.
Complex of doubly refracted rays determined by means of E. Its equation depend-
ing upon the constants of E, 17, 18. By taking as axes of coordinates three conjugate
diameters of E, two of which, falling within the surface of the crystal, are perpendicular
to each other, the general equation of the complex becomes ra—hs^ the constant Jc
being the ratio of the squares of the two rectangular diameters, 19. Geometrical in-
terpretation, 20. Refracted rays of the complex passing through a given point consti-
DR. PLUCKER ON A NEW GEOMETRY OE SPACE.
791
tute a cone of the second order. The cone remains the same if the given point moves
along a right line, passing through O, 21. Peculiar cases, 22-24. A hyperbola enve-
loped by the doubly refracted rays within any given plane. Its determination, 25.
Peculiar cases. Geometrical interpretations, 26-28. The complex generated in three
different ways by a variable linear congruency, 29. Peculiar case of a complex, the
crystal being cut along a circular section of E. All doubly refracted rays meet that
diameter of E the conjugate plane of which is the circular section, 30. Peculiar case
in which the surface of the crystal is a principal section, 31. Case of uniaxal crystals,
32, 33. The ellipsoid E replaced by a new ellipsoid, the radii vectores of which indicate
the reciprocal values of optical elasticity, 34.
Additional Note.
Coordinates of a right line, 1-10. Complexes. Congruencies. Surfaces generated
by a moving right line. Developable surfaces and curves of double curvature, 11-22.
A new system of coordinates, 23, 24. Geometry of forces, 25.
INDEX
TO THE
PHILOSOPHICAL THAN SACTIONS
FOR THE YEAR 1865.
A.
Antedon rosaceus, embryogeny of, 513 (see Thomson).
Armour-plated ships, magnetic character of, 263 (see Evans).
Atlantic, principal currents of the, 239 (see Forchhammek).
Atomic heat and atomic weight, relations between, 177 (see Kopp).
B.
Bailey (J. W.), his researches on Foraminifera, 423 (see Parker).
Bakerian Lecture, 605 (see Roscoe).
Beale (L. S.). New Observations upon the Minute Anatomy of the Papillse of the Frog’s Tongue, 443.
— Conclusions, 456; description of the plates, 457.
Binney (E. W.). A Description of some Fossil Plants, showing Structure, found in the Lower Coal-
seams of Lancashire and Yorkshire, 579. — Concluding remarks, 596 ; description of the plates, 599.
Blood, influence of physical and chemical effects upon, 687 (see Harley).
C.
Cayley (A.). On the Sextactic Points of a Plane Curve, 545. — Application to a cubic, 556 ; Appendix,
569.
Cerebral hemispheres of the Marsupialia and Monotremata, 633 (see Flower).
Chemical action of total daylight, 605 (see Roscoe).
Comatula rosacea , embryogeny of, 513 (see Thomson).
Compass, effect of ship’s magnetism on the, 263 (see Evans).
Complexes, linear, of right lines, 725 (see Plucker).
Condensers, electric, theory of, 493 (see Maxwell).
Cubic curve, sextactic points of, 556 (see Cayley).
794
INDEX.
D.
Double refraction, 760 (see Plucker).
E.
Echidna Hystrix, 671 (see Owen).
Electromagnetic field, dynamical theory of, 459 (see Maxwell).
Elements, nature of the chemical, 199 (see Kopp).
Evans (F. J.) and Smith (A.). On the Magnetic Character of the Armour-plated Ships of the Royal
Navy, and on the Effect on the Compass of particular arrangements of Iron in a Ship, 263. — De-
duction of the formulae employed, 267 ; physical representation of the results, 271; numerical
values of the coefficients, 278; tables of coefficients, 291 ; effect on the compass of particular masses
of soft iron in a ship, 304.
F.
Flower (W. H.). On the Commissures of the Cerebral Hemispheres of the Marsupialia and Monotre-
mata as compared with those of the Placental Mammals, 633. — Description of the plates, 650.
Foraminifera from the Atlantic Ocean, &c., 325 (see Parker).
Forchhammer (G.). On the Composition of Sea-water in the different parts of the Ocean, 203. — -
Elements which occur in the water of the ocean, 204; on the quantitative analysis of sea- water,
214; distribution of the salts in different parts of the sea, 219; general results of the preceding
investigation, 226 ; principal currents of the Atlantic, 239 ; chemical decomposition in sea-water,
242 ; tables, 246.
Fossil plants found in coal-seams, 579 (see Binney).
Frog’s tongue, minute anatomy of the papillae of, 443 (see Beale).
G.
Gases, spectra of, 1 (see Plucker).
Geometry, on a new, of space, 725 (see Plucker) .
Glyptodon, osteology of, 31 (see Huxley).
H.
Harley (G.). On the Influence of Physical and Chemical Agents upon Blood; with special reference
to the mutual action of Blood and the Respiratory Gases, 687. — Influence of physical agents, 689 ;
of chemical agents — animal products, 699; of vegetable products, 704; of anaesthetics, 713; of
mineral substances, 718.
Hittorf (J. W.) and Plucker (J.). On the Spectra of Ignited Gases and Vapours, &c., 1 (see
Plucker).
Hoplophoridce, 31 (see Huxley).
Huxley (T. H.). On the Osteology of the germs Glyptodon, 31. — Part I. History of the discovery and
determination of the remains of the Hoplophoridae, 31. Part II. Description of the skeleton of
Glyptodon clavipes, 43 ; of the skull, 43 ; of the vertebral column, 58; description of the plates, 69.
INDEX.
795
I.
Induction, electromagnetic, 466 (see Maxwell).
J.
Jones (T. R.) and Parker (W. K.). Foraminifera from the Atlantic Ocean, 325 (see Parker).
K.
Kopp (H.). Investigations of the Specific Heat of Solid Bodies, 71. — Historical introduction, 71 ;
description of a method of determining the specific heat of solid bodies, 83 ; determination of the
specific heat of individual solid substances, 103 ; table of the substances whose specific heat has
been experimentally determined, 167 ; on the relations between atomic heat and atomic weight or
composition, 177; considerations on the nature of the chemical elements, 199.
L.
Light, electromagnetic theory of, 497 (see Maxwell).
M.
Magnetic character of ships, 263 (see Evans).
Marsupialia, cerebi’al characters of the, 633 (see Flower).
Maxwell (J. C.). A Dynamical Theory of the Electromagnetic Field, 459. — Introduction, 459; on
electromagnetic induction, 466 ; general equations of the electromagnetic field, 480 ; mechanical
actions in the field, 488 ; theory of condensers, 493 ; electromagnetic theory of light, 497 ; calcu-
lation of the coefficients of electromagnetic induction, 506.
Meteorological registration of the chemical action of total daylight, 605 (see Roscoe).
Monotremata, cerebral characters of the, 633 (see Flower).
N.
Nitrogen, different spectra of, 6 (see Plucker).
O.
Owen (R.). On the Marsupial Pouches, Mammary Glands, and Mammary Foetus of the Echidna
Hystrix, 671. — Description of the plates, 685.
P.
Parker (W. K.) and Jones (T. R.). On some Foraminifera from the North Atlantic and Arctic
Oceans, including Davis Straits and B n’s Bay, 325. (For Contents, see p. 325.)
796
INDEX.
Plucker (J.) and Hittorf (J. W.). On the Spectra of Ignited Gases and Vapours, with especial re-
gard to the different Spectra of the same elementary gaseous substance, 1. — Different spectra of
nitrogen, 6 ; spectra of the first and second orders, 13 ; spectra of sulphur and various other
elements, 13 ; explanation of the plates, 26.
Plucker (J.). On a New Geometry of Space, 725. — On linear complexes of right lines, 725 ; on com-
plexes of luminous rays within biaxal crystals, 760. Additional note, 774. (For Contents, see
p. 788.)
Poisons, influence of various, upon blood, 687 (see Harley).
Pourtales (F. L.), his researches on Foraminifera, 429 (see Parker).
R.
Roscoe (H.E.). The Bakerian Lecture. On a Method of Meteorological Registration of the Che-
mical Action of Total Daylight, 605. — Tables of results, 624.
S.
Sea-water, composition of, in different parts of the ocean, 203 (see Forchhammer).
Sextactic points of a plane curve, 545 (see Cayley); 653 (see Spottiswoode).
Sigillaria, 579 (see Binney).
Smith (A.) and Evans (F. J.). On the Magnetic Character of the Armour-plated Ships of the Royal
Navy, &c., 263 (see Evans).
Specific heat of solid bodies, 71 (see Kopp).
Spectra, different, of the same elementary substance, 1 (see Plucker).
Spottiswoode (W.). On the Sextactic Points of a Plane Curve, 653.
T.
Thomson (Wyville). On the Embryogeny of Antedon rosaceus, Linck ( Comatula rosacea of Lamarck),
513. — Explanation of plates, 542.
V.
Velocity of light, deduction of, from electromagnetic data, 499 (see Maxwell).
W.
Wave-surface in biaxal crystals, 761 (see Plucker).
f
LONDON:
PRINTED BY TAYLOE AND FRANCIS, RED LION COURT, FLEET STREET.
PRESENTS
RECEIVED BY
THE ROYAL SOCIETY,
WITH THE
NAMES OF THE DONORS.
From November 1864 to June 1865.
Presents.
ACADEMIES and SOCIETIES.
Albany : —
Transactions of the Society for the Promotion of Useful Arts in the State
of New York. Yol. IV. Part 2. 8vo. Albany 1819.
Transactions of the Albany Institute. Yol. IY. 8vo. Albany 1858-64.
Basel : — Verhandlungen der Naturforschenden Gesellschaft. Theil IV. Heft
1. 8vo. Basel 1864.
Berlin : —
Abhandlungen der Konigliehen Akademie der Wissenschaften, aus dem J ahre
1863. 4to. Berlin 1864.
Monatsbericbt. January and February, and June to December, 1864. 8vo.
Berlin.
Die Fortschritte der Physik im Jahre 1862, dargestellt von der physikali-
scben Gesellschaft. Jahrgang XYIII. 8vo. Berlin 1864.
Berliner Astronomisches Jahrbuch fiir 1867. 8vo. Berlin 1864.
Bern : —
Mittheilungen der Naturforschenden Gesellschaft, aus dem Jahre 1863.
Nr. 531-552. 8vo. Bern 1863.
Programm der Berner Kantonsschule fiir das Jahr 1864. 8vo. Bern 1864.
Yerzeichniss der Vorlesungen welche vom 15. Oct. 1863-31. Marz 1864, 15.
April-15. Aug. 1864, 15. Oct. 1864-31. Marz 1865 an der Hochschule in
Bern gehalten werden sollen. 4to. Bern.
Yerzeichniss der Behorden, Lehrer und Studirenden der Berner Hochschule,
1863-64. 8vo. Bern.
Beitrag zur Casuistik der Beckengeschwiilste in geburtshUlflicher Beziehung,
von J. U. Kiirsteiner. 8vo. Zurich 1863.
Donors.
The Institute.
The Society.
The Academy.
The Society.
The Observatory.
The Society.
MDCCCLXV.
a
[ 2 ]
Presents.
ACADEMIES and SOCIETIES {continued).
Bern : —
Beitrage zur Lehre yon den Luxationen und Eracturen der obersten Hals-
wirbel, von C. R. Wagner. 8vo. Zurich 1863.
Einige Versuche iiber Strychnin- Yergiftung als gerichtlich-toxikologischer
Beitrag zu den Strychnin- Yergiftungen, yon J. Meyer. 8vo. Bern 1864.
Ueber angeborne Stenose der Arteria pulmonalis, von C. Stolker. 8vo.
Bern 1864.
Berwick: — Berwickshire Naturalists’ Club. Proceedings. Yol. Y. No. 2. 8vo.
1865.
Birmingham : — Institution of Mechanical Engineers. Proceedings, 5th Novem-
ber 1863 ; 28th January, 5th May, 2nd August 1864 (2 parts). 8vo.
Bologna : —
Memorie della Accademia delle Scienze dell’ Istituto. Tomo 12. Serie 2,
tomo 1 & 2. 4to. Bologna 1861-62.
Rendiconto delle Sessioni 1860-61, 1861-62, 1862-63. 8vo. Bologna.
Bordeaux: — Memoires de la Societe des Sciences Physiques et Naturelles.
Tome III. cahier 1. 8vo. Paris 1864.
Boston, U.S. : —
Society of Natural History. Boston Journal of Natural History. Yol. YII.
No. 4. 8vo. Boston 1863.
Breslau : — ■
Abhandlungen der Schlesischen Gesellschaft fur vaterlandische Cultur.
Abth. fur Naturwissenschaften und Medicin. 1862, Heft 3. Phil.-Hist.
Abth. 1864, Heft 1. Einundvierzigster Jahresbericht. 8vo. Breslau 1864.
Bruxelles : —
Memoires de l’Academie Royale des Sciences, des Lettres et des Beaux-Arts.
Tome XXXIV. 4to. Bruxelles 1864.
Memoires Couronnes et Memoires des Savants Etrangers. Tome XXXI.
4to. Bruxelles 1863.
Bulletins. 2e serie. Tomes XY., XVI., XYII., XYIII., & XIX. Nos. 1-4.
8vo. Bruxelles 1863—65.
Memoires Couronnes et autres Memoires. Collection in-8vo. Tomes XY. &
XYI. 8vo. Bruxelles 1863-64.
Annuaire 1864 & 1865. 8vo. Bruxelles 1864-65.
Bulletin de l’Academie Royale de Medecine. Tome YII. Nos. 3-6, 8-11 ;
Tome YHI. Nos. 1-2. 8vo. Bruxelles 1864—65.
Calcutta: —
Asiatic Society of Bengal. Journal, 1864, Nos. 1-5 and Supplementary No.
8vo. Calcutta 1864.
Memoirs of the Geological Survey of India. Vol. III. Part 2, Yol. IY. Part 2.
8vo. Calcutta 1864.
— r Palseontologia Indica: III. 2-5.
The Eossil Cephalopoda. 4to. Calcutta 1864.
Memorandum on the results of a cursory examination of the Salt-range in
the Punjab and of parts of Bunnoo and Kohat. 8vo. Calcutta 1864.
Annual Report of the Geological Survey of India and of the Museum of
Geology. 8vo. Calcutta 1864.
Donors.
The Society.
The Club.
The Institution.
The Institute.
The Society.
The Society.
The Society.
The Academy.
The Academy.
The Society.
The Geological Museum.
L 3 ]
Presents.
ACADEMIES and SOCIETIES ( continued ).
Cambridge (Mass.) : —
Harvard College. Annual Reports of the President and Treasurer, 1862-63.
8vo. Cambridge 1864.
Report of the Committee of the Overseers appointed to visit the Observatory.
8vo. Boston 1864.
Catalogus Universitatis Harvardianse 1863. 8vo.
Catalogue of the Officers and Students, 1863-64. 8vo. Cambridge 1863.
Address delivered before the Alumni. 8vo. Cambridge 1863.
Addresses at the Inauguration of Thomas Hill, D.D., as President. 8vo. Cam-
bridge 1863.
Catania: — Atti dell’ Accademia Gioenia di Scienze Naturali. Serie seconda.
Tomo I.-XVL & XIX. 4to. Catania 1844-64.
Cherbourg: — Memoires de la Soeiete Imperiale des Sciences Naturelles.
Tomes IX. & X. 8vo. Paris 1863-64.
Christiania : —
Forhandlingar i Yidenskabs-Selskahet. Aar 1863. 8vo. Christiania 1864.
Nyt Magazin for N aturvidenskaberne. Bind XII. Heft 4, Bind XIII. Hefte
1-3. 8vo. Christiania 1863-64.
Meteorologische Beobachtungen ; aufgezeichnet auf Christiania’s Observa-
torium. Lief. 3 & 4. 4to. Christiania 1864.
Det Xongelige Norske Erederiks Universitets Aarsberetning for Aaret 1862.
8vo. Christiania.
Index Scholarum in Universitate Regia Eredericiana Jan. & Aug. 1864.
4to. Christiania.
Om Sneebrseen Eolgefon, af S. A. Sexe. 4to. Christiania 1864.
Om de Geologiske Eorhold paa Kystroekningen af Xordre Bergenhus Amt,
af M. Irgens og Th. Hiortdahl. 4to. Christiania 1864.
Chur : — Yerhandlungen der Schweizerischen naturforschenden Gesellschaft bei
ihrer Yersammlung zu Samaden Aug. 1863. 47 Versammlung. 8vo.
Chur.
Columbus : — Ohio State Board of Agriculture. Seventeenth Annual Report.
8vo. Columbus 1863.
Copenhagen : — Oversigt over det Kgl. danske Yidenskabernes Selskabs For-
handlinger, 1862 & 1863. 8vo. Kjobenhavn.
Devonshire Association for the Advancement of Science, Literature, and Art.
Reports and Transactions. Parts 1-3. 8vo. London 1863-64.
Dijon : — Memoires de l’Academie Imperiale des Sciences, Arts et Belles-Let-
tres. Serie 2. Tome XI. Annee 1863. 8vo. Dijon 1864.
Dresden: — Nova Acta Academise Csesarese Leopoldino-Carolinse Germanic*
Natur* Curiosorum. Tomus XXXI. 4to. Dresdce 1864.
Dublin : —
Geological Society. Journal. Yol. X. Part 2. 8vo. Dublin 1864.
Natural History Society. Proceedings. Yols. I., II. Parts 2 & 3 ; Yol. III.
Parts 1 & 2 ; Yol. IY. Parts 1 & 2. 8vo. Dublin 1849-65.
Royal Dublin Society. Journal. Nos. 31, 32 & 33. 8vo. Dublin 1864-65.
Royal Irish Academy. Transactions. Yol. XXI Y. Antiquities, Part 2. 4to.
Dublin 1864.
a 2
Donors.
The College.
The Academy.
The Society.
The University.
The Society.
The Board.
The Society.
The Association.
The Academy.
The Academy.
The Society.
The Society.
The Society.
The Academy
[ * ]
Presents.
ACADEMIES and SOCIETIES ( continued ).
Dudley: — Dudley and Midland Geological and Scientific Society and Field
Club. Transactions. Nos. 1-5. 8vo. Dudley 1862-65.
Edinburgh : —
Royal Scottish Society of Arts. Transactions. Yol. VI. Part 4. 8vo. Edin-
burgh 1864.
Royal Society. Transactions. Yol. XXIII. Part 3. 4to. Edinburgh 1864.
Proceedings. Session 1863-64. 8vo. Edinburgh 1864.
Frankfurt a. M. : —
Abhandlungen herausgegeben von der Senckenbergischen naturforschenden
Gesellschaft. Band V. Heft 2. 4to. Frankfurt a. M. 1864.
Der Zoologische Garten, Organ der zoologischen Gesellschaft. Jahrgang I.,
II., III., IV., & V. Nr. 2-12. 8vo. Frankfurt a. M. 1860-64.
Freiburg im Breisgau: — Berichte fiber dieVerhandlungen der naturforschenden
Gesellschaft. Band III. Heft 2. 8vo. Freiburg 1864.
Geneva: — Memoires de la Soeiete de Physique et d’Histoire Naturelle.
Tome XVII. Partie 2. 4to. Genbve 1864.
Gorlitz : —
Abhandlungen der naturforschenden Gesellschaft. Band I.-XII. (wanting
B. III. Heft 1, and B. VII.). 8vo. Gorlitz 1827-65.
Die Regenverhaltnisse Deutschlands, Abdruck aus den Abhandlungen, Band
VII. Heft 1. 8vo. Gorlitz 1865.
Gottingen : — Nachrichten von der K. Gesellschaft der "Wissenschaften und der
Georg- August-Universitat, aus dem Jahre 1864. 12mo. Gottingen 1865.
Haarlem: — Natuurkundige Verhandelingen van de Hollandsehe Maatschappij
der Wetenschappen. Tweede Verzameling. Deel XVIII., XIX., & XXI.
Stuck 1. 4to. Haarlem 1863-64.
Habana : — Observatorio Magnetico y Meteorologico del Real Colegio de Belen
de la Compahia de Jesus. Resumen de las Observaciones. Nov., Dec.
1863 ; Jan.-Dee. 1864; Jan.-March 1865. 8vo.
Halle : — Zeitschrift ffir die gesammten Naturwissenschaften, herausgegeben
von dem naturw.Vereine ffir Sachsen und Thfiringen in Halle, redigirt von
C. Giebel und M. Siewert. Jahrg. 1864. Band XXIII. 8vo. Berlin 1864.
Hobart Town : — Report of the Royal Society of Tasmania for the year 1863.
8vo. Hobart Town 1864.
Jena: — Jenaische Zeitschrift ffir Medicin und Naturwissenschaft, herausgege-
ben von der medicinisch-naturwissenschaftlichen Gesellschaft zu Jena.
Band I. Hefte 2-3. 8vo. Leipzig 1864.
Kazan : — Imperial Russian University. Outchonia Zapiski (Scientific Papers),
1862. 4 Parts. 8vo. Kazan 1862-63.
Kiel: — Schriften der Universitat, aus dem Jahre 1863. Band X. 4to. Kiel
1864.
Kolozsvartt : — Az Erdelyi Muzeum-Egylet Evkonyvei. Kotet III. Fiizet 1.
4to. Kolozsvartt 1864.
Konigsberg: — Schriften der koniglichen physikalisch-okonomischen Gesell-
schaft. Jahrgang 1863. Abth. 1 & 2. 4to. Konigsberg 1863.
Lausanne : — Bulletin de la Soeiete Vaudoise des Sciences Naturelles. Tome
VII. No. 50 ; tome VIII. Nos. 51 & 52. 8vo. Lausanne 1863-65.
Donors.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
The Observatory.
The Society.
The Society.
The Society.
The University.
The University.
The Museum.
The Society.
The Society.
[ 5 ]
Donobs.
ACADEMIES and SOCIETIES ( continued ).
Leeds : —
Geological and Polytechnic Society of the West Riding of Yorkshire. Pro-
ceedings, December 6, 1839 ; 1840-42, pp. 1-442 (5 parts) ; 1863-64.
8vo. Leeds 1839-64.
Philosophical and Literary Society. Annual Reports for 1861-62 & 1863-64.
8vo. Leeds 1862-64.
On the Early History of Leeds in Yorkshire. A Lecture by T. Wright.
8vo. Leeds 1864.
Leipzig : —
Berichte iiber dieYerhandlungen der koniglich-sachsischen Gesellschaffc der
Wissenschaften. Math.-Phys. Classe, 1863, 1 & 2 ; Phil.-Hist. Classe,
1863, 1-3 ; 1864, 1. 8vo. Leipzig 1863-64.
Darlegung der theoretischen Berechnung der in den Mondtafeln angewand-
ten Storungen, von P. A. Hansen. Zweite Abhandlung. 8vo. Leipzig 1864.
Elektrodynamische Maassbestimmungen insbesondere iiber elektrische
Schwingungen, von W. Weber. 8vo. Leipzig 1864.
Lisbon : —
Memorias da Academia Real das Sciencias. Classe de Sciencias Mathema-
ticas, Physicas e Naturaes : nova serie, Tomo III. parte 1. Classe de
Sciencias Moraes, Politicas e Bellas Lettras : nova serie, Tomo III. partel.
4to. Lisboa 1863.
Annaes do Observatorio do Infante D. Luiz. Yol. 1. 1856 a 1863 ; Yol. II.
1863-64, Nos. 1-3. fol. Lisboa 1864.
Relatorio do Servigo do Observatorio do Infante D. Luiz, 1863-64. 8vo.
Lisboa 1864.
Liverpool : —
Historic Society of Lancashire and Cheshire. Transactions. New Series.
Yol. III. 8vo. Liverpool 1863.
Literary and Philosophical Society. Proceedings, 1863-64. No. 1 8. 8vo.
London 1864.
London : —
Anthropological Society. Anthropological Review. Nos. 4-8. 8vo. London
1864^65.
k British Association. Report of the Thirty-third Meeting, held at Newcastle-
upon-Tyne, 1863. 8vo. London 1864.
— — — — Index to Reports and Transactions from 1831 to
1860 inclusive. 8vo. London 1864.
British Horological Institute. The Horological Journal. Vol. YI. Nos. 71
& 72 ; Yol. YII. Nos. 73-82. 8vo. London 1864-65.
British Meteorological Society. Proceedings. Yol. II. Nos. 13-19. 8vo.
London 1864-65.
Catalogue of Books in the Library, 1864.
List of Members, 1864. 8vo.
Chemical Society. Journal. July to December 1864; January to April
1865. 8vo. London.
Entomological Society. Transactions. Third series. Yol. II. Parts 1-4.
Yol. III. Part 1. 8vo. London 1864-65.
The Society.
The Society.
The Society.
The Academy.
The Observatory.
The Society.
The Society.
The Society.
The Association.
The Institute.
The Society.
The Society.
The Society.
[ 6 ]
Presents.
ACADEMIES and SOCIETIES ( continued ).
London : —
Geological Society. Quarterly Journal. Nos. 79-82. Yol. XX. Parts 3 & 4 ;
Vol. XXI. Parts 1 & 2. 8vo. London 1864-65.
Geological Survey of Great Britain, Memoirs. Catalogue of the Collection
of Fossils in the Museum of Practical Geology. By T. H. Huxley and
B. Etheridge. 8vo. London 1865.
Catalogue of the Mineral Collections. By W. W. Smyth,
T. Beeks, and F. W. Budler. 8vo. London 1864.
Descriptive Catalogue of the Bock Specimens. 8vo.
London 1862.
Descriptive Catalogue of the Geological, Mining, and
Metallurgical Models. 8vo. London 1865.
Catalogue of the published Maps, Sections, Memoirs,,
and other publications. 8vo. London 1865.
Iron Ores of Great Britain. Parts 3 & 4. 8vo. London
1861-62.
Mineral Statistics of the United Kingdom for 1861,
1862, and 1863. 8vo. London 1862-64.
Memoirs illustrative of the Geological Map, Sheets 4, 7,
10, 12, 13, 45, 53 N.E., 71 N.E., 80 N.E., 82 S.E., 88 S.W., 89 S.W.,
89 S.E., Scotland Sheets 32 & 34. 8vo. London 1861-64.
Figures and Descriptions illustrative of British Organic
Bemains. Decades 10 & 11. 4to. London 1861-64.
Institution of Civil Engineers. Minutes of Proceedings, Session 1861-62.
Yol. XXI. 8vo. London 1862. General Index, Yols. I. to XX. 8vo.
London 1865.
Linnean Society. Transactions. Yol. XXIV. Part 3. 4to. London 1864.
Journal of Proceedings. Vol. VIII. Zoology, Nos. 29 & 30 ;
Botany, Nos. 29-32, & Yol. IX. Nos. 33 & 34. 8vo. London 1864-65.
List, 1864. 8vo.
Pathological Society. Transactions. Yol. XV. 8vo. London 1864.
A General Index to the first fifteen volumes of the
Transactions, compiled by T. Holmes. 8vo. London 1864.
Photographic Society. The Photographic Journal. Nos. 147-158. 8vo.
London 1864-65.
Boyal Agricultural Society. Journal. Yol. XXV. Part 2. Second Series,
Vol. I. Part 1. 8vo. London 1864-65.
Boyal Asiatic Society. Journal. NewSeries. Yol. I. Parti. 8vo. London 1864.
Boyal Astronomical Society. Memoirs. Yol. XXXII. 4to. London 1864.
Monthly Notices. Yol. XXIV. No. 9 ; Yol.
XXV. Nos. 1—7. 8vo. London 1864-65.
Boyal Geographical Society. Journal. Yols. XXXIII. & XXXIV. 8vo.
London 1863-64.
Proceedings. Yol. VIII. Nos. 4-6 ; Yol. IX.
Nos. 1 & 2. 8vo. London 1864-65.
Boyal Horticultural Society. Proceedings. Vol. IY. Nos. 10-12 ; Vol. V.
Nos. 1-6. 8vo. London 1864-65.
Donors.
The Society.
The Geological Survey Office.
The Institution.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
The Society.
[ 7 ]
Donors.
Presents.
ACADEMIES and SOCIETIES ( continued ).
London : —
Royal Institute of British. Architects. Sessional Papers, 1864-65. Part I.
Hos. 1-4 ; Part 2. Nos. 1-6 ; Part 3. Nos. 1-3 & 5. 4to. London 1865.
Royal Institution. Proceedings. Yol. IY. Parts 3 & 4. 8vo. London 1864.
Royal Medical and Chirurgical Society. Medico-Chirurgical Transactions.
Yol. XLVII. 8vo. London 1864.
Proceedings. Yol. IY. Nos. 5 & 6;
Yol. Y. No. 1. 8vo. London 1864-65.
Index to the Catalogue of the
Library. 8vo. London 1860.
Royal Society of Literature. Transactions. Second series. Yol. YIII.
Part 1. 8vo. London 1864.
Annual Report ; the President’s Address ;
List of Members, 1864. 8vo. London.
Royal United Service Institution. Journal. Yol. YIII. Nos. 31-33, and
Appendix. 8vo. London 1864-65.
Society for the Suppression of Mendicity. Forty-sixth Report. 8vo.
London 1864.
Society of Antiquaries. Proceedings. Second series. Yol. II. Nos. 4 & 5.
8vo. London 1863.
Zoological Society. Transactions. Yol. Y. Parts 1-3. 4vo. London
1862-64.
Proceedings of the Scientific Meetings, for 1863.
3 parts. 8vo. London.
Luxembourg : — Societe des Sciences Naturelles. Tome YII. 8vo. Luxembourg
1864.
Madrid: — Memorias de la Real Academia de Ciencias. la serie: Ciencias
Exactas. Tomo I. parte 2. 2a serie : Ciencias Eisicas. Tomo I. parte 3 ;
Tomo II. parte 1. 8vo. Madrid 1863-64.
Mantua: — Accademia di Scienze, Belle Lettere ed Arti. Anno 1864. 8vo.
Mantova.
Mauritius : — Meteorological Society. Proceedings and Transactions. Yol. YI.
8vo. Mauritius 1864.
Milan : —
Memorie del Reale Istituto Lombardo di Scienze, Lettere ed Arti. Yol. IX.
fasc. 2 & 4. 4to. Milano 1862-63.
Atti. Yol. III. fasc. 58, 15 & 16. 4to. Milano 1862-63.
Anuario, 1864. 8vo. Milano.
Rendiconti. Classe di Scienze Matematiche e Naturali : Yol. I. fasc. 4-7.
Classe di Lettere e Scienze Morali e Politiche : Yol. I. fasc. 3-7. 8vo.
Milano, 1864.
Atti della fondazione scientifica Cagnola dalla sua istituzione in poi. Yol.
III. 8 vo. Milano 1862.
Atti della Societa Italiana di Scienze Naturali. Yol. Y. fasc. 4 & 5 ; Yol. YI.
fasc. 1-3. 8vo. Milano 1863-64.
Modena: — Memorie della Societa Italiana delle Scienze. Serie seconda.
Tomo I. 4to. Modena 1862,
The Institute.
The Institution.
The Society.
The Society.
The Institution.
The Society.
The Society.
The Society.
The Society.
The Academy.
The Academy.
The Society.
The Institute.
The Society.
The Society.
The Society.
[ 8 ]
Donors,
Presents,
ACADEMIES and SOCIETIES ( continued ).
Montpellier : — Memoires de l’Academie des Sciences et Lettres. Section des
Sciences : Tome V. Section de Medecine : Tome III, fasc. 4 & 5 ; Tome
IY. fasc. 1. Section des Lettres : Tome III. fasc. 3 & 4. 4to. Montpellier
1861-63.
Montreal: — The Canadian Naturalist and Geologist. New Series. Yol. I.
Nos. 1-6. 8vo. Montreal 1864.
Moscow: — Bulletin de la Societe Imperiale des Naturalistes. Annee 1863,
Nos. 1-4; 1864, No. 1. 8vo. Moscou 1863-64.
Munich : —
Sitzungsberichte der konigl. bayer. Akademie der Wissenschaften, 1864.
I. Hefte 3-5 ; II. Hefte 1-4. 8vo. Munchen 1864.
Gelehrte Anzeigen. Bande I.-Y. 4to. Munchen 1835-37.
Ueber den Begriff der biirgerlichen Gesellschaft. Yortrag von W. H. Riehl.
4to. Munchen 1864.
Konig Maximilian II. und die Wissenschaft. Rede von J. v. Dollinger. 8vo.
Munchen 1864.
Chinesische Texte zu Dr. J. H. Plath’s Abhandlung : Abtheilung II. Der
Cultus der alten Chinesen. 4to. Munchen 1864.
Die Stellung Yenedigs in der Weltgeschichte : Rede von G. M. Thomas. 4to.
Munchen 1864.
Naples: —
Societa Reale. Atti dell’ Accademia delle Scienze Eisiche e Matematiche.
Tomo I., Anno III. fasc. 1-6. 4to. Napoli 1863-64.
Rendiconto: Anno II. fasc. 4-12; Anno III. fasc. 1&2, 1863
-64. Rendiconto delle tornate e dei lavori dell’ Accademia di Scienze
Morali e Politiche : Anno II. Aprile-Dicembre 1863; Anno III. Maggio-
Dicembre 1864 ; Anno IY. Gennaio 1865. Rendiconto della Reale Acca-
demia di Archeologia, Lettere e Belle Arti : Anno 1863 ; Anno 1864,
Gennaio-Giugno. 4to. Napoli 1863-65. Annuario 1865.
Neuchatel: — Bulletin de la Societe des Sciences Naturelles. Tome YI.
troisieme cahier. 8vo. Neuchdtel 1864.
Newcastle-upon-Tyne : — Tyneside Naturalists’ Field Club. Transactions. Yol.
YI. Part 2. 8vo. Newcastle 1864.
Paris : —
Comptes Rendus Hebdomadaires des Seances de l’Academie des Sciences.
June to December 1864, January to June 1865. Tome LIX. Table de
Matieres. 4to. Paris 1864-65.
Connaissance des Temps pour l’an 1866, publie par le Bureau des Longi-
tudes. 8vo. Paris 1864.
Annuaire pour l’an 1865. 12mo. Paris.
Depot de la Marine. Annales Hydrographiques. 2e-4® trimestre de 1863 ;
lr trimestre de 1864. 8vo. Paris.
Annuaire des Marees des Cotes de France pour 1865.
12mo. Paris 1863.
Instructions Nautiques sur les cotes est de la Chine,
&c., traduites sur la derniere edition du China Pilot, par M. de Yautre.
8vo. Paris 1863.
The Academy.
The Natural History So-
ciety.
The Society.
The Academy.
The Society.
The Society.
The Club.
The Institute.
The Bureau.
The Depot de la Marine.
[ 9 ]
Presents.
ACADEMIES and SOCIETIES {continued).
Paris : —
Depot de la Marine. Pilote de Pile Guernesey, traduit par M. jMassias.
8vo. Paris 1864.
Instructions Nautiques sur les cotes de la Patagonie,
par Paul Martin. 8vo. Paris 1863.
Pilote de Pile Vancouver, par G. H. Richards, traduit
par H. Perigot. 8vo. Paris 1863.
Formule generale pour trouver la Latitude et la Lon-
gitude, par L. Pagel. 8vo. Paris 1863.
Instructions Nautiques sur la Mer Baltique et le Golfe
de Einlande, par A. Le Gras. Tome I. 8vo. Paris 1864.
Les cotes du Bresil, Description et Instructions Nau-
tiques, par Ernest Mouchez. IIe section. 8vo. Paris 1864.
Maps and Charts.
Annales des Mines. 6e serie. 2e-6e liv. de 1864 ; leliv. de 1865. 8vo. Paris.
Annuaire de ITnstitut des Provinces, des Societes Savantes et des Congres
Scientifiques. 2e serie. Vol. VI. 8vo. Paris 1864.
Bulletin International de l’Ohservatoire Imperial. June 11 to December 31,
1864 ; January 1 to June 14, 1865. folio. Paris.
Comptes Rendus des Seances et Memoires de la Societe de Biologie. 3e serie.
Tome V. Annee 1863. 8vo. Paris 1864.
Bulletin de la Societe d’Encouragement pour l’lndustrie Rationale. 2e serie.
Tome XI. January to December 1864; Tome XII. January to April 1865.
4to. Paris.
Bulletin de la Societe de Geographie. 5e serie. Tome VII. 8vo. Paris 1864.
Bulletin de la Societe Geologique. 2e serie. Tome XXII. feuilles 1-7. 8vo.
Paris 1864.
Penzance : — Royal Geological Society of Cornwall. Forty-sixth and Forty-
seventh Annual Reports. 8vo. Penzance 1860.
Philadelphia : —
Academy of Natural Sciences. Proceedings. 1864. Nos. 1-5. 8vo. Phi-
ladelphia.
Franklin Institute. Journal. Nos. 461-472. 8vo. Philadelphia 1864-65.
Charter and By-Laws. 8vo. Philadelphia 1864.
Rome : — ■
Atti dell’ Accademia Pontificia de’ Nuovi Lincei. Anno XVII. Sess. 1-7.
4to. Roma 1864.
Bullettino Meteorologico dell’ Osservatorio del Collegio Romano, compilato
dal P. Angelo Secchi. Vol. II. No. 12 ; Vol. III. Nos. 5, 6, 8, 10-13 ;
Vol. IV. Nos. 1, 2 & 4. 4to. Roma 1863-65.
Memorie dell’ Osservatorio del Collegio Romano. Nuova serie. Vol. II.
4to. Rama 1863.
Rouen : — Congres Scientifique de France. 32e session. Rouen. 31 Juillet
1865. 4to. Rouen.
St. Petersburg: —
Memoires de l’Academie Imperiale des Sciences. Tome V. Nos. 1-9 ; Tome
VL. Nos. 1—12. 4to. St. Petersbourg 1862—63.
MDCCCLXV. b
Donoks.
The Depot de la Marine.
L’Ecole des Mines.
The Institute.
The Observatory.
The Society.
The Society.
The Society.
The Society.
The Society.
The Academy.
The Institute.
The Academy.
The Observatory.
The College.
The Congress.
The Academy.
[ 10 ]
Donors.
Presents.
ACADEMIES and SOCIETIES ( continued ).
St. Petersburg: —
Memoires del’Academie Imperiale des Sciences. Bulletin. TomeY. Nos. 3-8;
Tome YI. Nos. 1-5 ; Tome 7. Nos. 1 & 2. 4to. St. Petersbourg 1863.
Annales de l’Observatoire Physique Central de Eussie, par A. T. Kupffer.
Annees 1860 & 1861. 4to. St. Petersbourg 1863.
Comptes Rendus Annnels. Annees 1861, 1862 & 1863. 4to. St. Petersbourg
1862- 64.
Considerations sur la prevision des tempetes et specialement sur eelles An 1
au 4 Decembre 1863. 4to. St. Petersbourg 1864.
Horae Societatis Entomologicae Rossicse, Fasciculus 1. 8vo. Petropoli 1861.
Stockholm : —
Kongliga Svenska Yetenskaps-Akademiens Handlingar. Ny Foljd. Bandet
IY. Haftet 2. 4to. Stockholm 1862.
Ofversigt af . . . Forhandlingar. Argangen XX. 8vo. Stockholm 1864.
Meteorologiska Jakttagelser i Sverige. Bandet IY. 4to. Stockholm 1862.
Toronto : —
The Canadian Journal of Industry, Science, and Art. New series. Nos. 52-56.
8vo, Toronto 1864-65.
Abstracts of Meteorological Observations made at the Magnetical Obsexva--
tory, 1854-59, 1860-62. 2 vols. 4to. Toronto 1864.
Toulouse : — Memoires de l’Academie Imperiale des Sciences, Inscriptions et
Belles-Lettres. 6e serie, Tome II, 8vo. Toulouse 1864.
TJpsala: —
Universitets Arskrift, 1863. 8vo. Upsala.
Nova Acta Begiae Societatis Scientiarum Upsaliensis, Seriei tertige. YqI. Y,
fasc. 1. 4to. TJpsalice 1864,
Befractors-Beobachtungen der X. Universitats-Sternwarte in Upsala vom
Feb. 1862 bis Jan. 1864, 8vo. Upsala 1864.
Utrecht: — Meteorologische Waarnemingen in Nederland en zijne Bezittin-
gen, door het Koninklijk Nederlandsch Meteorologisch Instituut, 1863.
(2 copies.) 4to. Utrecht 1864.
Yenice : —
Atti dell’ Ateneo Yeneto. Serie 2, Yol. I. puntata 1. 8vo. Venezia 1864.
Memorie dell’ I. B. Istituto Yeneto di Scienze, Lettere ed Arti. YoL II.
parte la e 2a. 4to. Venezia 1862-64.
Atti. Serie terza. Tomo IX. disp, 1-10 ; Tomo X. disp, 1-4. 8vo. Venezia
1863- 65.
Yienna : — -
Denkschriften der kaiserlichen Akademie der AVissenschaften. Math.-
Naturw. Classe : Bande XXII. & XXIII. Phil. -Hist. Classe : Band
XIII. 4to. Wien 1864,
Sitzungsberichte. Math. -Nat. Classe. Band XLYII. Abth. 2. Heft 5;
Band XLYIII. Abth. 1, Hefte 1-5, Abth. 2. Hefte 1-5 ; Band XLIX.
Abth. 2. Hefte 1-5 ; Band L. Abth. 1. Hefte 1. 8vo. Wien 1863-64.
Phil.-Hist. Classe. Band XLII. Hefte 1-3 ; Band XLIII.
Hefte 1 & 2; Band XLIY, Hefte 1-3; Band XLY. Hefte 1-3; Band
XLYI. Hefte 1-3. 8vo. Wien 1863-64.
The Academy.
TheAdministration of Mines.
The Linnean Society.
The Academy.
The Canadian Institute.
The Observatory.
The Academy.
The University.
The Society.
The Observatory.
The Institute.
The Athenseum.
The Institute.
The Academy.
The Academy.
t 11 ]
Peesents.
ACADEMIES and SOCIETIES (continued).
Vienna : —
Anzeiger. Math.-Haturw. Classe. 1. Jahrgang, 1864, Hr. 14-28 ; 1865,
Hr. 1-14. 8 vo. Wien 1864—65.
Almanach, Jahrgang 13 & 14. 1863, 1864. 8vo. Wien.
Tabulae Codicum Manu Scriptorum praeter Grsecos et Orientales in Biblio-
theca Palatina Vindobonensi asservatorum : edidit Academia Caesarea Vin-
dobonensis. Vol. I. 8vo. Vindobonce 1864.
Mifctheilungen der k.-k. geographischen Gesellschaft. VII. Jahrgang, 1863.
8vo. Wien.
Jahrbuch der k.-k. geologischen Reichsanstalt. B. XIII. Hr. 4 ; B. XIV.
Hr. 2, 3 & 4. 8vo. Wien 1863-64.
Bericht iiber die Erhebuugen der Wasser-Versorgungs-Commission des Ge-
meinderathes der Stadt Wien. I. Text 4to. II. Atlas in case. Wien 1864.
Washington : —
Report of the Commissioner of Patents for the Year 1861. Arts and Manu-
factures. 2 vols. 8vo. Washington 1863.
Smithsonian Contributions to Knowledge. Vol. XIII. 4to. Washington
1864.
Smithsonian Miscellaneous Collections. Vol. V. 8vo. Washington 1864.
Wurzburg: —
Physikaliseh-medicinische Gesellschaft. Wiirzburger naturwissenschaftliche
Zeitschrift. Band IV. Hefte 2 & 3 ; Band V. Hefte 1-4. 8vo. Wurzburg
1863-64.
Wiirzburger medicinische Zeitschrift. Band V. Hefte 2-6. 8vo. Wurzburg
1864.
Zurich : —
Vierteljahrsschrift der naturforschenden Gesellschaft. Jahrgang 7. Hefte
3 & 4; Jahrg. 8. Hefte 1-4. 8vo. Zurich 1862-63.
An die Ziircherische Jugend auf die Jahre 1863, 1864. 4to Zurich.
Houveaux Memoires de la Societe Helvetique des Sciences Haturelles. Band
XX. 4to. Zurich 1864.
ADOLPH (W.) The Simplicity of the Creation, or the Astronomical Monument
of the Blessed Virgin, a Hew Theory of the Solar System. 8vo. London
1864.
AIRY (G. B., E.R.S.) Astronomical, Magnetical, and Meteorological Obser-
vations made at the Royal Observatory, Greenwich, in 1862. 4to. London
1864.
— ■ — Seven-Year Catalogue of 2022 Stars, deduced from
Observations extending from 1854 to 1860. 4to. London 1862.
Plan of the Buildings and Grounds of the Royal Obser-
vatory, Greenwich. 4to. London 1863.
■ - Determination of the Longitude of Valentia in Ireland,
by Galvanic Signals, in 1862. 4to. London.
AKIH (Dr. C. K.) On the Transmutation of Spectral Rays. Part 1. (Excerpt
from Brit. Assoc. Rep.) 8vo. London 1863.
— On the Origin of Electricity. (Excerpt from Trans. Camb.
Phil. Soc.) 4to. Cambridge 1865.
b 2
Donoes.
The Academy.
The Society.
The Institute.
Sir Charles Lyell, Bart.,
F.R.S.
The Patent-Office, Washing-
ton.
The Smithsonian Institu-
tion.
The Society.
The Society.
The Society.
The Author.
The Lords Commissioners
of the Admiralty.
The Author.
[ 12 ]
Presents.
ALFONSO X. DE CASTILLA. Libros del Saber de Astronomia, copilados,
anotados y comentados por Manuel Rico y Sinobas. 2 vols. fol. Madrid
1863.
ANDREW (J. A.) Address to the Legislature of Massachusetts. 8vo. Rosfonl864.
ANONYMOUS:—
Account of several New Inventions and Improvements now necessary for Eng-
land. London 1691. — The New Invention of Mill’d Lead. London 1691.
In 1 vol. 12mo.
American Ephemeris and Nautical Almanac for 1865. 8vo. Washington
1863.
Army Lists of the Roundheads and Cavaliers, containing the Names of the
Officers in the Royal and Parliamentary Armies of 1642. Edited by
Edward Peacock. 4to. London 1863.
Army Medical Department. Statistical, Sanitary, and Medical Reports for
1862. 8vo. London 1864.
Aspects of Nature, and their Teachings. 8vo. 1864.
Calendar of the M'Gill College and University, Montreal. 8vo. Montreal 1864.
Catalogue of Additions to the Manuscripts in the Eritish Museum in the years
1846-47. 8vo. London 1864.
Catalogue of Autograph Letters forming part of the Collection of a Member of
the Incorporated Law Society. 4to. London 1862.
Catalogue of the Library of H.R.H. the Princess Elizabeth, Landgravine of
Hesse Homburg. 8vo. London 1863.
Catalogue of the Melbourne Public Library. 8vo. Melbourne 1861.
Certain Necessary Directions, as well for the Cure of the Plague as for pre-
venting the Infection. 4to. London 1665.
Companion (A) to Ragland Castle. 4to. Monmouth 1833.
Constitutions of the Musseum Minervse. 4to. London 1636.
Des erofneten Ritter Platz anderer Theil. 8vo. Hamburg 1704.
Description d’un Appareil destine a reproduire les Aurores Polaires et les phe-
nomenes qui les accompagnent. 8vo. Paris.
Descriptive Catalogue of the ‘Pathological Specimens in the Museum of the
Royal College of Surgeons. Supplement II. 4to. London 1864.
Descriptive Inventory of James Cox’s Museum. 4to. London 1774.
Discourse of the Necessity of encouraging Mechanick Industry. 4to. London
1690.
English Life Table. Tables of Lifetimes, Annuities, and Premiums, with an
Introduction by W. Earr, M.D., F.R.S. 8vo. London 1864.
Entomologist’s Annual for 1865. 12mo. London 1865.
First Biennial Report of the Progress of the Geological Survey of Michigan.
8vo. Lansing 1861.
General Description of Sir John Soane’s Museum. 12mo. London.
Humane Industry; or a History of most Manual Arts. 8vo. London 1661.
Introductory Report of the Commissioner of Patents for 1863. 8vo. Wash-
ington.
London University Calendar, 1865. 8vo.
London’s Dreadful Yisitation, or a Collection of all the Bills of Mortality for
this present year. 4to. London 1665.
Donors.
The Royal Academy of
Madrid.
The Legislature.
H. Dircks, Esq.
The Secretary of the United
States Navy.
H. Dircks, Esq.
The Director-General.
The Author.
The University.
The British Museum.
H. Dircks, Esq.
The Library.
H. Dircks, Esq.
The Author.
The College.
H. Dircks, Esq.
The Registrar-General.
H. T. Stainton, Esq.
A. Winchell, Esq.
The Trustees.
H. Dircks, Esq.
The Commissioner.
The University.
H. Dircks, Esq.
[ 13 ]
Donors.
Presents.
ANONYMOUS ( continued ).
Magnum in Parvo, or the Practice of Geometry, by E. P. 8vo. London 1671.
Mercury; or the Secret and Swift Messenger. 8vo. London 1641.
New Touch-stone for Gold and SilverWares. 8vo. London 1679.
Notice sur les Observations Meteorologiques faites dans les Pays Bas et dans
ses possessions aux Indes Orientates et Oecidentales. 8vo. Utrecht 1858.
Observations Meteorologiques faites a Nijne-Taguilsk, annee 1868. 8vo. Paris
1864.
Pleasant and Compendious History of the first Inventers and Institutes of
the most famous Arts, Misteries, Laws, Customs, and Manners in the Whole
World. 12mo. London 1686.
Eeise der osterreichischen Fregatte Novara um die Erde. Geologiseher Theil.
Band I. 4to. Wien 1864.
Statistisch-commer-
cieller Theil, von X. von Scherzer. Band I. 4to. Wien 1864.
Eeport of the Superintendent of the Coast Survey, showing the Progress of the
Survey during 1861. 4to. Washington 1862.
Salomons Pest-House, or Towre Boyall, newly re-edified and prepared to pre-
serve Londoners from the Plague. 4to. London 1630.
Shutting (The) up of Infected Houses, as it is practised in England, soberly
debated. 4to. London 1665.
South (The) Sea Bubble, and the numerous fraudulent projects to which it
gave rise in 1720. 12mo. London 1825.
Statistique de la France. — Prix et Salaires a diverses epoques. Deuxieme serie.
Tome XII. 4to. Strasbourg 1863.
Sveriges Geologiska Undersokning pa offentlig bekostnad utford, under led-
ning af A. Erdmann. Parts 6-13. 8vo. Stockholm 1863-64.
Third Eeport of the Commission appointed to inquire into the best mode of
distributing the Sewage of Towns. 8vo. London 1865.
Transactions and Eeports of the Special Committee on Iron, between 21st
January 1861 and March 1862. 1862-63. 3 vols. folio. Photographs to
accompany the Eeports, in 6 vols. oblong.
Treasure of Evonymus, conteyninge the WonderfuE hid Secretes of Nature,
touchinge the most apte formes to prepare and destyl Medicines, for the
conservation of helth, translated by P. Morwing. 4to. London 1559.
True and Faithful Account of the several Informations exhibited to the Com-
mittee appointed by the Parliament to inquire into the late dreadful burn-
ing of the City of London. 4to. 1667.
Twenty-eighth Annual Eeport of the Council of the Art-Union of London.
8vo. London 1864.
Weekly Eeturns of Births and Deaths in the City of Dublin. Yol. I. 1864,
Nos. 1-52 (wanting No. 29); Yol. II. 1865, Nos. 1-23. Quarterly Ee-
turns of Births and Deaths, 1864, Nos. 1 & 2. 8vo. Dublin 1864-65.
Witty Apophthegms, delivered at several times and upon several occasions
by Xing James, King Charls, the Marquess of Worcester, Lord Bacon, and
Sir Thomas Moor. 12mo. London 1669.
AEGYLL (Duke of, F.E.S.) Address to the Eoyal Society of Edinburgh,
5th December, 1864. 8vo. Edinburgh 1864.
H. Dircks, Esq.
The Meteorological Insti-
tute, Utrecht.
The Prince Demidoff.
H. Dircks, Esq.
Dr. F. von Hochstetter.
Dr. von Scherzer.
The Survey.
H. Dircks, Esq.
Unknown.
The Geological Board of
Sweden.
J. B. Lawes, F.E.S.
The Lords Commissioners of
the Admiralty.
H. Dircks, Esq.
The Art-Union.
The Eegistrar-General, Ire-
land.
H. Dircks, Esq.
The Author.
[ 14 ]
Presents.
BABBAGE (C., F.E.S.) Passages from the Life of a Philosopher. 8vo. London
1864.
BACHE (A. D.) Eecords and Eesults of a Magnetic Survey of Pennsylvania
and Parts of adjacent States. (Excerpt from Smithsonian Oontrib.) 4to.
Washington 1863.
BACON (Francis) The Wisedome of the Ancients, done into English by Sir A.
Gorges. 12mo, London 1619.
BAKEE (T.) The Steam-Engine, or the Powers of Flame : an Original Poem.
8vo. London 1857.
BAEBEE (J. T.) A Tour through South Wales and Monmouthshire. 8vo. Lon-
don 1803.
BATE (J.) The Mysteries of Nature and Art, in foure severall parts, the
second edition. (The Booke of Extravagants.) 4to. London 1635.
BAYLY (T.) Herba Parietis, or the Wall-Flower : a History which is partly
true, partly romantick, morally divine, folio. London 1650.
The Golden Apophthegms of his Eoyall Majesty King Charles I.
and Henry Marq. of Worcester. 4to. London 1660.
BEATTIE (W.) Eaglan Castle. 8vo. London.
BECHI (E.) I Soffioni Boraciferi diTriavale. Memoria letta alia Eeale Acca-
demia dei Georgofili. 8vo. 1863.
BELAYENETZ (Captain) Blank Forms for the Computation of the Deviations -
and Magnetic Observations on Board of Ship, 8vo. St. Petersbourg
1864.
On the Magnetic Condition of the Iron-clad ‘Perve*
netz.’ 8vo. St. Petersbourg 1865.
BELLET (L.) et EOUVEE (C. de) Notice sur le nouveau systeme de Loco-
motive Electro-Magnetique. 8vo. Paris 1864.
BENSON (L. S.) Argumentum ad Hominem. Geometrical Disquisitions. 8vo.
London 1864.
BESSONI (J.) II Theatro de gl’ Instrumenti & Machine. foL Lione 1582.
[BIECH (T.)] An Inquiry into the share which K. Charles I. had in the
Transactions of the Earl of Glamorgan, for bringing over a body of Irish
Eebels to assist that King in 1645 and 1646. 8vo. London 1747. Second
edition, 8vo. London 1756.
BOATE (G.) Irelands Naturall History, now published by S'. Hartlib. 8vo.
London 1652.
BOHM (J. G.) und ALLE (M.) Magnetische und meteorologische Beobach-
tungen zu Prag. Jahrgang 25. 4to. Prag 1865.
BOND (H.) The Longitude Found, or a Treatise shewing an easie and speedy
way to find the Longitude. 4to. London 1676.
[BOSWELL (Eev. J.)] The Case of the Eoyal Martyr considered with candour.
2 vols. 8vo. London 1758.
BOUDIN (J. C. M.) Etudes Anthropologiques : Considerations sur le culte et
les pratiques religieuses de divers peuples anciens et modernes : Culte de
Phallus ; Culte du Serpent, 8vo. Paris 1864.
BOUTON (L.) Plantes Medicinales de Maurice. 8vo. Port Louis 1864.
BEAYLEY (E. W., F.E.S.) Physical Constitution of the Sun. No. 2. 12mo.
London 1865.
Donors.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Author.
Mons. L. Bellet.
The Author.
H. Dircks, Esq.
The Observatory.
H. Dircks, Esq.
G. Witt, F.E.S,
The Author.
The Author.
[ 15 ]
Pkesents.
BRODIE (Sir B. C., F.R.S.) Works, with an Autobiography, collected and
arranged by Charles Hawkins. 3 vols. 8vo. London 1865.
BROWN (J.) The Description and XJse of a Joynt-Rule. 12mo. London 1661.
The Triangular Quadrant. 12mo. London 1662.
BURT (T. S., F.R.S.) Miscellaneous Papers on Scientific Subjects. Yol. III.
Part 2. 8vo. London 1865.
CALYERT (F.) Contributions towards the Ancient Geography of the Troad :
On the site of Gergis. 8vo.
CAPRA (A.) La Nuova Architettura Famigliare. 4to. Bologna 1678.
CAUTLEY (Colonel Sir Proby T., F.R.S.) Ganges Canal : a Valedictory Note
to Sir Arthur Cotton. 8yo. London 1864.
CECCHI (F.) e ANTONELLI (G.) II Barometro Areometrico a Bilancia della
Loggia dell’ Orgagna in Firenze. 8vo. Pisa 1863.
CERYO (F.) Legge per la Religione in Italia, Progetto. 8vo. Napoli 1864.
CHALLIS (Rev. J., F.R.S.) Astronomical Observations made at the Observa-
tory of Cambridge. Yol. XX. 4to. Cambridge 1864.
CHEYREUL (M. E., For. Mem. R.S.) Recherches Chimiques sur la Teinture :
douzieme a quatorzieme memoires. 4to. Paris 1863. (Two copies.)
COLDEX (C.) The Principles of Action in Matter, the Gravitation of Bodies
and the Motions of the Planets explained from those Principles. 8vo. Lon-
don 1751-
CORYISART (L.) Collection de memoires sur une fonction meconnue du Pan-
creas, la Digestion des Aliments Azotes. 8vo. Paris 1857-1863.
CRtlGER (H.) On the Meteorology of Trinidad. 8vo. London 1864.
DAUBENY (C-, F.R.S.) Essay on the Trees and Shrubs of the Ancients. 8vo.
Oxford 1865.
DAYIS (J. B.) The Neanderthal Skull i its peculiar conformation explained
anatomically. 8vo. London 1864,,
Sur les Deformations Plastiques du Crane. 8vo. Paris.
DAYY (Dr. John, F.R.S.) On some of the more important Diseases of the Army,
with Contributions to Pathology. 8vo. London 1862.
— — Physiological Researches. 8vo. London 1863.
Letters to the Editors of the Philosophical Maga-
zine, in reply to charges made by C. Babbage, Esq., against the late Sir
Humphry Davy, when President of the Royal Society. (Excerpt from Phil.
Mag.) 8vo. London 1864-65.
The same. (2 copies.)
DEAN (J.) The Gray Substance of the Medulla Oblongata and Trapezium.
Photographs. (Excerpt from Smithsonian Contributions.) 4to. Washington
1864.
DE LA RIYE (A.) Quelques considerations sur les Courants Electriques Ter-
restres. 8vo. Genbve 1865.
DESARGUES. (Euvres, reunies et analysees par M. Poudra. 2 vols. 8vo.
Paris 1864.
DIGGES (L.) A Prognostication everlastinge of righte good effecte, corrected
and augmented by T. Digges. 4to. London 1576.
Donobs.
The Editor.
H. Dircks, Esq.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Authors.
The Author.
The Syndicate of the Ob-
servatory.
The Author.
H. Dircks, Esq.
The Author.
The Scientific Association
of Trinidad.
The Author.
The Author.
The Author.
Sir James South, F.R.S.
The Author.
The Author.
The Editor.
H. Dircks, Esq.
[ W ]
Presents.
DILLON (E. W.) Physiological Researches relative to the functions of the
Cephalic Nerves. 8vo. Berne 1864.
DIRCKS (H.) A Biographical Memoir of Samuel Hartlib, Milton’s familiar
friend, with Bibliographical Notices of Works published by him, and a re-
print of his pamphlet entitled “ An Invention of Engines of Motion.” 8vo.
London 1865.
The Life, Times, and Scientific Labours of the second Marquis
of Worcester, to which is added a reprint of his Century of Inventions, 1663,
with a Commentary thereon. 8vo. London 1865.
DOYE (H. W., Eor. Mem. R.S.) Darstellung der Warmeerscheinungen durch
fiinftagige Mittel. Theil II. 4to. Berlin 1863.
Die Witterungserscheinungen des nordlichen
Deutschlands im Zeitraum von 1858-1863. (Preussische Statistik, YI.)
4to. Berlin 1864.
DOYNE (W. T.) Report upon the Plains and Rivers of Canterbury, New
Zealand, folio. Christchurch 1864.
DUHAMEL (J. M. C.) Des Methodes dans les Sciences de Raisonnement. 8vo.
Paris 1865.
DUTOIT (Eug.) Die Ovariotomie in England, Deutschland und Frankreich.
8vo. Wurzburg 1864.
[DYMOCK (Cressy)] An Invention of Engines of Motion lately brought to
perfection. 4to. London 1651.
EDWARDS (G. N.) and WILLETT (A.) Statistical Tables of the Patients
under treatment in the Wards of St. Bartholomew’s Hospital during 1864.
8vo. London 1865.
ELGAR (J.) Hemerologium, or Diary for Nineteen Years : MS., 1750. J. New-
ton, Tabulae Mathematicae, 1654, &c. In 1 vol. 12mo.
ELIE DE BEAUMONT (L., For. Mem. R.S.) Tableau des Donnees Nume-
riques qui fixent 159 cercles du Reseau Pentagonal. 4to. Paris 1863.
Tableau des Donnees Nume-
riques qui fixent les 362 points principaux du Reseau Pentagonal. 4to.
Paris 1864. ,
ELLIS (H. S.) On the Oyster ( Ostrea edulis ) in the West of England. 8vo.
London 1865;
ESCHER (P.) Elementare Theorie der Differenzen Briggischer und trigono-
metrischer Logarithmen. 4to. Wien 1864.
EUDES-DESLONGCHAMPS (E.) Etudes Critiques sur les Braehiopodes Nou-
veaux ou peu eonnus. Fasc. 3. 8vo. Cam 1863.
Documents sur la Geologie de la Nouvelle-
Caledonie. 8vo. Caen 1864.
£tudes sur les Etages Jurassiques Infe-
rieurs de la Normandie. 4to. Paris 1864.
Recherches sur l’Organisation du Manteau
chez les Braehiopodes Articules et principalement sur les spicules calcaires
contenus dans son interieur. 4to. Paris 1864.
EYANS (F. J., F.R.S.) and SMITH (A., F.R.S.) Ueber die Deviationen des
Compasses. Nach dem Englischen, von Dr. F. Schaub. 8vo. Wien 1864.
Donors.
The Author.
The Author.
The Author.
The Author.
The Author.
The Author.
H. Dircks, Esq.
The Hospital.
H. Dircks, Esq.
The Author.
The Author.
The Author.
The Author.
The Translator.
[ 17 j
Presents.
EYEREST (Sir G., E.R.S.) Tables for the use of the Great Trigonometrical
Survey. MS. 4to.
EWBANK (T.) A Descriptive and Historical Account of Hydraulic and other
Machines for raising Water, Ancient and Modern. 8vo. New Yorlc 1854.
FALCONER (J.) Cryptomenysis Patefacta: or the Art of secret Information
disclosed without a Key. 8vo. London 1685.
EIGUIER (L.) Exposition et Histoire des principals Decouvertes Scientifiques
modemes. 4 vols. 8vo. Paris 1862.
FLOWER (W. H., F.R.S.) Annual Report of the Conservator of the Royal
College of Surgeons to the Museum Committee, 1865. 8vo. London.
FOSBROKE (Rev. T. D.) A Picturesque and Topographical Account of Raglan
Castle. 8vo. Monmouth 1831.
FOX (F. and C.) Report respecting the past and present state of Brislington
House, near Bristol, a private Asylum for the Insane. 8vo. Bristol.
FRENCH (J.) The Art of Distillation. Second edition. 4to. London 1653.
FRITZSCHE (J.) TJeber den Pollen. 4to. St. Petersburg 1837.
A Series of Thirty Tracts on Chemistry &c. 8vo. St. Peters-
burg 1839-64.
GAFFAREL (J.) Unheard-of Curiosities, concerning the Talismanical Sculpture
of the Persians, the Horoscope of the Patriarkes, and the Reading of the
Stars. Englished by E. Chilmead. 8vo. London 1650.
GALILEO (Galilei) Opere ; prima edizione completa condotta sugli autentici
Manoscritti Palatini. 15 volumes in 16, and Supplemento. 8vo. Firenze
1842-1856.
GARRIGOU (F.) Lettre a M. le professeur N. Joly. 8vo. Toulouse 1862.
L’Homme Fossile des Cavernes de Lombrive et de Lherm
(Ariege). 8vo. Toulouse 1862.
Etude Chimique et Medicale des Eaux Sulfureuses d’Aix
(Ariege). 8vo. Paris 1862.
GIANELLI (G. L.) La Yaccinazione e le sue leggi in Italia, Memoria. 4to.
Milano 1864.
GLOCKER (E. F.) Zwei Karten zur geognostischen Beschreibung der Preuss.
Oberlausitz. 4to. 1857.
GOSAIN BUNWALIDAS, surnamed YALI. Goolzare Hall, or the Garden of
Divine Ecstacy. Published by Burjorjee Sorahjee Ashbumer, from the
Original Persian Work. 8vo. Bombay 1862.
GOYA (F.) Los Proverbios : Coleccion de diez y ocho laminas. oblong. Madrid
1864.
GRANT (R., F.R.S.) Report of the Professor of Astronomy in the University
of Glasgow. 8vo. Glasgow 1865.
GRAY (J. E., F.R.S.) A Second Letter to the Earl of Ellesmere, on the Manage-
ment of the Library of Printed Books in the British Museum. 8vo. London
1849.
Handbook of British Water-Weeds, or Algae. 8vo. Lon-
don 1864.
Address to the Zoological and Botanical Section of the
British Association, Bath, Sept. 15, 1864. 8vo. London 1864.
MDCCCLXY. c
Donors.
The Author.
H. Dircks, Esq.
The College.
H. Dircks, Esq.
The Authors.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
The Museum of Physical
Science and Natural His-
tory, Florence.
The Author.
The Author.
The Naturforschenden Ge-
sellschaft, Gorlitz.
The Editor.
The Academy of San Fer-
nando.
The University.
The Author.
[ 18 ]
Presents.
GROTIUS (H.) Syntagma Arateornm : Opus Poeticse et Astronomiae studiosis
utilissimum. 4to. Lagd. Bat. 1600.
GUEST (E., F.R.S.) The Invasion of Britain by Julius Caesar : a Memoir. 8vo.
London 1864.
HAIDINGER (W., For. Mem. R.S.) A Series of Thirty-three Papers on Me-
teoric Subjects. 8vo. Vienna 1859-63.
HAILES (J. D.) The Hailesian System of Astronomy. 8vo. Cambridge 1865.
HALLTWELL (J. 0., F.R.S.) Rara Mathematica, or a Collection of Treatises
on the Mathematics. 8vo. London 1839.
HAMEL (J.) England and Russia, comprising the Voyages of J. Tradescant
the Elder, Sir H. Willoughby, R. Chancellor Nelson, and others to the
White Sea. Translated by J. S. Leigh. 8vo. London 1854.
HANNON. The Periplus of Hannon, King of the Karchedonians, concerning
the Lyhian parts of the Earth beyond the Pillars of Herakles. 4to. London
1864.
HARTLIB (S.) A Discours of Husbandrie used in Brabant and Flanders. 4to.
London 1605 [1650].
His Legacie, or an Enlargement of the Discourse of Hus-
bandry used in Brabant and Flaunders. 4to. London 1651.
• His Legacy of Husbandry. 4to. London 1655.
An Essay for Advancement of Husbandry-Learning. 4to.
London 1651.
The Reformed Husband-man. 4to. London 1651.
■ - — A Designe for Plentie, by an Universal! planting of Fruit-
Trees. 4to. London.
HARTNUP (J) Report of the Astronomer to the Marine Committee, Mersey
Docks and Harbour Board. 8vo. Liverpool 1864.
HEATH (C.) Historical and Descriptive Accounts of the ancient and present
state of Ragland Castle. 8vo. Monmouth 1825.
HELMHOLTZ (H., For. Mem. R.S.) Die Lehre von den Tonempfindungen als
physiologische Grundlage fiir die Theorie der Musik : zweite Ausgabe. 8vo.
Braunschweig 1865.
HERICOURT (Comte Achmet d’) Annuaire des Societes Savantes de la France
et de l’Etranger. 2 vols. in 1. 8vo. Paris 1863-64.
— Tome II. 8vo. Paris 1864.
HERMITE ( — ) Sur les Theoremes de M. Kronecker relatifs aux formes qua-
dratiques. 4to. Paris 1862.
Sur un nouveau Developpement en serie des Fonctions. 4to.
Paris 1864.
Remarque sur le developpement de cos am x. 4to. Paris
1864.
HERO Alexandrinus. Spiritali . . . ridotti in lingua volgare da Alessandro
Giorgi. 4to. Urbino 1592.
Gli Artificiosi e Curiosi Moti Spiritali, tradotti da
G. B. Aleotti. 4to. Bologna 1647.
— De gli Automati overo Machine se moventi libri due,
Donobs.
H. Dircks, Esq.
The Author.
The Author.
The Author.
H. Dircks, Esq.
Dr. Simonides.
H. Dircks, Esq.
The Committee.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
The Author.
The Author.
H. Dircks, Esq.
tradotti da B. Baldi. 4to. Venetia 1589.
[ 19 ]
Presents.
HERO Alexandrinus. Buch von Lufft- nnd Wasser-Kiinsten, aus dem La-
teinischen ins Teutsehe gebracht durch A. Carionem. 4to. Franckfurt
1688.
HERSCHEL (A. S.) On the Detonating Meteor of December 5, 1863. 8vo.
Manchester 1864.
and GREG (R. P.) General Radiant-Points of Shooting
Stars. (Excerpt from Proc. Brit. Meteor. Soc.) 8vo. London 1865.
HODY (Baron de) Godefroid de Bouillon a Boulogne-sur-Mer, a Bruxelles, et
a Jerusalem! 8vo. Bruocelles 1863.
HOEK (M.) Recherches Astronomiques de l’Observatoire d’Utrecht. /Liv. II.
4to. La Haye 1864.
et OUDEMANS (A. C.) Recherches sur la quantite d’ ether eon-
tenue dans les liquides. 4to. La Haye 1864.
Sur les Contractions dans les Melanges
de Liquides. 4to. La Haye 1864.
HORATIIS (C. de) Nuovi Elementi della Scienza Acustico-Musicale applicabili
alia Scienza delle Arti. 8vo. Napoli 1865.
HORNES (Dr. M.) Die fossilen Mollusken des Tertiar-Beckens von Wien.
Band II. Nr. 5 & 6. Bivalven. 4to. Wien 1865.
HUGHES (D. E.) Experiences sur la Forme et la Nature des Electro-Aimants.
8vo. Paris 1864.
HUGUENY (F.) Recherches experimentales sur la Durete des corps ct spe-
cialement sur celle des Metaux. 8vo. Paris 1865.
Recherches sur la composition chimique et les proprietes
qu’on doit exiger des Eaux Potables. 8vo. Paris 1865.
HUME (A.) Of the Orthographie and Congruitie of the Britan Tongue.
Edited by H. B. Wheatley. 8vo. London 1865.
ICERY (M. E.) Memoire sur le Pou a Poche Blanche. 8vo. Maurice 1864.
JACKSON (S.) An Authentick Account of the Weights, Measures, Exchanges,
Customs, Duties, Port Charges, &c., and correct Batty Tables, made use of
and paid at the several ports of the East Indies. 4to. London 1764.
JEFFREYS (J. G., F.R.S.) The Upper Tertiary Fossils at Uddevalla in Swe-
den: 1863. Report of the Committee appointed for exploring the Coasts of
Shetland by means of the Dredge. (Excerpt from Report Brit. Assoc.) 8vo.
London 1863.
JOLY (N.) Conference Publique sur l’Heterogenie ou Generation Spontanee,
28 Juin 1864. 8vo. Paris 1864.
JOUGLEZ DE LIGNE (— ) La Bade de Dunkerque. 8vo. Paris 1864.
JOURNALS : —
Cosmos. June to December 1864 ; January to June 1865. 8vo. Paris.
Giornale per l’Abolizione della Pena di Morte ; diretto da Pietro Ellero. 9-11.
8vo. Bologna 1864-65.
Les Mondes. June to December 1864; January to June 1865. 8vo. Paris.
Notes and Queries. June to December 1864; January to June 1865. 4to.
London.
The American Journal of Science and Arts. Vol. XXXVIII. Nos. 112-114;
Yol. XXXIX. Nos. 115-117. 8vo. New Haven 1864-65.
c2
Donors.
H. Dircks, Esq.
The Author.
The Authors.
The Author.
The Observatory.
The Authors.
The Author.
The Geological Institute,
Vienna.
The Author.
The Author, by R. Mallet,
F.R.S.
The Editor.
The Author.
Dr. Sharpey, Sec. R.S.
The Author.
The Author.
The Author.
The Editor.
The Editor.
The Editor.
The Editor.
The Editors.
[ 20 ]
Donors.
Presents.
JOURNALS ( continued ).
The Athenaeum. June to December 1864 : January to May 1865. Ho. London.
The Builder. June to December 1864; January to June 1865. folio. London.
The Chemical News. June to December 1864 ; January to June 1865. 4to.
London.
The Educational Times. Yol. XYII. Nos. 40-47 ; Yol. XYIII. Nos. 49-51.
4to. London 1864-65.
The Intellectual Observer. July to September 1864 ; May 1865. 8vo.
London.
The London Review. July to December 1864 ; January to June 1865. folio.
London.
The Mining and Smelting Magazine. Yol. Y. No. 30 ; Yol. YI. Nos. 31-36 ;
Yol. YII. Nos. 37 & 38. 8vo. London 1864-65.
The Philosophical Magazine. July to December 1864 ; January to June 1865.
8vo. London.
The Quarterly Journal of Science. Nos. 2-6. 8vo. London 1864-65.
The Reader. June to December 1864 ; January to June 1865. folio. London.
KOLLIKER (A., Eor. Mem. R.S.) Kurzer Bericht iiber einige im Herbst 1864
an der Westkiiste von Schottland angestellte vergleichend-anatomische Un-
tersuchungen. 8vo. Wurzburg 1864.
leones Histiologicae oder Atlas der ver-
gleichenden Gewebelehre. Abth. I. 4to. Leipzig 1864.
KOPS (J.) en HARTSEN (F. A.) Flora Batava, Afbeelding en Beschrijving
van Nederlandsche Gewassen. Afl. 187-191. 4to. Amsterdam.
LA HIRE (P. de) Traite de Mecanique. 8vo. Paris 1695.
LAMONT (Dr. J., For. Mem. R.S.) Annalen der koniglichen Sternwarte bei
Munchen. Bande XIII. & XIY. 8vo. Munchen 1864-65.
LANCIA DI BROLO (F.) Statistica dei Sordomuti di Sicilia nel 1863. 8vo.
Palermo 1864.
LA NOUE (Lord de) Politicke and Militarie Discourses, translated by E. A.
4to. London 1587.
LA WES (J. B., F.R.S.) On the Chemistry of the Feeding of Animals for the
production of Meat and Manure. 8vo. Dublin 1864.
and GILBERT (J. H., F.R.S.) Report of Experiments
on the Growth of Wheat for twenty years in succession on the same land.
8vo. London 1864.
Further Report of Ex-
periments with different Manures on Permanent Meadow Land. 8vo. London
1863.
LEIBNITII de Expeditione ^Egyptiaca Scripta Omnia, adjecta prsefatione histo-
rico-critica : edidit Onno Klopp. 8vo. Hanoverce 1864.
LEYI (Leone) Introductory Lecture on International Maritime Law. 8vo.
London 1865.
LEYI (M. R.) La Patologia Cellulare considerata nei suoi fondamenti e nelle sue
applicazioni. 8vo. Venezia 1863.
LEYBOURN (W.) Pleasure and Profit, consisting of Recreations of divers kinds,
fol. London 1694.
The Editor.
The Editor.
The Editor.
The Editor.
The Editor.
The Editor.
The Editor.
W. Francis, Esq.
The Editors.
The Editor.
The Author.
H. M. the Eing of the Ne-
therlands.
H. Dircks, Esq.
The Observatory.
The Author.
H. Dircks, Esq.
The Author.
The Authors.
The Editor.
The Author.
The Author.
H. Dircks, Esq.
[ 21 ]
Presents.
LILLY (W.) The Book of Knowledge, by Erra Pater. A rich Cabinet with
Variety of Inventions, by J. White. London 1684. 2 vols. in 1. 8vo.
LITTEOW (C. von) Annalen der k.-k. Sternwarte in Wien. Dritter Folge
zwolfter Band. Jahrgang 1862. 8vo. Wien 1863.
nnd WEISS (E.) Meteorologische Beobachtungen an der
. k.-k. Sternwarte in Wien von 1775 his 1855. Band IV. 8vo. Wien 1863.
LODGE (E.) Portraits of the Earls of Worcester, 1544-1667. 8vo.
LOWE (E. J.) Our Native Ferns. Part XX. 8vo. London 1865.
LUBBOCK (Sir J., E.E.S.) Prehistoric Times, as illustrated by Ancient Eemains
and the Manners and Customs of Modern Savages. 8vo. London 1865.
LUCAS (C.) A Treatise named Lucarsolace, divided into fower Bookes. 4to.
London 1590.
MACKENZIE (W.) Entoptics. — Letter from Dr. Jago. 8vo. Glasgow 1864.
MAGEINI (Luigi) Sulla Importanza dei Cimelj Scientifici e dei Manoscritti
di Alessandro Volta. 8vo. Milano 1864.
MAILLY (E.) Essai sur les Institutions Scientifiques de la Grande Bretagne
et de Plrlande. V. 8vo. Bruxelles 1865.
MAIN (Eev. E., E.E.S.) Astronomical and Meteorological Observations made
at the Eadcliffe Observatory in the year 1862. Vol. XXII. 8vo. Oxford
1865.
MAEEY (E. J.) Physiologie Medicale de la Circulation du Sang. 8vo. Paris
1863.
M[ABKHAM] (G.) The English Husbandman. 4to. London 1613.
The Souldiers Exercise, in three bookes. 4to. London
1639.
MAETINS (C.) Tableau Physique du Sahara Oriental de la province de Con-
stantine, Souvenirs d’un Voyage execute pendant l’hiver de 1863 dans
l’Oued-Bir et dans l’Oued-Souf. 8vo. Paris 1864.
Deux Ascensions Scientifiques au Mont-Blanc, leurs resultats
immediats pour la Meteorologie, la Physique du Globe et les Sciences Natu-
relles. 8vo. Paris 1865.
MAUMENE (E.) Theorie Geuerale de l’exercice de l’Affinite. 8vo. Paris
1864.
MAUPEETUIS (De) Lettre sur le Progres des Sciences. 8vo. 1752.
MEEHAN (Eev. C. P.) The Confederation of Kilkenny. 16mo. Dublin 1862.
MELSENS ( — .) Deuxieme Note sur les Matieres Albumino'ides. 8vo. Brux-
elles 1864.
MEEET (L. E.) De l’lnstinct et de l’lntelligence des Animaux. 8vo. Pains
1864.
MEBBIEIELD (C. W., E.E.S.) Address delivered at the opening of the Eoyal
School of Naval Architecture and Marine Engineering at South Kensington,
Nov. 1, 1864. 8vo. London 1864.
MILLEE (W. A., Treas. E.S.) Elements of Chemistry. Part 2. Inorganic
Chemistry. Third edition. 8vo. London 1864.
MILNEE (Eev. T.) The Gallery of Geography. Parts 10-19. 8vo. London
1864.
MILTON (John) Of Education. To Master S. Hartlib. 4to.
Donors.
H. Dircks, Esq.
The Observatory.
H. Dircks, Esq.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Istituto Lombardo.
The Author.
The Eadcliffe Trustees.
The Author, by Dr. Hum-
phry.
H. Dircks, Esq.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Author.
The Author.
The Author.
Messrs. Chambers.
H. Dircks, Esq.
[ 22 ]
Presents. Donors.
MIQUEL (F. A. G.) Annales Musei Botanici Lugduno-Batavi. Tom. I. fasc. The Museum.
4-10. fol. Amst. 1863-64.
MISCELLANEOUS : —
Collection of Oriental Manuscripts in the Zend, Pehlvi, and Persian Languages.
Persian Dictionary, by Abdool Rahim, 2 yols. 4to. Mahabharat, Persian Burjorjee Sorabjee Asb-
translation, fol. Amrat Hand, Persian translation from Sanscrit, 4to. burner, Esq.
Hitopodesh, Persian translation from Sanscrit, 4to. Sarod, Persian trans-
lation, 4to. The Gita, Persian translation from Sanscrit, 4to. Yendidad,
original text, fol. Yendidad, with Pehlvi and Persian translations, fol.
Shah Namah, 2 vols. fol. Commentary on Shah Namah, 4to. Jog bishust,
translated from Sanscrit, 4to. Laksmi Narayan, translated from Sanscrit,
fol. Gulshan-i-raz, 4to. Commentary on Gulsban-i-raz, 8vo. Kiran-ul-
Sa dain. 8vo. Salukh (4), fol. & 8vo. Kbordab Avasta, with Persian
translation, 4to. The Divan of Afiz, 8vo. Lexicon to Desatir, 4to. Arabic
Syntax, 4to. Pehlvi Yocabulary, with Persian definitions, 8vo. Pehlvi
Yocabulary, fol. Avasta, original text with Pehlvi translation, fol.
Traditions of Zartusht, in Pehlvi, 4to. 1. History of the Peshdadyan;
2. Catechism in Zoroastrian Bitual ; 3. Pehlvi Yocabulary ; 4. Translation
of Khorda Avasta ; 5. Zend Yocabulary to No. 4. 4to. Letters by Harkaran,
4to. Letters by Mirza Mahomed Tahir, Minister to the Eing of Persia, 8vo.
Letters by Sadyaki, 8vo. Letters by Hasni, 8vo. Letters by Berehmun, fol.
Ethics, by Ali Shah of Bokhara, 4to. History of Eramarz, son of Rustam,
8vo. History of Ranjit Singh, fol. Biography of Zoroaster, by Behram,
4to. Rhetoric, by Khajah Ma'ruff, fol. Moral Precepts by Jamir, fol.
Morals by Husan ul Yaiz of Kashag’h, 4to. Arjun Bikhad, translation,
fol. Gulzari hal, 4to. Fables in imitation of the Gulistan, 8vo. Alle-
gorical Poem founded on the Kuran, 8vo. The Lover and the Beloved, an
Allegorical Poem, 8vo. Prayers and Praises to the Sun, &c., by Behram,
8vo. 1. Birds ; 2. Diwan of Uhmed, fol. Diwan of Saib, 8vo. Diwan of
Sanai, fol. Diwan of AYali. fol. The Mirror of Philosophy, fol. Collection
of Essays on Meditation, fol. The Treasury of Knowledge. On the Con-
nexion between the Soul and the Body, 4to. Mahomedanism and Zoro-
astrianism, an Essay, 8vo. A Discourse on the Zoroastrian Religion, 8vo.
1. Lunar Sect contrasted with the Zoroastrian ; 2. Dictates of Jamasp on
the Zoroastrian ritual, 4to. A Guide to the Study of the Kuran, 8vo.
The Religion of the Hindus compared with that of the Persians, 4to. On
the Unity of God and his Manifestations, 8vo. On the Knowledge of
God, fol. A Poem on Ali, 8vo. Kabalistic Philosophy, 8vo. Astronomy
(2), 4to. Alchemy and Astronomy, 4to. 1. Astrology; 2. Incantations,
believed to be cures for certain diseases, in the Zend languages, 4to.
On the Constellations, 4to. On Intercalation, 4to. Geography, 4to. On
Morals, 4to. On Ethics, 8vo. On Diseases and their treatment (3), 8vo
and fol. Letters, 8vo. History of Kings and Prophets of Persia, fol.
Doctrine of the Sheeahs, with Book of Martyrs, fol. Catechism, 4to. Moral
Tales, 4to. Science of Rhetoric, Prosody and Rhyme, fol. Poem by
Shiraz, fol. 1. On the Stars ; 2. A Fable of Mouse and Cat; 3. Laws of the
Stars ; 4. Essay on Meditation, fol. 1. Poems, translated from the Sanscrit ;
[ 23 ]
Presents.
MISCELLANEOUS ( continued ).
2. History of the Turks; 3. Salukh; 4. Memoir of Chundreban, fol.
1. Translation of Jawidan, from Pehlyi into Persian ; 2. A medical work ;
3. History of Astronomy, fol. 1. Prayers, poetical ; 2. Theological Ethics ;
3. Prayers, prose, 8vo. Arabic and Persian Dictionary, 4to. Pehlvi Dic-
tionary, with Persian definitions and Commentary, 4to. A Liturgical
Work, 8vo.
Also a Collection of Thirty-six Volumes of Persian Manuscripts on
paper, 8vo and fol., with titles untranslated. One MS. written on Palm
leaves.
Descriptive Diagram of a Seismometer invented by Lieut.-Colonel Eamstedt of
Helsingfors, and named by him Telegraph of the Accidental Movements of
the Earth. Stockholm.
Photograph of the Moon (40 in. x 31 in.), by Warren De la Rue, E.R.S. Framed
and glazed.
Photo-lithographic Impressions of Traces produced simultaneously by the self-
recording Magnetographs at Kew and Lisbon. 4to.
Portrait of Edward Somerset, Sixth Earl and Second Marquis of Worcester.
Proof engraving by W. Eaithorne. Framed and glazed. Funeral Certificate
of the Marquess of Worcester, copied from the Original in the Heralds’ Col-
ledge, with the Arms emblazoned. Framed and glazed.
MOHN (H.) Bewolkung in Christiania. 8vo.
Den Magnetiske Declination i Christiania udledet af Observationer
1842-1862. 8vo. 1863.
MOON (G. W.) The Dean’s English : a Criticism on the Dean of Canterbury’s
Essay on the Queen’s English. 8vo. London 1864.
MOORE (Sir Jonas) Contemplationes , Geometries, in two Treatises. 8vo.
London 1660.
MORGAN (S.) Horologiographia Optica. Dialing Universal! and perticuler.
4to. London 1652.
MUELLER (F., F.R.S.) Fragmenta Phytographise Australia. Vol. IV. 8vo.
Melbourne 1863—64.
The Plants indigenous to the Colony of Victoria.
Lithograms. 8vo. Melbourne 1864-65.
The Vegetation of the Chatham Islands. 8vo. Mel-
bourne 1864.
MURCHISON (Sir R. I., F.R.S.) Address at the Anniversary Meeting of the
Royal Geographical Society, 23rd May 1864. 8vo. London.
MYDORGE (C.) Examen du livre des Recreations Mathematiques et de ses
Problemes en Geometrie, Mechanique, Optique et Catoptrique. 8vo. Paris
1638.
NAMIAS (G.) Della Infezione Biliosa del Sangue (Colemia) Discorsi. 8vo.
Venezia 1863.
NEPAIR (J.) A Description of the admirable Table of Logarithmes, translated
by Edward Wright. 12mo. London 1618.
NEWTON (H. A.) On November Star Showers. 8vo. New Haven 1864.
Abstract of a Memoir on Shooting Stars. (Excerpt from
Amer. Joum. Sei.). 8vo. New Haven 1865.
Donors.
Burjorjee Sorabjee Ash-
burner, Esq.
The Author.
W. De la Rue, F.R.S.
The Kew Observatory.
H. Dircks, Esq.
The Author.
The Author.
H. Dircks, Esq.
The Author,
The Author.
H. Dircks, Esq.
The Author.
J. Robson, Esq.
The Author.
[ 24 ]
Presents.
ORESME (1ST.) Traictie de la premiere invention des Monnoies, textes fran-
cais et latin ; et Traite de la Monnoie de Copernic, texte latin et traduction
frangaise, publies et annotes par L. Wolowski. 8vo. Paris 1864.
ORMOND (Marquesse of)’s Proclamation concerning the Peace concluded with
the Irish Rehells. 4to. London 1649.
PAGE (T.) Report upon the System of "Weaving hy compressed Air in the
Pneumatic Loom. 4to. Cambridge 1864.
PAGLIARDINI (Tito) Essays on the Analogy of Languages. Second Essay :
The International Alphabet, or a Plea for Phonetic Spelling. 8vo. London
1864.
PANCIROLLUS (Guido) Rerum Memorabilium sive Deperditarum partes
prior et posterior, ab H. Salmuth. 4to. Francofurti 1631.
The History of many memorable things lost, which
were in use among the Ancients. 2 vols. in 1. 8vo. London 1715.
P APILLON (D . ) A Practicall Abstract of the Arts of Fortification and Assailing.
4to. London 1645.
PARLATORE (E.) Studi Organografici sui fiori e sui frutti delle Conifere. 4to.
Firenze 1864.
Intorno due Dissertazioni Botaniche di Michelangelo Pog-
gioli Considerazioni. 8vo. lloma 1864.
PARRY (C. C.) Physiographical Sketch of a portion of the Rocky Mountain
Range. 8vo. 1862.-
PERIGAL (H.) Revolution and Rotation. 8vo. London 1864.
PETTY (Sir W.) A Declaration concerning the newly invented Art of Double
Writing. 4to. London 1648.
PHIPSON (T. L.) The Use of Salt in Agriculture. Prize Essays. 8vo. Liver-
pool 1863.
The Utilization of Minute Life, being practical studies on
Insects, Crustacea, Mollusca, Worms, Polypes, Infusoria and Sponges. 8vo.
London 1864.
On Vanadium Ochre, and other sources of Yanadic Acid.
(Excerpt from Chem. Soc. Journ.) 8vo. London.
■ — ■ Le Preparateur-Photographe ou Traite de Chimie a l’usage
des Photographes. 12mo. Paris 1864.
Note on Vegetable Ivory. 8vo.
Description of a new Apparatus for producing Sulphuretted
Hydrogen. 8vo.
PICTET (F. J.) Note sur la succession des Mollusques Gasteropodes pendant
l’epoque cretacee dans la region des Alpes Suisses et du Jura. 8vo. Genbve
1864.
PLANTAMOUR (E.) Resume Meteorologique de l’Annee 1862-1863 pour
Geneve et le Grand St. Bernard. 8vo. Geneve 1863-64.
— et HIRSCH (A.) Determination Telegraphique de la
Difference de Longitude entre les Observatoires de Geneve et de Neuchatel.
4to. Geneve 1864.
PLAT (Sir H.) The Jewell House of Art and Nature, conteining divers rare
and profitable Inventions. 4to. London 1594. Another edition, 4to. London
1653.
Donors.
The Editor.
H. Dircks, Esq.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Author.
The Author.
The Authors.
H. Dircks, Esq.
[ 25 ]
Presents.
PLAT (Sir H.) The Garden of Eden, or a description of all Flowers and Fruits
now growing in England. 12mo. London 1675.
PLATEAU (J.) Sur un probleme curieux de Magnetisme. 4to. Bruxelles
1864.
PLAYFAIR (Lyon, E.R.S.) On the Food of Man in relation to his useful Work.
8vo. Edinburgh 1865.
POGGIOLI (Giuseppe) De Amplitudine Doctrinae Botanic* qua praestitit Fride-
ricus Caesius M. A. Poggioli in Archigymnasio Romano Doctoris decurialis
botaniees Commentatio. 8vo. Bomce 1865.
PONCELET (J. Y., For. Mem. R.S.) Applications d’Analyse et de Geometrie.
Tome II. 8vo. Paris 1864.
PORTA (J. B.) Natural Magick in twenty Books, fol. London 1658.
POUDRA ( — .) Histoire de la Perspective Ancienne et Modeme. 8vo. Paris
1864.
Des Reseaux. 8vo. Paris 1865.
— Memoire sur les Trigones, Tetragones, Hexagones. 8vo. Paris
1865.
Theorie Generale des Eaisceaux et des Involutions avec les
Applications aux traces des Courbes des differents ordres. 8vo. Paris
1865.
PURGOTTI (S.) Intomo alcuni scritti inediti di Michelangelo Poggioli, Nota.
8vo. Perugia 1864.
QUETELET (A., For. Mem. R.S.) Annales de l’Observatoire Royal de Brux-
elles. Tome XYI. 4to. Bruxelles 1864.
Annuaire de l’Observatoire Royal, 1864.
34e annee. 8vo. Bruxelles 1863.
Observations des Phenomenes Periodiques.
4to. Bruxelles.
Statisque et Astronomie. Sur le Cinquieme
Congres de Statistique tenu a Berlin Sept. 1863. Physique du Globe.
Phenomenes Periodiques. Notice sur la periodicite des Etoiles Filantes du
mois de Novembre. Sur les Etoiles Filantes et leurs lieux d’apparition.
Etoiles Filantes de la periode du 10 Aout 1863. (Excerpts from Bull.
Acad. Roy. de Brux.) 8vo. Bruxelles.
QUETELET (E.) Sur le Mouvement Propre de quelques Etoiles. (Excerpt
from Mem. Acad. Roy. Brux.) 4to. Bruxelles 1863.
RADAU (R.) Sur la Formule Barometrique. 8vo. Paris 1864.
Sur un Probleme d’Analyse propose par Lagrange. 8vo. Paris
RADCLIFFE (C. B.) Lectures on Epilepsy, Pain, Paralysis, and certain other
Disorders of the Nervous System. 8vo. London 1864.
RAMELLI (Agostino). Le Diverse et Artificiose Machine, fol. Parigi 1588.
RANKINE (W. J. M., F.R.S.) Papers on the Action of Waves upon a ship’s
keel, Isochronous-rolling ships, the Uneasy Rolling of Ships, and the
Computation of the probable Engine-power and Speed of proposed Ships. 4to.
London 1864.
RATHBORNE (A.) The Surveyor, in four Books, fol. London 1616.
MDCCCLXV. d
Donors.
H. Dircks, Esq.
The Author.
The Author.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Author.
The Observatory.
The Author.
Mons. d’Abbadie.
The Author, by Mons. d’Ab-
badie.
The Author.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
[ 26 ]
Presents.
EICEAFT (J.) A Survey of Englands Champions and Truths faithfull Patriots.
8vo. London 1647, rpr.
EINUCCINI (Gio. Batista) Arcivescovo diFermo. Nunziatura in Irlanda, negli
anni 1645 a 1649, publicata per cura di G. Aiazza. 8vo. Firenze 1844.
EOBINSON (J.) On the present position of the Agricultural Labourer. 8vo.
London 1864.
SAFFOED (T. H.) On the Eight Ascension of the Pole Star. 8vo. Camb. Mass.
1864.
SALTEE (J. W.) and BLANFOED (H. F.) Palaeontology of Mti in 'the
Northern Himalaya, being descriptions and figures of the Palaeozoic and
Secondary Fossils collected by Col. E. Strachey. 8vo. Calcutta 1865.
SAUNA SOLAEO (J. M.) Memoire sur le premier bassin de Dinotherium
decouvert dans le departement de la Haute-Garonne. 8vo. Toulouse
1864.
Nouvelle Theorie de la Grele. 8vo. Paris 1863.
SANTAEEM (Visconde de) Quadro Elementar das Eelagoes Politicas e Diplo-
maticas de Portugal com as diversas potencias do Mundo. Tomo IX. 8vo.
Lisboa 1864.
SAEGANT (W. L.) On certain Eesults and Defects of the Eeports of the Eegis-
trar General. 8vo. London 1864.
Inconsistencies of the English Census of 1861. (Excerpt
from Statistical Journal.) 8vo. London 1865.
SCACCHI (A.) Della Polisimmetria dei CristaUi. 4to. Napoli 1863.
SCHEEZEE (Dr. K.) Narrative of the Circumnavigation of the Globe by the
Austrian Frigate Novara in 1857-59. 3 vols. 8vo. London 1861.
SCHMIDT (A.) Hamatologische Studien. 8vo. Dorpat 1865.
SCHOLEFIELD (J.) Twenty-four Hours under the Commonwealth : a Drama.
8vo. London 1863.
SCHOLZ (B.) Anfangsgriinde der Physik, als Yorbereitung zum Studium der
Chemie. 8vo. Wien 1837.
SCHOPPEEUS (H.) n ai o7r\i« omnium iUiberalium Mechanicarum aut Seden-
tariarum Artium genera continens. 8vo. Francofurti 1568.
SCHOTTUS (G.) Magiae Universalis Naturae et Artis partes III. et IY. 4to.
Bambergce 1677.
SCHWENTEE (D.) Delicise Physico-Mathematicse oder mathemat. und philo-
sophische Erquickstunden. 3 vols. 4to. Nurnberg, 1636-92.
SEGUIN, Aine. Memoire sur l’Origine et la Propagation de la Force. 8vo. Paris
1857.
SELLON (E.) Annotations on the Sacred Writings of the Hindus. 8vo. London
1865.
SMITH (Dr. E., F.E.S.) Address to the Subsection of Physiology of the British
Association, Bath, Sept. 15, 1864. 8vo. London.
SMITH (James) The Question, Are there any Commensurable relations between
a Circle and other Geometrical Figures? answered. London 1860. Letter
to the President and Yice- Presidents of the British Association, Liverpool,
1862. A Hole in Smith’s Circle, by a Cantab. London 1859. (In 1 vol.)
SMITH (E. Angus, F.E.S.). Eeport on the Air of Mines and Confined Places,
fol. London 1864.
Donors.
H. Dircks, Esq.
The Author.
Harvard Observatory.
Colonel Strachey, F.E.S.
The Author.
The Lisbon Academy.
The Author.
The Eoyal Society, Naples.
The Author.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Author.
The Author.
H. Dircks, Esq.
The Author.
[ 27 ]
Presents.
SMYTH (Admiral, E.R.S.) Sidereal Chromatics, being a reprint, with additions,
from the “Bedford Cycle of Celestial Objects” and its “Hartwell Continu-
ation ” on the Colours of Multiple Stars. 8vo. London 1864.
SMYTH (C. P., F.R.S.) Astronomical Observations made at the Royal Obser-
vatory, Edinburgh. Yol. XII. 4to. Edinburgh 1863.
Report read by the Astronomer Royal for Scotland to
the Board of Visitors of the Royal Observatory, Edinburgh, 4th November
1864. 4to.
SORBIERE (S.) A Voyage to England, done into English, 8vo. London
1709.
SPRIGGE (J.) Anglia Rediviva, England’s Recovery, being the History of the
Army -under Sir Thomas Fairfax. fol. London 1647.
STAINTON (H. T.) The Natural History of the Tineina. Vol. IX. 8vo. Lon-
don 1865.
STEWECHIUS (G.) Veteres de Re Militari seriptores. 8vo. Lugd. Bat.
1592.
STURLEVANT (S.), ROVENZON (J.), and DUDLEY (Dud). On the Manu-
facture of Iron. 4to. London 1612-1665, rpr.
STURM (L. C.) Kurtzer Begriff der gesambten Mathesis, bestehend in V. Thei-
len. 8vo. Frankfurt an der Oder 1707.
SYMONS (G. J.) British Rainfall. On the Distribution of Rain over the
British Isles during 1860, 1861, 1862, 1863, 1864. 8vo. London 1862-65.
TARTAGLIA (N.) Opere. 4to. Venetia 1606.
TATNALL (R.) An Antidote against the sinfull palpitation of the Heart or
Eear of Death. 4to. London 1665.
TEYLER (J.) Architectura Militaris. 4to. 1553.
TODHUNTER (I., E.R.S.) A History of the Mathematical Theory of Proba-
bility from the time of Pascal to that of Laplace. 8vo. Cambridge 1865.
TOYNBEE (J., E.R.S.) Beneficence in Disease : being an Introducytoiy Address
delivered at the opening of St. Mary’s Hospital Medical School, October 1,
1864. 12mo. London 1865.
TREADWELL (D.) On the Construction of Hooped Cannon. 8vo. Boston 1864.
TRITHEMIUS (J.) Libri Polygraphiae VI. 8vo. Argentina} 1600.
TURNOR (H.) Astra Castra : Experiments and Adventures in the Atmosphere
[Prospectus]. 4to. London 1864.
TYMME (T.) A Dialogue Philosophical wherein Natures secret closet is opened.
4to. London 1612.
VEGETIUS RENATUS et alii Seriptores Antiqui de Re Militari. 8vo. Vesalice
1670.
VERNON (G. V.) On the direction of the Wind at Manchester during the years
1849-61. On the Number of Days on which Rain falls annually at London.
On the Rainfall at Oldham, by J. Heap. (Excerpts from the Lit. Phil. Soc.
Manchester Mem.) 8vo. London 1864.
— On Excess or Deficiency of Temperature. On the Temperature
of November. (Excerpts from the same.) 8vo. London 1865.
VICARS (J.) England’s Worthies, under whom all the Civill and bloody
Warres since anno 1642 to anno 1647 are related. 8vo. London 1647,
rpr. 1845.
Donors.
Admiral Smyth and Dr. Lee,
F.R.S.
The Observatory.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
The Author.
The Author.
The Author.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
[ 28 ]
Presents.
WAKE MANN (T.) Antiquarian Excursions in the Neighbourhood of Mon-
mouth. 8vo. Monmouth 1860.
WATTS’S (H.) Dictionary of Chemistry. Parts 17-26. 8vo. London 1864-65.
WESTALL (W.) Six Views of Raglan Castle, folio.
WHARTON (G.) Calendarium Carolinum, or a New Almanack after the old
fashion for 1662. 12mo. London.
WHEATLEY (H. B.) Notes on some English Heterographers. 8vo. London
1865.
WHICHCORD (J.) On Hydraulic Lifts. 4to. London 1864.
WIDDOWES (D.) Naturall Philosophy, or a Description of the World, namely,
of Angels, of Man, of the Heavens, of the Ayre, of the Earths, of the Water,
and of the Creatures in the whole World. 4to. London 1621.
Naturall Philosophy, the second edition. 4to. London 1631.
WILCOCKS (Alex.) Thoughts on the influence of Ether in the Solar System,
its relations to Zodiacal Light, Comets, the Seasons, and periodical Shooting
Stars. 4to. Philadelphia 1864.
WILLIAMS (J.) Some Account of a Japanese Chronological Work. 8vo. Lon-
don 1863.
On an Example of Chinese Paper Currency of the Ming
Dynasty. 8vo. London 1864.
WILLIAMSON (George) Observations on the Human Crania contained in the
Museum of the Army Medical Department, Port Pitt, Chatham. 8vo. Dublin
1857.
Military Surgery. 8vo. London 1863.
WILSON (Erasmus, E.R.S.) An Inquiry into the relative frequency, the dura-
tion, and cause of Diseases of the Skin. 8vo. London 1864.
WINCHELL (A.) On the Saliferous Rocks and Salt Springs of Michigan. 8vo.
1862.
— Descriptions of Eossils from the Marshall and Huron Groups
of Michigan. 8vo. 1862.
— • Salt Manufacture of the Saginaw Valley, Michigan. 8vo.
1862.
Description of Elephantine Molars in the Museum of the
University. 8vo. Ann Arbor 1863.
Eossils from the Potsdam of Wisconsin and Lake Superior.
8vo. 1863.
WINKLER (T. C.) Musee Teyler: Catalogue Systematique de la Collection
Pale'ontologique. Liv. II. 8vo. Harlem 1864-65.
WOLOWSKI (L.) Les Finances de la Russie. 8vo. Paris 1864.
La Question des Banques. 8vo. Paris 1864.
WORCESTER (Marquis of) A Century of the names and scantlings of such
Inventions as at present I can call to mind to have tried and perfected. 12mo.
London 1663.
A Century, &e., 1663, reprinted, 8vo. London.
— A Century, &c., 1663, reprinted, 12mo. London
1746.
Donors.
H. Dircks, Esq.
The Editor.
H. Dircks, Esq.
The Author.
The Author.
H. Dircks, Esq.
The Author.
The Author.
The Author.
The Author.
The Author.
The Author.
The Author.
H. Dircks, Esq.
A Century, &c. 12mo. Glasgow 1767.
A Century, &c. 12mo. London 1786.
[ 29 ]
Presents.
WOBCESTEE (Marquis of) The Century of Inventions, from the Original MS.,
with Historical and explanatory Notes by C. E. Partington. 8vo. London
1825. The six editions in a morocco case.
YATES (James, F.B.S.) Some Account of a Yolume containing portions of
Ptolemy’s Geography and of the “ Geographi Grseci Minores.” 8vo. London
1864.
YOUNGE’S (Walter) Diary from 1604 to 1628, edited by George Koberts. 4to.
London 1848.
ZEISING (H.) Theatrum Machinarum. 5 vols. in 1. 4to. Ldpziclc 1612-14.
ZEPHAEOVICH (Y. Bitter von) Krystallographische Studien iiber den
Idokras. 8vo. Wien 1864.
Donors.
H. Dircks, Esq.
The Author.
H. Dircks, Esq.
The Author.
MDCCCLXV.
e
Live Music
Archive
Librivox
Free Audio
Metropolitan Museum
Cleveland
Museum of Art
Internet
Arcade
Console Living Room
Open Library
American
Libraries
TV News
Understanding
9/11